Is Bi - amping worth the trouble?

Hello all...

I'm on the fence with the thought of bi amping. A big part of me wants to go ahead with it... the 'wallet' part says "Not so fast".

There should be lots of folks who've biamped speakers before... When it was all said and done, "Was it worth the time and expense?"

I'm inclinded to add a tube amp for the upper end of my VR4 JR's ... or any other speakers for that matter... though in any case and reardless the speakers, tube amp on top, and SS on the bottom.

...and then there's the thought of keeping two dissimilarly powered amps matched at the same volume level... and the added IC's, PC, and stand... it does seem to add up.

... and at this point, I'm thinking BAT to keep things all the same... and am not sure there, wether even that matters too much...

I sure do appreciate the input.
If you are going to bi-amp the VR4JR's, you will need the same amps on the top as you have on the bottom.
It has been a long time since I have bi amped but I have found that I like keeping it simple with the highest quality components I can afford. Currently I am using a pair of McCormack DNA-1 monoblocks with all of SMCs mods and enjoy them more than anything else I have had on the Essence 10A speakers. Hope this helps. From my expierence more is not always better. Will follow this thread to see what you decide.
Not with your system.

If you had an amp that wasn't up to the speakers, that would be a different story. Biamping is rarely as easy as plugging in another amp and wires. Unless you have another amp hidden in the closet or a friend willing to loan for a trial, there are too many variables.
With those speakers, as with most speakers in general, you will see a greater return for your money by going tube preamp instead of biamping with tube/ss. Everyone will eventually try to biamp and many will go back to single amp of high quality. The JR's would sound just fine with a good biamp configuration but the money spent on that upgrade would be better spent going to the SR version. Night and day difference between the two.

Good luck!
You do not need the same amp for top and bottom, you can have SS for the woofer and tube for the top or 2 ss amps that dont match, as long as atleast one has gain control that will allow you to match output to your taste, I am Bi-Amping my VMPS (wich is designed to be Bi-Amped, I also Bi-Amped my Innersound Eros (both use an outboard cross-over.
Although there is alot to be said about keeping it simple Bi-Amping allows you to get the sound you want in the Mid and treble regions that one amp may not provide, ofcourse one great killer amp will provide great results.
I use a high power Carver for the woofer and an Aragon for the mids and tweeters. I also like the gain on the bass amp because it gives you some bass adjustment for various recordings and moods.
Based on my experience with Linn equipment, which is meant to be upgraded by multi-amping, I would say that passive biamping is a small, but noticeable improvement. However, I question its cost effectiveness. On the other hand, active biamping is a huge upgrade. My opinion is that passive biamping is just an intermediary step, for budgetary reason, on the way to an active system. If a person was going to stop at the passive biamping point, I would say that you could probably get a bigger return for the investment by upgrading elsewhere.

Passive? Active? Mind clarifying the diffs from one to the other?

My VK5i preamp has two sets of active outs for amps... BAT probably figured on two same amps (bridged and/or unbridged) with gain controls for each ch./side... and that's it... oh, and a line out... all balanced. So same - same seems the least troublesome path... but I simply don't know. It's that darn tube sound that gets me to want to do this....

.. Sorry, man, I don't get what you're saying. I need to change my amp? ... and I was just getting to like it... or maybe you meant don't bi amp as the amp is fine... sorry, that statement was too open ended for me.
When you passively biamp, you continue to use the crossover network in the speaker. The signal comes out of the pre-amp and you feed two power amps. If power amp number one feeds the tweeter and woofer of speaker number one, and power amp number two feeds the tweeter and woofer of speaker number two, it is called vertical biamping. On the other hand, If power amp number one feeds the tweeters of both speaker number one and speaker number two, and power amp number two feeds the woofers of both speaker number one and speaker number two, it is called horizontal biamping. In both cases, however, it is "passive" because you continue to use the crossover in the speaker.

Because of inefficiencies in speaker crossovers, another type of biamping is "active" biamping. With this, the signal comes out of the preamp into an electronic crossover, which separates frequencies into high and low frequencies. The high frequencies then go to power amp number one and then to the tweeter terminals of both speakers. The low frequencies go from the electronic crossover to power amp number two and then to the woofer terminals of both speakers. Since the separation of the signal into high and low frequencies has already occurred, you do not need the speaker crossover to do the job, so it must be disconnected.

With a precise separation of the signal by the electronic crossover (which does not occur with a speaker crossover), active biamping eliminates a whole bunch of various distortions which can otherwise occur. It also increases your apparent amplifier power, which helps with dynamics, because passive speaker crossovers suck up about 90% of your signal.

