Def Tech w/ tubes?

[ski2xblack]

I have a pair of DT BP7006's for music only in the living room (love 'em, by the way). They are currently powered by a vintage ss amp, but given their relatively decent efficiency (92dB@1W/m), and the fact that they have built in powered subs, I am tempted to try them with tube amplification. They seem to be begging for this treatment.

Has anyone tried the Def Tech/tube amp thing? Particularly using DT's w/ powered subs. Any feedback? Lemme know, and thanks for your input!

 

[GlocksRock]

I have my 7006s and 7001SCs all amped, but not with tube amps, but I do think it would be a good match... the warm sound of a tube amp combined with the bright sound of the def tech's should be pretty good. Go ahead and try it and let us know your impressions.

 

[ski2xblack]

Thanks, Glock. I will definitely provide feedback when I pull the trigger.

I'm not looking to spend too much for this experiment. I noticed the Wave25 from Antique Sound Labs; it's a 20w push/pull type mono amp for $350 or so. They are so inexpensive I'm tempted to get a couple and try them.

However, it seems prudent to try and get some feedback from those who've already tried such a setup. I suspect there are a few DT'ers using tubes lurking around here...

 

[ski2xblack]

my impressions are positive

Bought two Decware Zen Se84C+'s for the 7006's. Strictly stereo.

Impressions are:

...wonderful SET clarity and imaging, extremely well complemented by the 7006's inherent imaging prowess. Think 'walls-vanishishing', 'holographic', real goosebumps territory, no joke. If you've never heard a SET amp, do yourself a favor and give one a listen.

...flat, deep, full range response, thanks to the 7006's built in sub; I think this is one of the areas where this combo has one up on the hyper-efficiency speaker/SET approach; they tend to roll off much higher and require a separate sub (or be ginormously huge) to produce full range sound; the DT's are pretty idiot proof in this sense, and their very well integrated subs perform quite sufficiently. I'm feeding them high level tubified signal only, and this sextet of 8"ers seems to be highly capable. Even if I'm only getting 92db from that precious first watt, it is at least a full bandwidth 92db.

...limited absolute output (which is why I opted for two Zens), but pretty much sonically unassailable within it's performance envelope. With the two amps, I can achieve quite satisfactory volumes, near 100db out in the room when clipping occurs. That's pretty loud, plenty for me, but maybe not enough for others which is why I mention it.

...I'm probably missing out on some of the microdynamic detail which hyper-efficient designs offer, and I can't achieve concert sound pressure, but it would take speakers rated 100db/w/m with these amps to do so. That being said, the 7006/Zen combo easily surpasses my ss amps when it comes to speed, imaging, realism, and dynamic impact.

...I've listened to a couple other tube amps recently, and compared to other SET's, the Zen's seem less 'tubey'. A bottlehead paramour kit powering probably ill-matched speakers was producing the classic chimey tube honey and flabby bass, which is notably absent in my Def Tech/Zen system. The DT/Zen's really disappear from the music, leaving only phantom musicians and their music to surround you. It's mezmerizing.

 

[GlocksRock]

Thanks for the great review, glad you are enjoying them. I really wish I could hear your setup.

 

[ski2xblack]

Thanks for the great review, glad you are enjoying them. I really wish I could hear your setup.

From the looks of your sig line, you've spent about 10 times what I have on audio hardware(!!), so you're clearly not bashful about buying equipment and could likely afford to try out tubes easily enough. I posted this stuff specifically for folks like you. If, like me, you are curious about the tube thing, your DT's should work surprisingly well with SETs, provided you aren't expecting rave-party volumes. And there are some very reasonably priced SET's out there, although I can only speak with confidence about the Decware's I own.

 

[bandphan]

Have you done any sweeps to find out exactly the range in the upper and lower without the built ins? Im intrested in the single ended output

 

[ski2xblack]

Have you done any sweeps to find out exactly the range in the upper and lower without the built ins? Im intrested in the single ended output

http://www.decware.com/zenb&k.jpg

That's a freq response graph from the Decware site. Looks like it starts to roll off around 30hz on the bottom, and fairly flat to 20K, -2db looks like ~25-23K. I generally avoid torturing my speakers with test tones/sweeps and such, but I haven't heard anything that would lead me to question their published response.

 

[ski2xblack]

bandphan, I notice you have fostex listed in your sig. You should definitely try the SE thing on those.

 

[GlocksRock]

From the looks of your sig line, you've spent about 10 times what I have on audio hardware(!!), so you're clearly not bashful about buying equipment and could likely afford to try out tubes easily enough. I posted this stuff specifically for folks like you. If, like me, you are curious about the tube thing, your DT's should work surprisingly well with SETs, provided you aren't expecting rave-party volumes. And there are some very reasonably priced SET's out there, although I can only speak with confidence about the Decware's I own.

I bought all of my def techs used, so I saved a ton of money there, but the subs were bought new. I don't think I will mess with swapping out my amps, I don't have the time to mess with that right now, nor any more room for extra equipment. Plus it's a major pain to move my stuff around to get the the back of my receiver. I'm glad you are enjoying your setup, it's so pleasing to have things just how you want them.

 

[bandphan]

bandphan, I notice you have fostex listed in your sig. You should definitely try the SE thing on those.

the D5 in my sig is a master DAT recorder, however ive run the FE206E fullrange before. Ive also owned a few tube pieces over time including the macs mc250st & mc75m,, heathkit a9, and a dynaco st70.. If I ever go back to that sound, id go for a tub pre and keep the solidsate amp more than likley.

 

[ski2xblack]

the D5 in my sig is a master DAT recorder, however ive run the FE206E fullrange before. Ive also owned a few tube pieces over time including the macs mc250st & mc75m,, heathkit a9, and a dynaco st70.. If I ever go back to that sound, id go for a tub pre and keep the solidsate amp more than likley.

If you do ge the itch, I think some of the newer faux (as in 'not DHT') triode SETs using those SV83 pentodes wired as triodes give a very linear extended response more similar to ss than other dht's, and would likely be quite different than the tube items you mention (which, if I'm correct, either bigger push/pull types, or use lots of neg feedback-i.e. the Dynaco). Of course I've only had direct experience in my home with the Decwares, which I think this describes fairly well, but otherwise this is guesswork based on the internets. In addition to the Decware amps, there are lots of designs out there which are similar, seems to be a recent trend of many of the boutique tube producers. I think there is something to the no-neg-feedback circuits of these minimalistic SETs, which I'm pretty sure is markedly different from what you listed above. Unfortunately they also have far less power than the items you have experience with, which is the rub with the SET thing...only esoteric high efficiency speakers are ideal, otherwise you are severely compromised somehow or other. Like with my Def Techs, the Decware SETs work beautifully, but just barely, and if you need it loud keep shopping.

I'm not sure if using a tube pre with ss power amps would yield the same transparency/goodness as that of a SET amplifier based system. From what I've learned (I could be wrong here), but isn't the SET's startling speed and immediacy gained by virtue of the class A amplifier circuit? And even if you used a class A ss amp to preserve whatever tube signature on the signal from the tubed pre, wouldn't you still ultimately face the unfriendly odd order harmonics typical of ss amps? And would you really want a 'tubed signature' anyway? (The nice thing about the Decware amps is their utter transparency; they add no character at all that I can discern, they just play music pure and simple, not really tubey sounding, just crystal clear.)

Sorry for the ramble, Bailey's and coffee in full effect!