Biwired-Dunlavy V- Bass reduced why?

I got these new cables (one each hi and low pass) that hooked up to my Dunlavy V 's for the very first time. While mid and highs are improved few nothces, bass qty (actually quality at first impession is quite good) reduced dramatically.

Could you expalin Why? Do need Jumpers also?


You won't need jumpers. I'd say your bass reduction has got to do with the new cables. Different cables different sound.
Hopefully you have tone controls and can boost the bass.
I agree with Nuguy that no jumpers are needed and that the decrease in bass is probably related to the new cables.

You can try a couple of things before giving up on the cables. One thing would be to invert the bass and midrange legs of the cables to see if that makes a difference. In other words run the "tweeter" wires to the bass section and the "bass" wires to the mid/tweet section.

Another thing to try would be different interconnects between your components. Start with the pair between the preamp and power amp and see what differences you notice.

Trial and error is the name of this cable game. Unless you just want to cut your losses and go back to your previous cables, why not do a bit of experimenting to see what results you can achieve?
Are you sure you didn't reverse the polarity on one of the woofers or the wires are mislabeled? Reverse the leads to one woofer and see if you get more bass.

Maybe you had too much bass before and now it is the correct level?
Thanks Nuguy. It definitely the new speakers cables/biwiring scheme since it is consistent with all sources. And these are the latest try out. No tone controls :)

Would it be detrimental if I ADD jumpers WITH Biwires? How does biwire work?

I will try switching, but so far connections looks good.

Herman, I just measured test tones and it reveals that there is big DIP at 50-63 hz of appx 4-6 db! while rest of the bass within 2 db al the way down to 25 hz. On the other hand I had 4-5db peak thru all the bass freq thru 100 hz. (1000 hz as reference) . Now it is pretty much good balance except that dip and may be dip here and there at upper mids, but not to worry.

Strange thing is this cable are same make as all the ICs I changed out. My listening tells me that these cables gets me that elusive high end sound (life like mid bass, deep low bass when present in recording, musical mids and just enough highs not to sound like hifi) except the bass dip. So may be it is not the cables themselves but BIWIRING. May be I will try same make single wire with jumpers to get simialr sound without the dip.

Should I try jumpes in conjuction with biwire or would it blow something? Sorry, When I am desperate I talk stupid when it comes to audio!!
Try using one set of cables with the jumper. If it's the same problem, it may be that the cables are built that way. Some may call them defective....

Try using your old cables on the low pass.

This is the way that I have mine set up: Anti-Cables go to low and high pass. 99.9% pure silver cables go to high pass. It gives me the best of both worlds.

Good luck!
hmmm ... new cables typically need some time to break in.
Play them for a month - I've had two different pair of new speaker cables which both changed significantly during breakin. They'll probably 'come & go' for awhile before finally setting in.
As Bob mentions cables do have a break in time .....

On a second line of thought are the speaker cables the only change made recently to your system?

Maybe in the meantime you can change speaker position to "recover" some bass if willing to wait for the break in period and hope for the best.
Hi Bob, That kind of does makes sense now I think back. These cables have may be 20- 30 hrs burn time on them. At first hook up it was other way around, bass was predominant and highs were rolled off. Now mids and high seems to have settled but bass has a little kink...

May be I will burn them more...

You definitely do not want to use jumpers when you bi-wire. Speakers that are designed to be bi-wired sound much better when you run them that way. With speakers that just have a second set of terminals, it makes little or no difference. The Dunlavys were designed to be bi-wired. One of the benefits is that bi-wiring bypasses certain components in the crossover, which increases transparency and might also improve dynamics. In any case, don't use jumpers.
Single wire with jumpers OR biwire without. Using jumpers defeat the purpose of biwiring. Like 9RW says biwiring is just a more direct signal and there is less curcuitry for the signal to travel through. Just a suggestion but you should do a search on the Behringer DEQ 2496 in these forums. It is an inexpensive EQ/ room corrector with a ton of features. I use one and it took my sound to a whole new level. It'll run you around 400-450USD with the mic. It will make a HUGE difference.

Thanks 9rw. I looked in past threads but could not find much onfo on Biwiring 'crossover mechanism' but did not find enough info.

I played with my upstairs Dunlavy IV (easily accessible) which i use with jumpers and lower terminals. Since hi and low pass terminals are not labled, I experimented. I removed jumpers and hooked speaker cables to lower terminal only, thinking that only woofers will sound but no sound came out at all. Similarly I hooked speakers cables to upper terminals only thinking that mids and highs will produce sound, but once again no sound came out!!

So how does the crossovers (high and low pass) works with biwired cable without jumpers? Does two pair of cables connected to upper and lower terminal acts as jumpers thru amp connection at the other end?

Which terminal are high pass and which ones are the low pass?

i suggest you try a jumpered, single-wire configuration with your new cables and see if that makes any difference in the bass. This means you put the jumpers in and connect both + leads to one of the speaker's + terminals and both - leads to one of the - terminals. This should help you diagnose whether it is the cable or the biwiring that is giving you less bass than you used to have.