In active biamping, not only do you need to buy another amp, but you need to buy the electronic crossover, so it is a bit more expensive to implement. In addition, you need to perform surgery on your speaker by disconnecting the crossover.

It is extremely important to note that going active presumes that the speaker can be modified in this fashion. Many speaker designers don't envision their speaker crossovers being eliminated for active operation, so they are not desgined to be modified in this fashion. It then becomes a crap shoot as to whether it will be an improvement or not. Unless you know for sure that your speakers are meant to be upgraded in this fashion, you probably should not even attempt to go active.
Curious why you need to use the same amps for the 4jr's ?
I've stayed away from biamping with different types of amps because of coherency issues. Even with steep slope crossovers you have some mixing of dissimilar amplifier characteristics.
"Curious why you need to use the same amps for the 4jr's ?"

Many amps from different manufacturers have different gain which will affect loudness of one driver in relation to another, eg. you could end up with a really loud tweeter!
Jtinn and Brrgrr, you do not need to use the same amps top and bottom. Many people mix and match when biamping horizontally precisely because they want each amps' distinctive characteristics, tubes on top and solid state on the bottom for example. The amps do need to have the same gain however. If they don't, then whatever is connected to the higher gain amp will sound louder for a given volume setting. So you could have woofers that sound louder than tweeters, or vice versa. It would be like having a vetical balance control within a speaker. If the amps don't have the same gain, some will have an internal setting for gain adjustment. Others would require a technician to adjust one to match the other.
Keep in mind when you bi-amp the Vr-4 Jr's you will still be using all the componants of the crossover just seprated. There for there will NOT be a gaint gain diffrence.
The important part is will you be able to detect where the low end leaves off and the mids/highs start.Also level matching and you will never be 100% sure if the correct levels are right. Put the money in a great single amp and bi-wire. I have Large von schweikerts and biamping wasnt the end all.
Okay. Your amp is fine.

Doctor Mark's reply, though considerate and correct, is just the tip of the iceberg. Feel free to experiment, learn and have fun.
An interesting thing to try is to get the panasonic Sa-xr57 digital receiver. Which is a 100 watts x 7 and has a biamp function built into the unit. When biamped in stereo mode, it uses 4 of its internal amps for the bass section and one each to the highs. So it uses 6 of its internal amps when in biamp mode. All you have to do is run your speaker wire and push the biwire function and you are good to go for 300 bucks. It also has a great sound and has suprisingly great bass tone and slam and never gets hot.
You can also increase or lower the gain to the bass or treble, independant of tone controls if one seems hot to you. I know it is not expensive and no tubes are glowing, but you might find it interesting.
... got it. Thank you.

Got it. As I was listening to the input you posted it started coming back to me... the vertical thing was the way I initially thought to go... with the same VK500 w/BP amps. Possibly bridged... though not at first. then I thought better of that deal and figured on the tube + SS. Given the refresher/reminder course you were so kind to post, I see a bit more clearly that 'dream' could well become the 'nightmare'... and pricey. Thanks for the reality check. Another thing VK had told me about was the 'gain' issues. Even two 500's wouldn't be entirely matched exactly... and it was very doubtful that BAT could match them perfectly.

Well, gee. that's a drag. Oh, well... it was a nice dream while it lasted. I'm still dead set on trying tubed amps though.

'preciate the input on using the Sony rec., I've already got one, yet never thought to use it that way... mine puts out a bit more power than the suggested one, but i'm too disappointed now to give it a shot.

Bi amping given the info posted here, at least for me, seems way more involved than I had thought. But being an audionut, I thought the "bi-amping path" to really be the 'end all be all' in audio.

I more than appreciate the efforts, knowledge and experiences you have provided me. Thank you very much.
I'm using a hybrid on top and a SS amp on the bottom of my Vmps Rm 40's. Many people will tell you that at least with planar/electrostats that some tube magic on top can be magic. They were right!

I think the main advantage is to take the best qualities of two amps and use them there as I have. Another benefit however is reducing the amount of crossover components you're using. In the end experiementation is key. With our VS's I don't know as I've not heard them. You could also try various tube preamps. Please remember different tube preamps will sound widely different. Some not very euphonic like Audio Research to somewhat more, Conrad Johnson, to syrupy.

Biamping in my experience in my system has been the best way to go. If you haven't owned any tube gear it's a must try. A hybrid amp like the Van Alstine Fetvalves are excellent. The Blue Circle I had also was an outstanding amp, although quite expensive for the money. On the bass using this Rotel 991 is excellent. The bass quality is outstanding and I'm picky in that department. For under 500 bucks there's a few amps that will work well for the bass.

