[Ray750]

Hello. I have the B&WNautilus 805 speakers (bookshelf) and an NAD c340 solid state integrated (50 watts). I have never owned a tube amp but am intrigued about what I hear about them. I have read that the Ultimate 70 can compare favorably with the best "cost no object" tube amplifiers. Is this accurate? My other option is the Insight 240. Any thoughts on which may sound better? Also, I assume that either would make a fairly significant difference? Thanks in advance!

[gjs_cds]

I was tube curious.  So I dropped a grand on a decent tube amp.  I realized that they're a hassle, and don't really sound "better" than a good SS amp.  You may pick out some subtle differences, but I wouldn't say "better".  Further, they may be out-and-out inferior relative to damping. 

I'd go w/ the Insight w/o hesitation.  Although, I can't blame you for being tube curious.  I was tube curious.  I experimented with it while at home alone with the lights off.  It was fun at first; new and exciting.  But it wasn't as satisfying as I thought it would be, and it lost it's appeal over time.  Now, it sits essentially unused.  My AVA SS gear is used for at least 6 hours every day. 

'nuff said ?

[BrianM]

I'd be curious to hear an Ultimate 70 myself. But I would assume if Frank could make a pure tube amp sound as good as his latest SS and hybrid designs, he'd have one in his current product line (as opposed to just rejiggering old Dynacos).

p.s. I said "sound as good" when it would probably be more accurate to say "sound as transparent."

[cdorval1]

I listen to an Ultimate 70 in the daytime while I work.  I like it lots, which might mean I am one of those somewhat irrational tube guys.  The sound is very involving, especially on voices--it's easy to stop what I'm doing and take a few-minute break to just listen.  By the way, I'm also using a tube preamp (Super PAS 3), which has lots to do with it.  Another consideration is that the power needs of my working situation are not huge.

I also use an Omegastar 240ex--one generation back from the Insight--with my TV.  It also is an excellent amp, which I switch out with the U70 every once in a while.  If it weren't for the demands of TV audio, I'd use the U70 all the time.

I'm not sure it's a better/worse situation.  It's more personal preference--and the power needs of your situation.  I've listened at length to the 805s, and my guess is they'll love tubes.  Others will share their opinions, I'm sure.  If you want to try tubes, the Ultimate 70 is an excellent value.  By the way, it's not a "rejiggered" ST70--except for the transformers and chassis, it's a completely Van Alstine amp.

Have fun!

Craig

[BrianM]

By the way, it's not a "rejiggered" ST70--except for the transformers and chassis, it's a completely Van Alstine amp.

Yeah I know. By rejiggered I just meant changed.

[charmerci]

If SLAM BAM bass is important to you, you have to go with the Insight.

[martyo]

Charlie's right, but w/bookshelves you might want that "killer liquid midrange"................Fun choices for you. You have flexibility not needing mega-watts for the bottom octave.

[Art_Chicago]

Hello. I have the B&WNautilus 805 speakers (bookshelf) and an NAD c340 solid state integrated (50 watts). I have never owned a tube amp but am intrigued about what I hear about them. I have read that the Ultimate 70 can compare favorably with the best "cost no object" tube amplifiers. Is this accurate? My other option is the Insight 240. Any thoughts on which may sound better? Also, I assume that either would make a fairly significant difference? Thanks in advance!

Hi, Ray750, I still have a NAD 340 running Rogers LS88 in the basement home theatre setup and the system sounds pretty good. I have not heard  U-70, but AVA SS are great amps, my OmegaSTAR 260 made a BIG difference! It is much faster, dynamic, even liquid and has a deeper bass than NAD 340. You would hear the difference playing anything from a rock to a large symphonic orchestra.  Later I added a T-8 tube preamp, and I love this combo! Chamber music is unreal.
What preamp are you planning to use? The NAD preamp section? It is not up to the AVA level, I think.  You may want to spend some more and get an Insight Control-- 90 W/ch. Also, I believe that Frank does not sell U-70 as a new complete unit, you need to provide an old unit for the upgrade, but I am not sure.
Anyway, Good luck with your search!
Art

[mark funk]

I heard a U70 with a T-8 (before the 6N1Ps) and Salk HT-2s in 06 RMAF. When I came in that was what was playing, I did not know at first what was playing, I listen for a time until Frank changed CD and said what we were listing to, I though it was the Ultra stuff .  

[Brett Buck]

Hello. I have the B&WNautilus 805 speakers (bookshelf) and an NAD c340 solid state integrated (50 watts). I have never owned a tube amp but am intrigued about what I hear about them. I have read that the Ultimate 70 can compare favorably with the best "cost no object" tube amplifiers. Is this accurate? My other option is the Insight 240. Any thoughts on which may sound better? Also, I assume that either would make a fairly significant difference? Thanks in advance!

