?Early GAT preamps

[medwardo]

I've been looking to upgrade from my ET5 on the main rig to a GAT S1.

There are a few GAT S1s for sale out there. Some are very early (e.g., 10 of 250) and some are mid range (125 of 250). (Not considering buy an S2 due to cost.)

Were there changes along the way as they built out the GAT range? That is, any reason not to buy an early build?

I'll get it updated to a S2 anyway, but just curious if anyone has thoughts/experience about early vs. later builds of the S1s.

Thanks!
ed

[Puma Cat]

Its a GAT, so...I think you have all the info you need.

I would very highly doubt that there any differences whatsoever between a lower SN and a higher number SN Series 1 GAT. That is simply not how production works. Any specific model has a set of engineering and parts specifications, and a BOM (Bill of Materials). Once you put a given model into "production" you want virtually all of them to be identical with respect to their engineering specification and BOM so that all customers can expect the same level of functionality and quality. The only reason an engineering change within a given series would be required would be due to a safety risk, regulatory compliance change, or a failure mode that was discovered post-launch that put the unit or end-user at some safety risk or failure to meet specification. This would be documented as part of the company's QA documentation as an ECO, or Engineering Change Order, and would likely result in a product recall. A good example would be the problems that Schiit encountered with the recent launch of the Sol turntable.

The Series 2 designation is where C-J made a specified change that resulted in a change in the GAT model range with respect to design, functionality, and possibly BOM that distinguishes that Series 2 from Series 1. This way C-J knows how to provide service and support units within each specific series.

Even the GAT S1 is arguably one of the best preamps ever built by anyone, ever...

[medwardo]

Thanks, Puma Cat!

[microstrip]

Although changes during a model life can happen with some other brands, conrad johnson models are very consistent along their life - I would expect GAT sn 1 to be exactly the same as the last GAT produced before the GAT 2.

I have had two Premier 14's, one early sample and a late one side by side - the only way to separate them was looking at the serial number.

The GAT2 has a different printed circuit board than the original GAT (series 1) . During the upgrade the old most expensive components are migrated to the new PCB, six new very expensive Teflon capacitors are added, as well as new power supply regulators and a few components. IMHO the upgrade price in the US is a real bargain considering the new parts and work involved in the operation.

[Puma Cat]

Originally Posted by microstrip

... six new very expensive Teflon capacitors are added, as well as new power supply regulators and a few components...

Urg....I wouldn't want to have to burn-in six new Teflon caps. Yeesh.

[keef]

I know one thing, I noticed a huge difference when my ET5 finally burned in. Outlasted the factory EH tube, took forever. BTW, it was only when I inserted a Siemens that I started getting longevity. Might talk to CJ about that at CAF this weekend uhummm.

[medwardo]

Thanks, Microstrip! Yea, I'll get it upgraded in a bit to a S2. Good to know that early units are no different from later production units in the same series.

I have an ET5 that I bought new and it took forever and ever to break in...months as I recall. Once it did, wow...especially with a bit o' tube rolling.

The ET5 is hard on tubes, just like its little brother, the ET3SE in my office system.

6922 Type 3s last awhile, as do Phillips Miniwatt E88CCs. (6 months to a year before degradation is noticable; the latter is an awesome tube in the ET5!) CJ sourced 6922s are usually (pretty) quiet, but they don't last as long in my experience and they sound thin to my ear.

I'm not terribly excited about having two tubes to deal with now instead of one, but I'm excited enough about the potential of the GAT that I'll deal.

[Puma Cat]

Originally Posted by medwardo

Thanks, Microstrip! Yea, I'll get it upgraded in a bit to a S2. Good to know that early units are no different from later production units in the same series.

I have an ET5 that I bought new and it took forever and ever to break in...months as I recall. Once it did, wow...especially with a bit o' tube rolling.

The ET5 is hard on tubes, just like its little brother, the ET3SE in my office system.

6922 Type 3s last awhile, as do Phillips Miniwatt E88CCs. (6 months to a year before degradation is noticable; the latter is an awesome tube in the ET5!) CJ sourced 6922s are usually (pretty) quiet, but they don't last as long in my experience and they sound thin to my ear.

I'm not terribly excited about having two tubes to deal with now instead of one, but I'm excited enough about the potential of the GAT that I'll deal.

Yeah, those E-H 6922s are a bit thin-sounding. I'm using Ediswans for my LP70S input stage.

[medwardo]

GAT arrived and it's everything that I've read/heard about.

Staying up too late again...hard to pull myself away from the music. Simply the best my system has ever sounded.

Thanks to everyone...your posts helped me make an informed decision.

FWIW, I put in a pair of EAT E88CC/6922 tubes in the GAT. I've had these tubes for awhile now and stopped using them in the ET3SE & ET5 due to noise (rush)...in the GAT, these tubes are virtually silent. Odd.

[Puma Cat]

Congrats!

Glad to hear the GAT is working out; I guess there is a reason many feel this is one of the best preamps ever made. I had my eye on that specific GAT S1 for a while, too. I seriously considered buying it, so I am glad it went to someone at AA.

Enjoy and keep us appraised as you get more experiences with it.