Best of luck and have fun!
Mark has given a great

My system was passively bi-amped for a few years. At first I used a pair of SS amps, one on each speaker. Then, just like Blindjim, I wanted to add tube amps to the mix since I was enjoying having a tubed preamp. So, I sold off one SS amp and then added a pair of tubed mono-blocks that drove the mid and high freq. and let the SS handle the woofers on both. A horizontal configuration. The gains where within 1 dB, not perfect but a pretty good match. Now I was getting closer to what I wanted to hear, but there was still something missing. I could not put my finger on exactly what it was. Music sounded better, but still there was some lack of even delivery across the spectrum.

I kept listen and also kept researching. It finally occured to me that what I was really trying to do was compensate for the short-comings of the cross-over circuitry and in-efficiency of the speakers. I have sinced moved to a single, high quality single amp and a much more efficient 2-way speaker. The dynamics, clarity, speed, timbre, pretty much everything is much, much better. I can play the sweetest chamber music or the hardest rock or the fastest jazz and hear so much more musically.

Our listening preferences and system goals may be quite different, but I offer my experiences since it sounds like you may be looking for what I was looking for. Hopefully, you can find something useful in what I've written hear.

Best of luck in your search,

Blindjim, Do not let it go so fast, Biamping does work and to very good extent. I really like tube mids.
Just use the Xover in your speakers, they were designed with them and you should keep them, just add a tubed amp in the mids and highs, and an SS on the bottom, use a passive preamp like the EVS attenuators or the Luminous Audio preamp on the bass amp and let the tubed amp run free. The speaker xover will allow your speakers to do their job properly. You will win much more definition and dynamics on both bass and mids, you will get the "tubed" sound on the mids.

Since the power needed for mids and highs is much less you can do with a simpler push pull amp with a coule of power tubes per side, these have better definition to my ears that huge monster tube amps with 6 or 8 tubes per side, wich is what you will need if you decide to go tubes without biamping (these are much more expensive also!)
So finally from the preamp add a "Y" connector to the tube amp on one side and to the mids and highs; on the other connector to the passive preamp and the bass SS amp, that way you can adjust the volume needed on the bass amp.

Once you get the hang of it you can add a passive line level Xover (PLLXO) on the tube amp to avoid getting low freq. into it (say from 100hz up) that will help the amps a lot, more definiftion and dinamics again.

If you like symphonic music this is the best way to go!
If you are into girl with guitar music you dont really need biamping.

I am not biamping right now since my new speakers wont let me, and I miss it, I am thinking on adding a pair of subwoofers and a PLLXO on my tube amps....

Do try it!
It seems to me that an Electronic Crossover is the way to go. I remember years back I had 4 Carver M500 Amps that I used a Furnam Electronic crossover. It was a Pro type with 1/4 " phone plugs. With adapters I was able to make it work quite well. It had variable croosover, db slopes adjustments and Main and single level controls. I sold it and all the Carver Amps, when I thought I needed "better quality Equipment". (Still searching after all these years)
After reading this thread, I want to ask,
Is there any type of Audiophile Electronic Cross over today?
Good question. Hope there is an answer forthcoming.
This is a pretty famous Active Xover I guess High End though I never used it myself:

This is Passive option:

All the Best
Sorry PLLXO:
That speaker is not that large, and may not need tons of current for very satisfying listening levels.. The advantage of bi-amp is too balance out a top heavy speaker for the most part, loaning an entire channel to take on the bass drivers to relieve that saturation to the highs and mids.. It will be very dependent on the amps, and speakers reaction to it whether it will be worth it.

Honestly its tuff to find Biamping always better, but in some situation it could sound better. It would not probably hurt at all if using 4 exact same channels, however might not have enough advance for you to keep the investment into it. However definatley ACTIVE bi-amping, which will be at least removing your passive Crossovers from the Woofer section can be a whole different thing, and yes if you active the whole speaker you can juice more out of the finer points of discrete channels.

However again the cost and the needed equipment, Tuning, and Time can outweigh the the "Is it worth it factor". Try it first with 2 identicle amps simply hooked thru the passive crossovers. see if you wish to proceed, its the only way, you have to hear the investment or forget it.