   I have a U70 and a Omegastar 260 (not Insight) and it's all just my opinion, but I think the answer will be roughly the same.

    At reasonable volume the U70 is as good as any tube amp I have heard, and that's a lot of tube amps. It does have a "sound" (which is bad, amps shouldn't have a sound of their own) but it's much more neutral than any of the others I have heard. It's incredibly superior to a stock ST70, don't think of it as a modified ST70, it's a new design amplifier than uses some ST70 parts.

   The only tube amp that I have heard that was actually a net improvement (in my opinion) was some gigantic VTL monstrosity that didn't sound as good overall at moderate listening levels but had so absurdly much more power that the dynamics and bass control were better, and it would get far, far louder without obvious distortion. Too loud for my comfort, actually, but it wasn't mine, I was just listing to it.  At a typical listening levels the U70 was far better, far more neutral. Craptastic mega-dollar SET amps, not even close.

   But after a fair bit of back-to-back with the Omegastar, it's really no contest, the Omegastar beats it hands down. More neutral, particularly in the "killer midrange" area that sounds pleasant on the U70 by having some effect on the sound by not being neutral. But it's really across the board, far, far better deep bass control, far better and more detailed high end. Not really even a contest, the U70, while as good as it gets for tube amps, still sounds "tubey" compared to the Omegastar. Of course the dynamics are better, too, since you have almost 4x the power, and effectively more since you can keep throwing the current to it at low impedances.

   If you bridged two U70's then it might be a different story, but one-at-a-time in a conventional system I don't think it will be any contest.

    Brett

[Wayner]

Brett and my story are close. I have the Ultimate 70 and the Insight 260. Both fine amplifiers. Both different missions. Both have a little different definition. With high efficiency speakers, the U70 at normal listening levels is killer. With slightly less efficient speakers, the 260 is killer, obviously more power, more dynamic. I let them be them selves. I do like listening to classical music on the U70, and rock on the Insight...but that is just me. The one factor is that the solid state doesn't require the occasional tube replacement, which is a cost burden.

Wayner

[Ray750]

Thanks for all the great info.
How efficient do the speakers need to be for the u70? Thr B&Wn805 is 88spl, but a Stereophile article says they measured them at 85.5, but said that they are an easy speaker to drive, with a minimum impedance of 4.8 ohms at 200hz and a generally low phase angle other than in the upper bass. Im not relly "techy" enough to know what that means. At age 55, i usually dont listen too loud.

I also have a Zigmahornet that I built (93spl single driver) but those arent up to the B&W. It was an inexpensive experiment.

[Wayner]

I'm running some Focal JMLab 908's which are 90db and some Dynaco A25XLs which are 91 db. I would consider a 88db speaker to be medium. Every 3 db  of gain on speakers really improves amplifier power.

Wayner

[martyo]

I just noticed you are now driving your B&W's with 50wpc ss integrated. If that is enough juice, 35wpc of tubes should be fine.

[OldCoder]

Ray,

I've listened to B&W 805s a lot, and they really like power.
If you want any "umph" in your music, I think you'll be happier with the Insight.

The U70 is a great little amp, but it will run out of gas on a big
swing band, loud rock or orchestral crescendos with the 805s.

If you plan on running subwoofers and an electronic crossover with the 805s,
the U70 might be enough for the 805s as satellites.

As long as you match the power requirements of your speakers and listening desires
to the size of the amp you get from Frank, you really can't go wrong.

[rlee8394]

I have used two U70 amps with Frank's Phase Inverter Bridge to drive my B&W 801FS loudspeakers. Each was built by me with all parts matched channel to channel and amp to amp to insure exact channel balance. I also built them with Triode Electronics replacement power transformer which yield approximately 40 watts/ch. Bridged they would be roughly 120 watts/ch, which drive the 801's just fine!

Ron

[simon wagstaff]

I have a u70 and it is the finest amp I have heard in my system. I am driving Infinity IM 4.1 though so the amp isn't seeing anything below 80 hz. the midrange and depth are unbelievable. I would have to agree that if you have a sub or two and can cross over the B+Ws so you restrict the low frequencies you should have plenty of juice. Volume is not a problem for me. the U70 is a wonderful amp and think it would be a great match, giving you a nice liquid midrange and lots of image depth. Slam would need to come from the subs....

[boycephoto]

Hey Ray,

Have you decided which amp you are going for? 

Dave