Your experience with trying just the one set at a time and not getting any sound at all is curious.
Thanks Drubin, Sol322 , Themadplatter and Nuguy for more suggestions/diagnostics. I will try out each.

I have changed out all the ICs (phono-pream, transport-DAC-preamp,preamp-amp) with the same make which I am extremely happy with so far. Even the speaker cables that am discussing in this thread also from same make and as I said earlier otherwisw produces sound that I did not think was possible. Except for this bass suck out at 50-60 hz. I should give it more time since both my analogue and digital source produces comparable (quite a fit) sound!! My mind is telling me something good happening with these cables and am trying to understand/read in to this new found warm but transparent bass performance. Strings are sounding oh so wonderful. Acoustic bass is very warm ( CGR like) but with enough definition up mids and uptop details. That 50 hz deep is noticable, for example when I play 'thump thump' music and there is not enough 'thump'.

I will give it enough time since i think I have a good thing going here. I will talk to the cable co designer tomorrow whoes cables(ics) have lived up to more than its reputation and the designer himself has gracefully helped me out thus far.

The lesson I learned from this experience is that I do believe that no one should skimp out on cables and like th cable thread 'double your pleasure' documents you do eliminate lot of funny stuff when you use one make and model cables. Even different model from same cable, IMO, skews things. If you have not got the right cables , you are missing out your other components performance potential.

Anyway Thanks all. I will keep you posted and reveal the cables/IC make soon.
Well, I found out for certain that Biwiring Dunlavy's reduces bass but increases transparency and clarity.

I tried my old cables with upstairs Dunlavy IV whicj also has same cable, same length. So I removed jumpers and biwired and yes indeed biwiring dunlavy does reduce bass v/s using single cable and jumpers.

Downstairs with Dunlavy V the new biwired configuration is still being burned in. But I did my measurments again using test tones and like Bob says it comes and goes. Today it was around 100 hz freq where there was may be 3 db deep. while 50-60 hz was filled up!! Also bass reduced impression is true, the measured bass now is 'flat' compared to ~ 4 db boost that I was used to with my old cables. So may be overall balance measures better which I just have to get used to or get a single new cable and use it with jumpers.

What are you using to drive the Dunlavys?

The change from biwiring is equivalent to a few microhenries, a few pico-farads and a few milli-ohms difference compared to single set of regular cables and binding post jumpers being in the circuit. Given typical speaker X-over networks we are talking differences of less than 1% in equivalent circuits.

To most SS amplifiers this should be no sweat. Such a small difference in X-over might affect a narrow range of frequencies at the xover but why such a big difference in bass, as you report?

Perhaps something else is going on that you have not accounted for...some kind of resonance or ringing between bass driver and amplifier that is tempered with this small change?

(Further food for thought; John Dunlavy was outspoken that he did not believe in large audihble differences.)

I am using Classe CA-400 in stereo mode. I agree this amp can drive any load.

Mr Dunlavy/reviewers in the past claimed/reported no audible change between single and biwiring and that the two terminals are mostly for bi-amping.

As i said in previous posts, I wanted to believe it was new speaker cables with V's, But with IV's using my well broken old cables biwired also showed relative reduction(actually you can think as removal of bass hump)in bass decible.

Is resonance or ringing you describe common phenomena? what are the indications that this happens other than lower bass db?
The Classe CA-400 with low output impedance/high damping factor (over 100 I would expect) should have no problem. It should sound great with either of your configurations.

It should not make a huge difference as you report (I trust Dunlavy's belief on this matter which is why I am just as puzzled as you are.)

As Herman suggested it possible somehow that you are wiring the woofers in opposite phase when switching to the biwired configuration?

If you suspect this then try reversing one wire pair to one of the speaker woofer bindposts (reverse only at one end and only on one speaker). See if teh bass comes in more strongly.
Shadorne, The connection are correct. Let me dwell on this a little longer.

May be it is the new cables with Vs. Or may be lack of complete distortion at low freq coupled with increased transparancy ( very apparent using same old cables with IVs) percieved sound to have lower bass.

Or may be I made mistake in measurements or reducing the data. I do trust Mr Dunlavy's claim. My old cables are Dunlavy DAL Z8s and have kept it all these years.... Isn't this hobby fun... er pain in unowatt sometimes?
Here's a real dumb question - have you moved your speakers or your listening position, or both? If you have that could well be your problem. FWIW.
Mistery solved!!

Well, Biwiring does NOT reduce bass db but only quality. with my IV's with my old cables, I was comparing uncorrected Ratshack meter values to my previously measured single wire corrected ref. I did not realize untill test I did just 20 minutes ago from scratch: with single wire and with biwire. Both numbers are exactly the same.

Downstairs with V's it must be the new cables!!

Sorry, did not mean to mislead anyone!!! Thanks to thoes who answered to the thread.
You have outstanding speakers and an oustanding was a mystery indeed that this high quality equipment should be so affected by a change of cable. Well designed equipment should be robust and tolerant of such slight changes as the differense from a cable.