Sage advice. Thanks.
I have been thinking about the same thing as I own VSA-4JRs and have run them with 200W SS and 80W tube amp. There are compromises with each of these. It is interesting that a couple of well respected speaker designs are essentially bi-amped, the Vandy 5A and Von Schweikert 99DB. I think that it could be worth it on the 4JRs.
Maineiac, your confusing something, those are Active Sub systems in the DB99.. Not really a biamp, its basically a seperate electronic crossed over system. Yes Active bi-amping can be effective like the db99, however we are talking about a passive standard 3 way type crossover with 2 amps hooked up. Different application in the end.
Blindjim- Your interest in bi-amping seems to be driven by boredom or curiosity more than need. And, while bi-amping might be an available option, your speakers were not designed with that in mind. I believe that the Vandy and VS speakers mentioned above have proprieary inboard amplification designed specifically for the woofers they are driving. In your application, the matching would be by chance.
If you are unhappy with what your speakers provide, consider replacing them with something more satisfying. If you like what you have, then consider hiring Rives to upgrade your listening environment or buy a Magic Clock.
Otherwise just sit back and enjoy. If it ain't broke, don't fix it.
I feel like the little devil on Blindjim´s shoulder....
Do biamplify It is great you wont regret it!!!
It is really not that difficult, I would not change the speakers a bit, leave alone the speakers Xover just get the amps to run better, active or passive line level Xover is good...
This is a hobbie right? We do crazy things to achieve better sound..So get your hands dirty and work on it!!
Trust me it is great!

Electronics isn't magic and fairy dust. It's learning and experience. If something is made for a dollar, it can be made better for two dollars. Either that, or you can completely screw it up and call it a learning experience.
Blindjim: Unless you're technically inclined with test equipment, stick to using identical amps that have been gain matched at the factory. Otherwise, it is easy to run into some strange situations that seem to vary from recording to recording.

Other than that, passively bi-amping is worth a small gain in terms of dynamic range and slightly smoothing things out. Unless one is using an under-powered amp for the specific speakers / desired listening levels, the associated costs aren't really worth the efforts in my opinion. Like you said, the extra amp, interconnects, speaker cabling, etc... can really add up quickly. If running big amps, another dedicated line might also have to be factored in.

When all is said and done, the money that you spent bi-amping could have probably been put to better use by either upgrading the speakers and / or amp. Adding a quantity of gear won't necessarily get you the quality of signal that you desire. Sean
I have passively biamped various speakers, with stunning results. I call it dual-amp biwiring, not "biamping", because traditionally biamping has ALWAYS meant an external active crossover. I have tried two identical McCormack amps and also two identical Music Reference amps. I would NOT mix different kinds of amps. One stereo amp devoted to the left channel, and one for the right is my favorite way to go. For speakers, I have compared 2-channels vs. 4-channels on Magnepan, Musical Fidelity, and Signet. Each of these speakers is set-up for bi-wiring, with two pair of inputs per speaker. In every case, the fine dynamics and liveliness of the music has increased significantly. In every other way, I hear no significant difference in sound, but increased liveliness is EXACTLY what differentiates a great system from a good one.
thank you, you’ve been most helpful with your input and experience both here and elsewhere with my queries. Really, though, is bi-amping ever truly a 'need'? for that matter little of what we do with Hi Fi gear is ever a ‘need’ I suspect. Personally, I think it simple ‘ego’.

"Blindjim- Your interest in bi-amping seems to be driven by boredom or curiosity more than need." above. But you are probably right.

"And, while bi-amping might be an available option, your speakers were not designed with that in mind."

... I beg to differ, the designer did say differently, and if optimum performance were to be achieved. As did at least one reviewer, who tried several combinations during his account of the JRs. Given the former's, more so than the latter's input, and the curiosity/.desire you hit upon, here we are.... for regardless their accounts, one personal, one public, I’ve thought for some time now, to have a system with two amps… and I sort of do now, yet not in the classical sense, as my amp (s) share a single chassis.

I'm fast approaching the culmination of this exercise. three or four grand more and I should be near complete. Awaiting only a DAC to integrate my carosel (s) & PC.

Thus I'm pondering with some Enthusiasm, the notion of bi amping... so as to eek out that last bit or simply for the experience... I've never had a tube/tube set up. As the best sound I've yet to hear came from an ALL tubes rig, on the JRs, in fact, I'd like very much to attain that presentation to the degree I can afford. Ultimately. Though afforability looms large in this venture, narrowing the paths, and casting a brighter light upon the intricacies of each avenue seems only prudent to me. I'm sort of a belt and suspenders type. Measure two or three times, cut once. Knowing in advance and settting down the plan provides direction, and sets goals. Remaining flexible along the way is a must too. ...but that's me. That's just what I do. Research, therefore, is quite important when doing a new thing.

Thus whatever input I can obtain, from other's experience is of great import though not solely to myself, given these threads that increase all who are 'curious'. It's curiosity, remember, that drove us to folow our dreams and schemes down the Hi Fi Highway. …and that’s one thoroughfare whose toll can weigh quite heavily if it is errantly pursued.

