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

Similar products
Conrad Johnson MV55
Sonic Frontiers SFS-40
VTL 50/50
Golden Tube SE-40
ASL AQ-1004
Sound Quest SQ-88
ggeers222

Showing 7 responses by meerp1

Hi,
For those of you that have rolled the TAD-60 with KT88's what did you set your bias at? Paul's site states 600-625. Just wondering if this is the same with all mfg's. Just thought I'd give Paul a break and ask the forum. I imagine he spends a lot of time replying to customers. I'll post my thoughts on the Penta KT88's once they burn in a bit. Thanks!
Jeff
Ldaltof,
Thanks. I thought that was the case. I'm having a problem with my bias pots at this time so I'm kinda stuck at the moment. Left channel won't cooperate and is excessively hot. Not the tubes to my knowledge as I've rolled several with the same result. Any way to calibrate the bias pot? I did email Paul, hopefully not a painful remedy.
I also have the TAD-150. I'd like to try other tubes in that unit. Thanks.
Jeff
Ldatlof,
I got the Penta 88's up and running but it took a little tweaking. I normally would Bias with the Feedback fully right but that was not possible. Actually the left channels, V1 & V2 run quite a bit hotter than the other side. V1 has a reading of 635 at its lowest point so that's where the quad is Biased at. If i turn the feedback all the way up the left channels will oscillate, run excessively hot, and shut the amp down. I had one happy fuse "blown". So I tested a lot, being more careful and finally dialed it in. Paul was helpful. I still may send it in in the future to get a bigger range with the Bias while using 88's or 6550's. Currently breaking in the new tubes and it sounds very good. Thanks for the reply. let me know if you have questions. I'm sure I'll have some.

Jeff
New Finding on my oscillating problem. With speakers connected my Feedback knob will function full range with no problems. I read where it's best to have speakers connected on tube amps. Here's what I read, "An output transformer stores inductive energy, and a speaker load prevents this energy from being returned to the tubes in the form of high-voltage transients."

Jeff
Paul has some new bias settings on his site that should be worth trying. The new settings will provide Single Ended Class A for the first 10 watts and Class A/B for 10-50 watts.
Dave, I'm using the Penta 88's also and find them to be a good sounding tube. What are your impressions?
Jeff
Dave,

From the bias levels it would be used for the EL34's. I did try it with my stock tubes & it did sound nice. Especially in the mids. Worth a try. Nice to have alternatives.

Jeff
I tried the Class A Bias with good results. Most noticeably the mids sounded great. I may even try & mix the 34's with the KT88's.

Jeff