Review: Tube Audio Design TAD-60 Tube amp


Category: Amplifiers

I'll start by saying that I've been into higher-end audio for a few decades now, and quite a lot of equipment has been through my hands to this point (half the fun of this hobby). Somewhere around 12 years ago, I'd come to realize that I preferred tube amplification over solid state in terms of an overall involving presentation of the music, and ever since then have owned tube stuff (brief flirtations with various solid state devices only helped to enforce this notion).

Which brings me to the discovery of Tube Audio Design, the provider of components conceived by Paul Grzybek (of Bizzy Bee Audio fame), built to his specifications by a very reputable Chinese manufacturer, and then hand-finished by Paul in his shop located in Wheaton, IL. (His offerings are available exclusively online; detailed product info is found at http://www.angelfire.com/biz/bizzyb/index.html)

The TAD-60 amplifier is built like the proverbial tank; overall appearance and heft (not to mention its specifications) in my experience indeed belie the modest asking price. With its stainless steel chassis and almost 1/2"-thick black anodized face, the relatively compact package portrays a masculine but elegant stance (also included is a lift-off stainless steel tube cage). All function controls are easily accessible from the chassis top, as are the tube bias test-points and adjustment pots (a digital voltmeter is included too).

EL34-based, the TAD-60 is rated at 60wpc in UL-mode, and 30wpc in switchable-on-the-fly triode-mode. Other standard features include adjustable input sensitivity and adjustable global feedback, adding flexibility to a host of possible preamp and speaker combinations (the input sensitivity control may also be used as a volume pot in a single-source direct input configuration).

Listening to the TAD-60 after the recommended 30 hour break-in period and beyond, the music really began to open up, and along with the TAD-150 preamp, I was experiencing just about every CD I spun in a whole new manner - I'm particular to small-ensemble jazz and female vocals - there was an in-the-room conveyence of the music that I found startling at times - present is deep, tight bass, a glorious midrange, detail, depth, and an overall natural presentation that allows hour after hour of enjoyable listening. I've found that the feedback adjustment permits a fine-tuning of balance between dynamics and warmth, and was able to "lock in" the amp to my speakers for what sounds to be a perfect sonic match (just a tad of feedback along with the triode-mode setting seems to be the magic spot in my case).

Without attempting to describe every sonic attribute I'm hearing (though I'm happy to answer any particular inquiries), suffice it to say that the TAD-60/TAD-150 combination strikes a synergy and glow that is especially musical, and is among the finest I've had the pleasure of owning. The TAD-150 has already been highly praised in at least a few user and online reviews, and I bet the TAD-60 will soon be recognized as a similar standout. If you happen to be in the market for high quality, reasonably priced, excellent-sounding gear, just take a listen for yourself, and you will hear what these components can do for music. (Paul also offers a 15-day in-home trail period.)

Note: I have no financial interest or business relationship with Paul Grzybek or Tube Audio Design.

Associated gear
Magnepan 1.6QR, California Audio Labs CL-10, Music Hall MMF-5/Goldring G1012

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ggeers222
Thanks Larry, I also prefer the EL34s to the 6ca7s for the mids. The new Tungsol x7 works for me. Stan
And may I just add , that on both amps I am running 6ca7s, bass amp (hot bias) to squeez out as much power as possible to woofers and class A for mid tweet amp,which is very smooth. I am very critical of two channel audio and must say that the Tad60s are very good amps.
Stan
Hi Stan...Your comment about the tad 60 rings true because I have tried several el34 based amps, ie shanling, prima luna etc and this one just has something the others did not. Such is the mystery of this hobby.
Hi Larryrx7:

Where did you purchase your KT77s? I have been reluctant to buy them because of the reliability issues raised on AudioAsylum. Even Paul said he had a high failure rate with these. Some people seem to get tubes that are fine, but poor Jim McShane seems to get bad batches.
Thanks for your help.
Michael
P.S. I think the TAD 60 is a great amp and Paul a really nice person to deal with.
Hi MIchael....I think I got them from TubeDepot...So far they have been rock steady..and I really like the sound..larry
I have had my 60 since early may and I am most pleased. Others that have heard my system aggree that this is a very good amp. The 60 is just driving the top half of my Vandy 2ce Sigs. I am using JJ KT77's from douglas tubes with no problems, biased Class A. The mids and highs are sweet and fast. Other mods are: TubeCoolers that are grounded, I replaced the plastic feet with 3 2X3 inch brass footers and the whole thing is sitting on 4 inches of butcher block slab painted black that is spiked to carpet over concrete. I added some wood side rails and painted silver tran cap black.
Hi guys...I just purchased a pair of vintage Spica TC50's from a fellow audiogoner and have been listening to them through my tad 150/60 combo and am truly amazed at the imaging these 20 yr old speakers project. Does anyone else have any experence with this combo?...thanks
Just got my TAD60 from a fellow Audiogoner, I am using it with my new Mark and Daniel Rubys in UltraLinear mode. These are only 82DBL sens. and supposedly need at least 80 watts. Oh Contrare!! With the 60 Tube watts that this amazing amp puts out the sound and level in my 15X 20 room borders on Stupendous!! These Speakers were blowing me away before and now they are killing me!! This is a match made in heaven. I will never go back to my solid state amps after this combo.
Update: It's been just about 3 years since posting my TAD-60 review, and my TAD 150/60 combo still shines as brilliantly as ever. After the first few months of ownership I'd exchanged the stock EL-34 tubes with EH 6CA7's, and then later with Tung Sol KT-66's - A very nice transformation in each case with regards to bass depth & control plus added midrange holography & presence. And zero reliability issues to boot with either unit. Keepers for sure! -gg
I've owned my 60 for approaching 2 years and feel compelled to mention a little here of my experiences.