Which brings me to this.. a dealer once told me that bridging amps reduces headroom… and the deficits outweigh the advantages… were I to gain another vk500 and just go that way, though I know it not a prerequisite, would bridging both amps actually be a poor choice, given it a vertical biamping set up? (that’s one amp per speaker, right?) . ?? AND “What’s headroom, exactly?” AND “What’s headroom, exactly?”
"Headroom" usually relates to the extra energy the amp has available to deal with (loud) transients in music without clipping.
Back to biamping --
a) I wouldn't have much to add to Sean's post above.
b) A quick reference of what you may expect with "passive" biamping is given by warjarret above. The result doesn't justify the cost -- esp. when compared to normal biamping (i.e. amp directly driving the drive units). That's a different level altogether.
...Unless you have a notoriously underpowered amp -- which you don't.

If V Scheik really means what he says about these spkrs having been designed for bi-amping, then he can provide you with the cross-over schematic, and you can take it from there.
Many thanks. ...well that's what he said to me on the phone, when we first spoke of the JRs set up. In fact he said the best two amp set up he had heard on them was with a vk60 & a vk solid state driving the lower unit. he did seem sincere enough that I believed him.

Having heard several medium eff speakers, (84 - 88db), I've haerd them with 200wpc - 600wpc... different spkrs, & different amps... the bigger the amps current supply, the better the sound. Everytime. IN both dynamics, and control. the quality however did not necessaryily improve. hence the desire to add a tube amp in conjunction with mine.
You're welcome. I'm happy to hear that you find me helpful.
Passive bi-amplification amounts to sending the signal from two amplifiers into the speaker's passive crossover and, unless lack of power is an issue, does not differ substantially from bi-wiring.
True bi-amplification places an active crossover between the preamp and the power amps, sending the portion of the signal that you assign to each amplifier and subsequently to each driver (or driver set). An active crossover will normally afford much more flexibility by allowing you to alter and adjust X/O points (frequency cutoff), crossover slopes (db/octave) and increasing or decreasing relative gain.
It also does not usurp a large portion of your amplifier power as the passive crossover in your speaker will.
I am not very familiar with VS design but I'm sure I've owned something like them in the past. Unless they provide you with a way to completely bypass their internal crossover, they are not setup for true bi-amplification and the advantages it affords. Please remember that much of the advice you receive from dealers, the factory and even certain, if not all, reviewers is driven by marketing interest. This forum is a good, neutral source of info but you need to be aware that at least some of what you read here is the well-intentioned echo of the aforementioned marketing people.
With 84 - 88 dB speakers, you could never have enough power. This is why you've heard very noticeable improvements when providing them with drastically increased amounts of reserve.

Other than that, i would consider 84 - 88 dB speakers to be low efficiency, not medium. Of course, i'm talking about using 1 watt @ 1 meter and not 2.83 volts @ 1 meter standard of measurement. There can be HUGE variances in rated output using the latter format depending on the nominal impedances of the speakers being compared. Using 1 watt provides a FAR more uniform standard of measurement. Sean
As a cost saving measure, remember that when you bi-amp, you need amplifiers of far less power to achieve the same loudness and headroom. With Magneplanars, I was unhappy with a 35 wpc tube stereo amp, but fine with two of these, passively bi-amped (AKA dual-amp bi-wired). So, I could concentrate on fine quality amps, but not necessarily high-power fine quality amps.
Oh, I have a couple more comments: don't bridge! Bridging an amp compromises its technical performance, and I have heard the degradation. If you decide to use one stereo amp per speaker, bi-wiring the two channels separately with a Y-connector up-stream (AKA passive bi-amping) is MUCH better than bridging. To say that "its not worth it" is not in the spirit of high-end audio. We all know that more fussing and more money brings about only incremental benefits. So, if a difference is definately audible, then the reward is achieved.
I dont really see the point of biamping if you are using the same amps, I have done it and the difference was really minor, go tube for the upper range.

Yes the best Ultimate way to Biamp is to open up your speakers and pull the XOver out and wire each driver directly, remember you then have to use 3 amps, one for each driver that is woofer, mids and tweeter, wait you have two woofers there make that 4 amps! While your at it change the wire going into each driver and by the way add some blue tack to the frames of the drivers. Leave the wire long enough so you can hard wire directly to the amps terminals. Do use silver wire for mids-tweeter and copper for both woofers. You can also use different interconnects from the active XO to each amp, I would recommend Nordost for mids and tweeter amps and Siltech for the bass amps.

Of course you can start slowly and enjoy each step of the way! No other system will sound better to you.

