Biamplification in Mid-Fi?


I'm looking at upgrading my home system. It's likely going to end up being mid-fi. (Paradigm Reference Studio or B&W CDM Speakers) and I'd like to bi-amplify.

Ideally, what I'd like to do is use a quality integrated amp (Audio Refinement, Audiolab, Arcam, etc.) with a second (matched, but more powerful) power amp for the lower frequencies, and also be able to use the system as the front end of a Home-Theater system.

What I'm wondering is whether or not I'm better off to use an active crossover (brands, anyone?) and bypass the speaker crossovers altogether (which would require some rewiring, but I'm going to do anyway, to upgrade the internal speaker wiring), or save on the signal path, and just split the pre-out to the two amps?

Any opinions?

jlafra3c2d1
I'll be making a rather large purchase from Marchand very soon. I need several crossovers and was already planning on using his products. It's good to see others on this forum came to the same conclusions about his products that a few others that i know have. There is something to be said for "mass customer satisfaction". Sean >
the marchand xm-9 deluxe is exactly the x-over i'm using, & 1953 is right - it's great, & it's wery flexible. i currently have it set to 60 hz, x'd over to a pair of subs. but when i can get those newform r645's i want, the x-over goes back to marchand for conversion to their 3-way model, so i can run the newforms in a true active-crossover bi-amped setup, as well as x'ing over to my subs...
One easy way you can actively bi-amp is by simply adding a powered subwoofer that has a good high pass x-over section. And there lies the problem. I've run into only two brands that offer "inexpensive" subs that have good (read smooth & transparent)internal x-overs. They are Velodyne and HSU. For example, you can get a brand new Velodyne FSR-12 for right around $900. The HSU's will be less. I have a pair of Studio Reference 20s in another system and they REALLY sing when you relieve them of low frequency duties. A better but more complicated approach is to buy a Marchand XM-9 deluxe x-over. It is a bit smoother and more transparent than the HSU or Velodyne x-overs and preferable to the Bryston 10B. This approach allows a broader choice of subs. By filtering out some lows, you can now use some of the more inexpensive but still excellent low power amps that are out there (like the Rogue 88) and still get good volume levels. Tube amps in particular (like the Rogue 88) become a real possibility. Did I mention the Rogue 88? Also , I would not be the least bit shy about openning up your speakers of choice and having a look inside at the x-over. My Studio Reference 20's x-overs, for example, are straight forward and should lend themselves nicely to being bypassed with the Marchand set to a 1500-1800 HZ symetrical, 24 DB per octave x-over. Another course is to bypass the internal, passive x-over and build another external passive one with the same component values but using higher quality parts. This approach is more time consumming but is definately cheaper and results in a less complicated system than a biamped one.
i would also check out diy crossovers here:

http://members.nbci.com/activecross/index.htm

if i wasn't already extremely satisfied w/my marchand x-over, i'd try doing this... sems like hi-quality for reasonable (cheap?) money...

Sounds like keeping it simple is best...thanks everyone.

But, the idea of building a set of speakers is interesting. Problems is, I worked in Pro Audio (sound reinforcement) and bi & tri-amplification is pretty standard. For awhile I had my old Paradigm 7se's biamped with NAD stuff, simply running the larger power amp to the bass set of inputs and my 3020 to the highs (using the internal crossover in the 7se to split the signal). I used a pink-noise generator and a Real-Time Analyzer(RTA) to set the balance for the room, and found improvements in detail, and tighter bass (was still kinda boomy, though). Since then, I've been thinking of trying the same thing with (somewhat) better equipment.

Oddly, its always been my opinion that with all the R&D manufactures put into their designs, that I could never approach anything they could build, yet I have a friend who builds excellent speakers/subs for pro sound reinforcement. I have the background in electronics, but not in acoustics, but I think it would be worth talking to him about it. The expense would be minimal, and the fun maximal, so why not?! I may suprise myself....

In the meantime, I think I'll be saving my $$$ for that cheapo YBA integrated (The Audio Refinement Complete), and biwire using some good cable (better than my current Moster Cable)

P.S. Thanks for the suggestion on the Richter Scale...looks like a lot of fun!

I'll try again based on you interest in experimentation. For mid-fi, you might also check out the Audio Control Richter Scale. If you really want to play, why buy speakers with design, parts, and labor included and then undo it? Why not check out Old Colony Sound Lab (Speaker Builder, Audio Amateur) or other souces of speaker designs, components, kits, and so on and do it all yourself?
hi cornfedboy,

have ewe checked out marchand? they make excellent, useful, uncolored x-overs, imho - also reasonably-priced.

regards, doug

I agree with all of the above. Most speakers are "voiced" to sound and perform a certain way with their passive components ( i.e. "crossovers" & "wiring") taken into consideration in the initial design. Altering those parts or changing the slopes or amount of "blending" that naturally occurs between the drivers can be an utterly disastrous thing to deal with. On the other hand, most products built to a price CAN be improved upon with CAREFUL work and planning. Like the others though, i would suggest looking at better basic components instead of trying to tweak or force components into something they can never be. Keep in mind that the fancier that you get in terms of "out of the ordinary" installations, the more elbow grease, trial and error and money it takes to make them perform to their fullest extent possible. It also requires tools of the trade and a good basic understanding of electronics and acoustics if you want everything to work right and last a reasonable amount of time. Remember, K.I.S.S. still applies : ) Sean >
all of the above posts are on target. when you start to consider really useful active xovers, you take yourself waaay beyond mid-fi. one of the few i'd consider is made by fm acoustics. read: switzerland. read: expensive.
1. There are no off-the-shelf active crossovers which will exactly match the needed parameters for the speakers. The only exception is the active powered option for the Paradigm Reference speakers. 2. In view of the above and in general, buy better primary components (amps and speakers) before considering complex and unnnecessary configurations.

The issue of being complicated is half the fun (I like to play with these things). As for a major step, I'm going to be upgrading from some old NAD stuff & NHT 1.3's over the next two years on a rather limited budget. I don't want a too unbalanced system, and I don't want to sink too much into a CD player before letting the new formats work themselves out...

I feel the most important step is a new amplifier, likely an integrated, and I can retire my old NAD 3020. But the truth is, I see an upper limit to this thing around $5k for everything (Not including Home Theater).

I think I'd put the money and/or effort into a fundamental step up in speakers and/or electronics if you could identify something that would suit you and your budget. You would probably get more bang. JMO