Old AVA equipment revisited

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avahifi

Old AVA equipment revisited
« on: 3 Oct 2018, 08:55 pm »
We got in a couple of pieces of nearly antique AVA equipment this week to test and repair as necessary.

The preamp was a 1988 production Transcendence Two discrete transistor preamp built in a Dyna PAT-5 chassis.

The power amp was a 1988 production Transcendence Two discrete transistor 140W/Ch power amp built in a Hafler DH-220 chassis.

The preamp's only problem was a frozen power switch and a few signal dropouts in some of the controls.  I replaced the power switch and cleaned all the controls, switches, and jacks with DeOxit and now it runs like new.

The power amp's only problem was blown power supply fuses on one channel.  This happened because the user had installed too low a rating fuses in the power supply and too high a rating slow blow speaker fuses.  Thus an overload blew the internal fuses instead of the speaker fuse.  New fuses of correct value, a few hours slow run up on a variable AC power supply, and the amp still runs like new, 30 years later.

Musically both units still come close to our best new equipment.  They were designed right in the first place.

We really build durable equipment and still service most everything we have ever built.

Frank

dB Cooper

Re: Old AVA equipment revisited
« Reply #1 on: 4 Oct 2018, 01:38 am »
Great gear as anyone who has ever owned any will attest

Tone Depth

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Re: Old AVA equipment revisited
« Reply #2 on: 4 Oct 2018, 05:00 am »
The discrete Transcendence Two was the last iteration in my PAT 5 Preamp chassis, before moving to the AVA chassis with Omega III/Insight+ EC upgrades. Frank, are you saying that the Omega and Insight+ designs weren't significant successive improvements over the discrete Transcendence Two?

yeldarb

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Re: Old AVA equipment revisited
« Reply #3 on: 4 Oct 2018, 02:20 pm »
I wish you would post a "timeline" of your creations, with a short description of what they were, and any later mods from your company.

Tin_ear

Re: Old AVA equipment revisited
« Reply #4 on: 13 Oct 2018, 04:12 am »
What follows is a post in wrote on AK 3 1/2 years ago. It may provide a bit of info towards answering your question.

"There's not much info out there on this particular model, so I figured I'd take what sporadic info I gleaned elsewhere and condense it here for anyone who's curious.

Throughout the decade of the 80's, it appears to me the AVA PAT-5 evolved in the following order:
Super Fet (SS)
Fet Three (SS)
Fet Three Plus (SS)
Transcendence Series One (SS)
Transcendence Series Two (SS)  Mine is a 1986 incarnation
Transcendence Three Fet-Valve (Hybrid)

By 1990, within the all-SS models, the latest and best was the T2, and apparently very few were built, perhaps due to the upgrade costing over 1.5 times that of the next lower level upgrade (Fet Three Plus).

I've seen comments regarding PAT-4 and PAT-5 Super Fets, and they run the gamut, some not very complimentary. However, what few comments I found about the T2 were highly complimentary, so I figured I'd find out for myself.

Therefore, I recently found and bought an original owner PAT-5 Transcendence Two off the bay (still there in completed listings), and I'm very impressed with its performance. Its feature set is almost identical to the Mc C27 I recently owned, but can say pretty confidently I much prefer the presentation of the T2. Warm and smooth, yet detailed, whereas the Mc was warm to the point of a slight dulling of the presentation. Also, the T2's volume, and especially tone control steps are in smaller increments as well, for better control of the sound than the Mc.

The T2 preamp is part of my second system in the basement, and I enjoy it so much, I'm considering making a place for the system in my bedroom, where I can conduct more appropriate critical listening sessions. I'd really like to swap it out with the MX118 in my primary system and give it a good thrashing, but my wife is addicted to having a remote."

Well, that comparison never happened. No need, the MX118 proved to have a glare that kept me from listening as much as I did with the T2. Since we've moved, now the T2 and AVA Omega III 240 have been pulling duty driving a pair of Genesis IIs in the garage at the new house. That combo deserves a much better spot than in the garage, but I don't have a good spot for them in the house currently.

I wouldn't remotely think about selling them (everyone does have a price, though), due to the paltry going rate. I highly doubt I'd find anything with the sound quality and feature set (all the PAT-5 features are still active, including two phono inputs!, with disconnected low/high filters) these two provide, without spending considerably more.

Without trying to sound like I'm speaking for Frank, when he and I talked about me sending in my T2 for any kind of upgrade/improvements, the only thing they could do was to install modern lower-distortion current buffer ICs, making the T2 comparable to the current SS offering. I ultimately decided the slight improvement wouldn't have been worth the cost.
« Last Edit: 15 Oct 2018, 01:07 am by Tin_ear »

Tin_ear

Re: Old AVA equipment revisited
« Reply #5 on: 15 Oct 2018, 02:31 am »
My last post rekindled my interest in hearing this gear in a proper setting, not crammed onto a shelf in the garage, only playing as background music. Therefore, between commercials, half-times, and innings, today I gathered the following pieces into a "dining room vintage system."

Recapped Sherwood S-2400 tuner - 1974
Refoamed Bose 601 Series II - 1984
Dynaco PAT-5, AVA Transcendence Two - 1986
Dynaco ST-150, AVA Omega III 240 - 1997 (it is 20-plus years old, so it may be vintage by now)





Only having just connected the electronics to the Bose for the first time today, I haven't been able to give the system a good audition, since my wife's been in bed sick all day. However, at first blush using FM, I immediately noticed the broad soundstage that the "Direct/Reflecting" Bose models are known for. Previously the 601 IIs were stuffed into a corner under the TV in the living room, so their special characteristics had not been on display. I will post more when I have more time (home alone) to give the system a good audition, including CD and a turntable or two.

avahifi

Re: Old AVA equipment revisited
« Reply #6 on: 15 Oct 2018, 02:57 pm »
The Transcendence Two was a very special preamp design, using matched Fet input circuits and matched bipolar drivers, followed by unity gain current buffer output circuits.  It can be improved with much lower distortion current buffers, but it is a tedious job to replace these parts.  It requires fitting a 5 pin surface mount LME49600 current buffer in the board space of a 10 pin thru hole device.

It was discontinued when the dual fet input devices because unavailable.

I just bench tested one here, along with a Transcendence 2 solid state amp built in a Hafler 220 chassis. Both from 1988 production needing only a couple of fuses, a new preamp power switch, and jack, switch, and control cleaning with DeOxit D5 to put them back in great condition.

They are not as transparent or dynamic as our new products, but still better than most new stuff out there and they were built to last long term.

Frank

charmerci

Re: Old AVA equipment revisited
« Reply #7 on: 15 Oct 2018, 07:26 pm »
Having had many versions of AVA equipment over the years, FET3 pre-amp (I think), Transcendence, and now Synergy. I found the combination of the Omega III pre-amp, MOSFET-D amp in an old Dynaco ST-120 chassis to have been pretty amazing.
« Last Edit: 24 Oct 2018, 12:05 am by charmerci »