I would start the easiest and cheapest way possible, see if I like the changes and do some more. Say get a nice tube amp, there is a new Genesis amp push-pull with 6550 tubes that I think would sound wonderful, it was designed with biamping in mind, or say a McIntosh 275 or 240 amps. and just "dual-amp biwire" it, If you like this for the amount of 2 bucks you can make a passive line level XO, which is what most gung-ho biampers recommend (check the Oris speaker website) some say first order is the best (Romy the cat). Before buying an Active Xover I would probably change the values on the tube amp coupling capacitor and resistor to avoid low freq. this would be the most purist way to do it (I have done it) you also avoid another set of ICs which is not only expensive but detrimental to sound (not to mention the damage an active Xover will bring to the system) Now for the tweeter amp the line level Xover didn’t really worked all the way up, the best thing there would be to add a cap between the tweeter and the amp (Hovland?). I would use the active Xover for the bass amps, there is where the passive original Xover does the most damage! Those huge caps and huge inductors are no good!

Be brave and do it!
If you can run Solid state on the bottom with LEVEL controls, which many do not unless running a pro audio amp than you will have difficulty matching up gain with a tube amp on top.. YES there are still benefits of running 2 of the same amps in a verticle bi-amp config, this is because you will still have dedicated Current running to just the bass drivers not sharing it with the upper end. However it can be as explained here to some more accurate degree very little advance, unless it is just the right amp speaker combo it could be substantial even in a passive crossover system. The VK 500 you have in question is a Dual mono with dedicated power supplys to each channel I believe, so Having 4 Dedicated transformers, with Hi current and Higher Capacitance per channel can be better even with the same 2 amps... Also, I totally agree that DO NOT bridge and expect better results, the Verticle bi-amping with 4 channels should prove to sound better anyway, but you could experiment both ways if you have the amps that can bridge in the first place.
Sweet jumpin' jellyfish! ...and all I thought I was going to need was another amp and a couple wires! Oh. My. God... or Gosh! for the more reserved among us.

I mean, really. that's a bunch. Can't just come out of the preamp to the X over and then to the amps and use the X over in the speakers, huh? Super. Just super. More than two amps just ain't happening sportsfans. Nope! Sorry. I'd not trust myself these days to do any fine electronical work. that's over with... I have the know how. I have the technology. but I can't rebuild the six million dollar man, eh, speaker.

If removing X overs in the speakers, is a 'MUST DO' with either method, passive, or active, I'd need farm that out.... and if THAT entailed more amps... well, see previous paragraph.

..and we're back to the "Is it worth the trouble?", thingy, once more. Sure sounds like a lot of trouble to me. Unless I can add another pair of ICs... another amp... maybe make a move in changing out my speaker cables... then I'll have to cry "Uncle!"... it's just beyond me... I'd even go so far as to add another device like an outboard X over... the consequential wires it would dictate, but then you all said that would mean gutting the present X overs in the speakers... and doing each driver in and of itself... Whoa Nelly! Sorry kids. That dog won't hunt. Unless!? well, there's that redneck retirement we got down here each week.... maybe then.

What an 'eye opener'. For real. Guess times and technology have changed greatly. I remember this aspiration as being far simpler. To wit, my aforementioned, and succintly now debunked plan. Well if two amps do wind up somehow driving my speakers, then super! If not, getting a tube abp will happen. Till then, I'm disappointed. yet in all glad to know the truth of things up front. The purist approach is out almost entirely. Gone. We'll see just how slam bang a tube amp I can come up with first... then refer to these notes one more time.
Now, you're beginning to get it.

So back to your origional question: Is it worth it?

I had a pair of power pigs and an old 100 wpc amp. It was a very strong 100 watts though but I auditioned another pair of monoblocks that were much more refined and had great imaging. Unfortunately the monoblocks didn't have nearly the bass depth and slam. No problem, just use all the amps, right?

The good part was that the bass crossover was at 90 Hz. If it was any higher, it would be more difficult because the hearing is more sensitive in the midbass.

Still, not that simple. First, the old amp was inverting. Easy fix; reverse speaker wires to bass. Then the gains didn't match so I went down to the doohicky shop and bought a 5 KOhm carbon potentiometer, a box and some female RCA's. Wired that up and twiddled for weeks. It was better but not quite right. Every time I changed the volume, I had to adjust the gain. Every CD had to dialed in. Even then, it always seemed bloated around the crossover point. Went back for a different doohicky. This time, it was a wire-wound pot. No better. Another thing that happens with multiple amps is ground loops and hum. Just another part of the learning experience.

Started looking at active crossovers and what would be involved. They ain't cheap. While I knew the crossover point, I could not find the slope of the passives in the speaker. Considering that each order (1st, 2nd...) adds 90 degrees of phase and and the speakers were designed to be coherent at one of those, I thought I should know. Turns out that wasn't relevant because active X-overs have a choice between 24dB/octave and 48(8th order). I also started to learn something about notch filters that I could not account for. In the speaker, the x-over was soldered on a circuit board. This seemed like brain surgery at the time and I could have ended up with a pile of parts. Now, with a bit more knowledge, these aren't simple problems but nothing insurmountable.