I bought this amp from a fellow A'Gon-er (Thanks V.P.!), it was my first tube related purchase in about 30 years. It arrived with 6CA7EH's and a quad of JJ KT77's. The AX7's were RCA cleartops and the AU7 was an RCA grey plate. I used the 6CA7's and set it up in SET mode. I really liked what I heard.

Since then, I have tried a few different AU7's including some Sylvania's, GE's and Mullard (Eico) ECC82's in place of the Cleartops, I always went back to the Cleartops. The sound has more clarity and the mids and highs shimmer in comparison to the "darker" flavor of the other tubes.

Over the past 18 months, in SET mode, I've tried the following tubes:

JJ KT77's, but couldn't get them to hold biasing, so I got rid of them, I understand that there were quality issues with the older ones and that these issues have been corrected with the newer ones. I haven't tried any newer versions (yet).

Then, I tried some Flying "C" 6550 from SED. The most obvious change that I heard was more bass, it was really nice, IMO. The highs weren't as shimmery as the 6CA7's. The mids were not quite as nice, either, but still sounded excellent.

The next roll were JJ E34L's at the suggestion of a guy at AudioKarma. Inexpensive to say the least, they are currently my favorites. The highs and mids are accurate and smooth, and there is no lack of bass, either.

I recently started to notice a strange sound in the left channel on power up, and it turned out to be my RCA Grey Plate AX7, :cry:. Fortunately, I had an Amperex and Sylvania laying around, and between the two, I preferred the Sylvania.

Fortunately, I got some cash for Christmas, so, of course, I had to spend it on tubes. I just ordered a Mullard reissue, Tung Sol reissue, JJECC803S and Sovtek LPS from Doug's Tubes. The fun continues...:)

At any rate, I really like this amp, and I enjoy the seamingly endless variety of tube one can feed it.

Adcom GCD-700
Adcom GFP-710
Adcom GFT-1A
Dual 1218
Teac A6010
Altec Lansing 604-8G's in 620B cabinets and Jeff Markwart crossovers
I would say this amp runs mildly warm. I run this amp all summer. If this amp is a good match for your speakers, I would give it an easy recommend.
I have been using my TAD-60 since 5/2006. Last year I changed speakers and the T-60 has been religated to biamp duty firing the upper half(Mids and Ribbon tweeter) of my rebuilt Magnepan IIIa's. The amp has no problem driving this low ohm load to high levels.
I lost an output tube this moring(they were JJ KT77). They were four years old, so I have nothing to complain about.
I have the original power tubes that Paul supplied but they are in an Dyna ST70 being used in another systemand I can put them back it the T-60 temporarily. So I am in the market for new Power tubes. Just curious if any one wants to point me in a good direction.
after much reading and advice from many I deciced on Ruby KT88's from Doug's Tubes. When tubes arrived I could not bias them correctly (they were running way to hot, even with the trim pots at the minium) With help and mch patience from Paul, I added a resistor to the bias circuit and now the bias properly with ease.
The new tubes sound very different from the JJ KT77's. The extension in to the high end is a welcome surprise.
I've always wondered how the KT88's would sound, as I've seen them in MC275's, so I assume they must be kinda "special." My SED 6550C's kick ass, but don't have the quality mids and highs of an EL34 IMO, only by a slim margin, though.

What are your impressions? And why the trouble biasing? I thought they would be interchangeable with the others; KT77, 6CA7, 6550, EL34, etc. I realize no 6l6 series because Paul told me they couldn't handle current.

I've had my TAD60 since 3-2007 it currently runs a second system in UL Mode with some very nice early KLH Six's. I use it more than my "primary" SET system. I am still completely in love this amp. Too bad more can't enjoy these wonderful gems, that's for sure.
I understand Paul has passed away and his web site is defunct. Do any TAD-60 owners have copies of the information that was on there? In particular the biasing values for various tubes, and ways to tinker with them such as lowering bias to effectively get SET amplification, and other instructions/advice. Would also love to know what else was on there.
Karimo40, send me an email f16125 at aol.com and I will fax/mail you the bias instructions
I have a writeup and complete biasing from Paul on my blog:

http://brianmedia.net/2013/04/tube-audio-design-tad-60-amp/

.
Hi all,
Anyone try new KT120s ? Do you think TAD-60 can handle KT120? I hear good things about these tubes :)
Thanks
You should try the overlord 12ax7-HD. these babies sound killer..
Others I recommend
ecc803s Telefunken More expensive.

I Just FINALLY found this straight from Paul G:

"> > Jeff,
> >
> > Class A instead of A/B can be accomplished in triode mode if you turn
the
> > bias up to 45mA per tube instead of 35mA. Doubt you will hear a
difference
> > in this amp - just roasts the tubes hotter. If interested you can run
> > singe
> > ended with tubes only on one side for each pair - this drops the power
to
> > about 8 watts, bias to 45mA (450 on supplied meter).

> >
> > Tube rolling is quite enjoyable with this amp. The (2) phase
> > splitter/voltage driver 12AT7's supplied are old stock US types.  The
> > supplied single 12AX7 is very middle of the road - this position is most
> > critical. I can supply your amp with my "famous" Chinese 12AT7 (same in
my
> > TAD-150 pre). This tube rivals Telefunkens & Mullards - internally looks
> > like a Mullard T7 knock-off but sounds even better.
> >
> > I'll note on your order no LED,  and to swap the X7 for a T7. Lots of
> > orders
> > to fill. The busy season for tube audio.
> >
> > Paul"

Posthumously from Paul!

COOL STUFF!!!