Subwoofer Crossover Replacement for Wilson WHOW?


Recently, I upgraded my system with super high-end power cords and AC line conditioners. (My system: Jadis JA80 tube monoblocks driving the Watt2/Puppy; and Krell KMA 160 amp driving the Wilson WHOW subwoofer) With increased resolution, I became aware that the low end of the spectrum is not as quick, detailed, or transparent as the rest of the spectrum. I concluded that perhaps Krell's 160 watts are insufficient for the WHOW. In communicating with a couple of WHOW owners, I learned that they solved their WHOW problem primarily by replacing the Wilson crossover with one that comes only with balanced inputs and outputs. Since my front end does not have balanced outputs and my amps don't have balanced inputs, I'm looking for an excellent subwoofer with RCA inputs and outputs. Any help will be greatly appreciated.
puremusic
Puremusic,

Well, I do not think that the problem of your system with “balanced inputs” or any other abracadabra that audio people managed imagine in their ultimate lunacy.

You did not named what specifically frustrates you in your bass. The phrases “quick, detailed, or transparent as the rest of the spectrum” are not indicative; at least I do not understand them. Looking at what you said I would give you a few tips and you figure out yourself how they might be applied in your satiation.

1) AC line conditioners are fine but NONE of them (and I had practically all of them) can handle the lower bass properly. The best of them would create the “impressed” bass but it you listen serious music and do not have barbarian or corrupted audio taste (most of audio people do) then you might fine that the line conditioners (including the isolation transformers and etc…) might not be used. The high bandwidth dedicated power line unfortunately is the only way to go, at least for lowest bass.

2) None of the Krells ever were capable of correct bass. The Krell’s bass is a noise of Niagara Falls – it juts a low frequency noise. It is hard to say what wattage you would be sufficient for this woofer. It would depend from the size of your room and the specific driver that Wilson people used in there. I think Wilson had 4 different versions of this woofer and only one of them used a good driver. If you lucky to have the model that use 1808 driver then you are in good shape. That sucker needs a lot of power if properly used however in your ported situation it might not need so much. It is very hard to estimate and only you might be the judge. Get better amp bit cleaner bass and THEN judge if you have enough power.

3) Wilson crossover should be trashed right her at the Audiogon aftermarket. Those crossovers kill bass with the force of a nice hurricane. Use whatever crossover you have to find the correct cut off and slope and then go to line level-passive right at you power amp input (or built it in between the stages). The important do not make the crossover to drive even one inch of cable and do not load the crossover with own PS and buffers. Thos thing are very bad for bass. Unfortunately the WHOW-type topoly will force you to go for higher order filter and it might bring own complications in the building-in the crossover into your amp but it still manageable and for the money you sell the Wilson crossover you should be able to recruit a technician to do the job, including the passive channel mixing.

4) Think out of bass in term of amplification for this thing. You might look at a single Lamm M2.1. I think it was near 240W and I have seen how the SS Lamm turned on the bass shiny speakers. If you lucky you might find one single monoblock… Look for old production of those amps when Lamm did not saved money and paralleled output transistors in sufficient quantities for a given power and ran it at higher current. His later production was kind of funny: the chasses and the radiators had slots for the paralleled translators but the translators were not there… The Lamm new version of this amp. I think it called M2.2 but I am not sure might be acceptable but I really do not know as I never listen them seriously. However, despite that some of the Lamm’s amp do not do anything “audio spectacular” in bass but certain things Lamm dose with bass dynamics very properly and it is what I might suggest you to do. As an alternative, perhaps the VERY ridicules alternative you might looks for high voltage direct coupled OTLs. Yes, they are horrible performers and particularly in bass dynamics but ironically in your case they can do. Since you cross your woofer somewhere at 25Hz you would be able to run such OTL at LF transition slop and it you have enough power to burn then it might be very interesting…

Good luck and have fun.
Romy the Cat
*** … they are horrible performers and particularly in bass dynamics but ironically in your case they can do. Since you cross your woofer somewhere at 25Hz you would be able to run such OTL at LF transition slop and if you have enough power to burn then it might be very interesting…

I have to add that the transition slop would resolve the “size” issues of the OTLs but you will need to play with the imp dace of your driver to made that OTL be able to hand the acoustic-like decay. Theoretically it is impossible, as any passive driver-level element of impedance equalization will kill bass but in your case of the “bizarre” Wilson sub it might work as the WHOW is kind of “strange” Lf section to begin with…
Nsgarch, this is not the place to promote your business. If the rest of us can abide by the posting rules, so can you.
Correction: One of the two WHOW owners referred to in my post informed me by email that the crossover he replaced Wilson's by has both RCA and Balanced inputs and outputs. It's the Krell KBX. So, if I can find it on the used market, that would definitely be a candidate for my short list of crossovers to audition.

Nsgarch: Although I am initially looking for a replacement for my crossover, I am also looking at the different alternatives for a higher powered amp. In fact, both of the WHOW owners reffered to in my post also obtained high powered amps. The Bryston 7B SST, Parasound Halo JC1, and the Crown K2 have been recommended by different people for my short list.

Rbes: My new dedicated listening room is 23.6"x20.8"x8.9". So, more power will help. Even with three 20 amp, dedicated AC lines coming into the listening room, the new power cords and AC line conditioners made a big difference. The subwoofer is on it's own dedicated line, as is the front end. The Jadis amps are on the third dedicated line. The cords and conditioners, of course, are not in the signal path. With them in place, the sonics are much cleaner, the noise floor is much lower. Consequently, there is now greater clarity, transparency, and discernible detail. The harmonic texture, nuance and delicacy of music is now more apparent. In short, I am now happier with the overall resolution, musicality and involement. The weak link is in the bass. At this point, I'm open to any and all suggestions for my short list: passive or active. In the end, auditioning by the ear/mind/heart will decide which combination of the candidates on my amp and crossover short lists is most satisfying to me musically and emotionally.

Best Regards,
John
Essentialaudio, I have no idea what you're talking about. The ad I referred to is not my ad and I mentioned it only to illustrate the kind of amp another person found satisfactory, that's all. Perhaps I should've edited out his identity, is that what you mean?

Puremusic, the reason I mentioned Bryston, is that new or used, they offer a lot of clean reliable (20 yr warranty) power for the buck -- especially in low frequency apps. I just thought that before you try other remedies, it would be easy to swap the amp you're using for a higher powered one. It doesn't even have to be what you would buy, an old SAE would do. That's a big woofer in the WHOW, and to get clean bass, it needs really good damping control, and that's one thing a high powered SS amp gives you. Even at low volumes, an amplifier is called upon to provide power peaks at each end of the cone travel in order to maintain good control over the cone when its direction of travel reverses.

In your post you said the bass was not as "quick, detailed, or transparent as the rest of the spectrum." So if everything else about it is alright (volume, freq. response, blending with the main speaker, etc.) then I'd put my money on the power issue and look to the amplifier first -- plus it's an easy thing to check without a lot of fuss. Just give it a 400W amp and see what happens, you can't hurt anything.