There was one other alternative, or so I thought. I bought a dual, 23 position rotary switch (attenuator) and a bag of resistors. This ain't cheap either and it certainly wasn't easy but Mr. Doohicky was happy.. Soldering 46 tiny resitors on a tiny switch is not fun. The ones that can be bought preassembled had a higher range than I needed. I chose all the resistors between 1K and 3K and added a DPDT switch that added another 3K (paralleled 6K), 6K or nada. Much better. No more fiddling with it, at least not after the first month, and no bloating. It also gave a great way to adjust the bass to my tastes. The DPDT switch turned out to be unnecessary.

Granted, an active would have killed that passive parasite and made the speaker much more efficient, I still have to wonder. I was planning on building a set of speakers from the ground up with an active x-over, because I'm convinced that's the best, but a sweet deal popped up.

The next set of speakers had an active x-over/bass amp from the factory. Well, semi-active, but let's not go there. It has controls for gain, low-pass, hi-pass and phase. Hooked it up with those little monoblocks because I didn't exxpect the midbass and up to take much power. Lots of trial and error with the settings and location. Changed from RCA to XLR. Different preamps, even built one myself. Learned that phase is more than quarter turns (90 degrees) and could hear within 10 to 15 degrees on either side and went for the middle.

No matter what I did, there was a dip at the crossover until a friend brought over his behemoth SS amp and the dip went away. I also tried with tube amps but not my taste. You could say the little monoblocks was a mismatch of character. The 1600 watt bass amp had a lot more. I was expecting to buy a new amp for the speakers but not quite so soon. Now, I've got three behemoths and it all worked out beautifully. By the way, bridging does work for some amps.

If you want to know see how complex it can be to make a versatile x-over, check out Wisdom's "Brain".

Did you expect a short story?
I am sorry Blindjim to scare you like this, but this is what it means when somebody talks about using an active Xover to change slopes or Xover points, and bipassing the speakers XOver.

Like I said on my first post:
Just use the Xover in your speakers, they were designed with them and you should keep them, just add a tubed amp in the mids and highs, and an SS on the bottom, use a passive preamp like the EVS attenuators or the Luminous Audio preamp on the bass amp and let the tubed amp run free. The speaker xover will allow your speakers to do their job properly.

I recommended a passive attenuator to match the gain on both amps, it is always best to "loose" some definition on the bass than on the mids, that is why the volume should be adjusted on the SS amp. To add an active stage (active XO) just for this would take away from the signal, because of this Marchand Electronics made a Bass Correction EQ :
Which is like an Active Xover for bass only, adding some other niceties... and leaving the mid and high source as pure as possible.

"I can add another pair of ICs... another amp... maybe make a move in changing out my speaker cables"

That is all it takes!

"I'd even go so far as to add another device like an outboard X over"

This would be good also, I would use the bass correction thingy for "bass" and a passive line level XO for the only other amp: the tube amp.

If you love this too much, in a couple of years you will be gutting your speakers to tear away the original Xover and hard wire....and maybe not, I wouldnt do it....I would get horns for that!!!

All the Best!
What Jsadurni says seems to make sense to me with the 4JRS since the mid-high box and the bass box are independent. If you can adjust for gain differences you should be able to bring the drive of SS to the bass and the strengths of tubes to the mid-high. I guess I was thinking that the DB99 essentially did this with an independently amplified woofer (I am guessing it is crossed over on its own).

This is what the 4JR manual says:
BI-AMPING THE VR-4 SERIES: If the tightest bass is desired, use a solid state amplifier on the woofer modules. If you value “image float” and liquid-sounding midrange/treble response, use a tube amplifier on the M/T’s. You will not need an outboard crossover, since the crossovers in the speakers will still continue to work. Although it is true that louder output can be obtained by high-pass filtering the tube amp, the loss of transparency is usually not worth it, and the clean volume obtainable without a high-pass crossover will be usually satisfying for anyone but a metal head.

“Did you expect a short story?”

uh, well, yeah, I did. At the onset. Not now, however.
Man! That’s a lot of doing… we can nix the soldering business right off.. I’m a plug and play sort these days… though not by choice. Thanks much.

“I am sorry Blindjim to scare you like this, but this is what it means when somebody talks about using an active Xover to change slopes or Xover points, and bipassing the speakers XOver.”

…it will take a mite more than this info to scare me off… far more, for I’ve faced far worse.

“use a passive preamp like the EVS attenuators or the Luminous Audio preamp on the bass amp and let the tubed amp run free. The speaker xover will allow your speakers to do their job properly.”

…. So simply attenuate the bottom amp with one of these items? So come out of the preamp to “IT” AND then to the amp? OK… a gizmo and two more sets of ics…. Yikes! Though that’s the cheapest path thus far … I think.

“If you love this too much, in a couple of years you will be gutting your speakers to tear away the original Xover and hard wire....and maybe not, I wouldnt do it....I would get horns for that!!!”

…not bloody likely. Were I to survive this endeavor, you can stick a fork in me. . .. I’m done. Well save the tube rolling, isoing, and PCing…. And extra riders on the home owners.

I just got off the phone w/BAT. Had a short little chat with VK. He uses a lot of words like perhaps, maybe, it’s possible, and so forth…. Yet he is inclined to think my now ‘semi’ debunked (there’s been a spurious post mortem resurrection, albeit short lived or no), plan should either be a safe & secure one that remains bright and shiny still, or ‘perhaps’ not. Still in all, he did say just what you did apart from the passive X over makers name…. he seemed to think or indicated that an ‘inline’ (one for each outgoing IC to the SS amp), was available. Plug & play! But no idea of who made them… but thereby just pluggin into the preamp, and moving the dial… IF things weren’t homogenous. He also cast his vote for the VK 75/75SE, along the way. Naturally. I am inclined to go with BAT up top… or a VAC, or…, we’ll see., but at least 60wpc or above.

He also indicated some degree of flexibility with the use of the various speaker taps on the amp as some accommodation… but did say it would affect more than the ‘matching’ aspect, and affect the sonics to some degree.

Any hesitation I uttered was only due to expense. Not involvement. Given things always work out just the way they are supposed to…. One way or the other… I still remain 100% undaunted (almost). You might even say “I am entrenched with my upcoming effort to bi-amp”. I wouldn’t but you might.

Is there such a thing as an inline attenuator like what VK said? If so, are they worth having?

I remain deeply grateful for any and all input/experiences provided me and others herein…. Really.
Many thanks.
Blindjim, you want a plug and play? Cheapest possible? Here you go, simply run your BAT on the Mid / High section.. Remove the jumpers of course on the speakers, and By a CROWN K series digital Pro power amp, it has about 1k watts per channel so you will have no problem with bass slam and transparency, and they can be found cheap on ebay and things(around 600 plus used).. Also it is digital so it runs dead quiet, No heat, tons of power for Live concerts because that is what they are used for, many people use these for subwoofer setups in real hiend theaters and 2 channel.

Now it also has Level knobs built right into it so you can adjust the gain on the amp to match up to the bass output you want without effecting the output of the Bat or anything at all for that matter.. However you will need to run a balanced cable cause they only have XLR and maybe 1/4" connectors on them. It is possible however unless your preamp has 4 volt output which it could very well be if using balanced XLR outputs on it, than you might not get full gain output of a PRO amplifier, cause most consumer products could be only 2 volt output which is half and I believe the crown will be looking for a 4 volt signal for 100% gain from it.

This is as plug and play as it gets, you just need another outlet open on the wall to plug the new amp in, and another pair of balanced cheap XLR cables, and another pair of copper 10 gauge lamp cord speaker cables... It will be damn powerfull that much is guaranteed.
Undertow -- that's actually a very good plan! Go for it, Blindjim...
We need to pull this thread together into a general concensus, because I think we all agree true-biamping is the best. Have I got this right? Short of tri-amping, the best way to biamp is to remove the bass and midrange crossovers in the speaker, dedicate the best bass amp to the low frequencies, the best mids/highs amp to the upper frequencies. Then you need to buy an active crossover with independant frequency and level adjustments, between the preamp and amps. For someone who doesn't want to spend this kind of money, nor the listening time to compare various amps, the question still remains about just how noticable bi-wiring is with two identical stereo amps. Someone called this passive bi-amping. Then you just buy another amp, just like the one you already own, plus a y-connector and duplicate pairs of short speaker and long interconnect cables. Each stereo amp can sit right next to each speaker (just the LOOK of this is worth something). No volume settings nor optimizing of amps will be necessary. I have heard the benefits of running separate speaker cables to the highs and lows, even though any electrical engineer will tell me it only my imagination. And, I can hear EVEN MORE of the same benefits, when I run different amps in the same type of bi-wire configuration. Try it... it sounds more lively, more dynamic, more detailed. Maybe its the reduced intermodulation distortion, maybe its musical karma. I don't care, it works. My technical friend tells me that whether the crossover is before the amp or after, either way it still eliminates the current at those frequencies through the amp. The amps and the wires have less frequency bandwith to contend with.