Is Acrosound T-330 really good?

[pchw]

I came across an auction of a NOS T-330 in ebay. It ended at over $400. Can someone educate me why it is considered this good for such a price?

Thanks,

[SY]

Because it's rare and desirable for collectors. It's very good iron, but no better (and in many respects not as good) as something that can be bought new for less than half that price. But the object itself is a piece of history, so it has worth to many beyond the question of its actual performance.

[kevinkr]

I've built amplifiers around the Acro TO-330 (and TO-300 which I preferred) which imo should only be used exactly as intended - in UL connection. The leakage inductance is not as low as you would expect and it is a lousy performer in triode connection - which is what I preferred by that point in time. (Poor HF bandwidth)

SY is right, there are definitely better transformers out there, and probably for a little less money.

[pchw]

Hi Kevin, Sy,

Excellent comment. I am for the performance not the collectors value :-)
I have a pair of Eico HF-52's which is essentially integrated HF-50
with a sucky preamp section. I am thinking about to restore them as 2 HF-50 monoblocks which are pretty much the same as the bigger brother HF-60 with the exception of the T-330 OPT's. That's the reason why I asked the question because looking at the ebay prices, the HF-60 going price is consistently 250+ above the HF-50 which kind of puzzling me how much the Acrosound is better than the Chicago iron.
Just to get a feel of how modern iron compare to these classics, how close is Edcor CXPP60-MS-4.2K to the T-330 in performance? Maybe I should really ditch the old Eico's and build a completely new pair of monoblocks.

[Bandersnatch]

hey-Hey!!!,
The Chicago iron in the HF50 is better than the TO-330. IIRC it's number goes 322007. I've seen folks making nice stuff with the 330, example being DejaVu audio's PP 45 amps around that transformer. In my own testing the 330 was definately second rate, even with circuits it is supposedly 'made for'. I abandoned the idea of taking it apart to make copies of it.
cheers,
Douglas

[kevinkr]

Originally posted by pchw
Hi Kevin, Sy,

Excellent comment. I am for the performance not the collectors value :-)
I have a pair of Eico HF-52's which is essentially integrated HF-50
with a sucky preamp section. I am thinking about to restore them as 2 HF-50 monoblocks which are pretty much the same as the bigger brother HF-60 with the exception of the T-330 OPT's. That's the reason why I asked the question because looking at the ebay prices, the HF-60 going price is consistently 250+ above the HF-50 which kind of puzzling me how much the Acrosound is better than the Chicago iron.
Just to get a feel of how modern iron compare to these classics, how close is Edcor CXPP60-MS-4.2K to the T-330 in performance? Maybe I should really ditch the old Eico's and build a completely new pair of monoblocks.

Originally posted by Bandersnatch
hey-Hey!!!,
The Chicago iron in the HF50 is better than the TO-330. IIRC it's number goes 322007. I've seen folks making nice stuff with the 330, example being DejaVu audio's PP 45 amps around that transformer. In my own testing the 330 was definately second rate, even with circuits it is supposedly 'made for'. I abandoned the idea of taking it apart to make copies of it.
cheers,
Douglas

Keep those old eico output transformers, they really do perform well, and I thought just a bit better in most situations than the TO-330 in the HF-60. You could do far worse than just to make your HF-52s into a pair of stock Eico HF-50 - this was certainly one of the very best amplifiers of its era, and with modern parts is bettered by very few in my experience.

[pchw]

Wow, this is a prime example of perception vs reality!!!
You guys really open my eyes. Otherwise, I wouldn't know the T-330's are over-hyped in terms of "price performance) and the Chicago irons are quite good even by the veteran's standard.

Douglas, did you mean 32007? The OPT has this parts number etched in the case.

[Bandersnatch]

Originally posted by pchw
Douglas, did you mean 32007? The OPT has this parts number etched in the case.

hey-Hey!!!,
I suppose I did. I guess that time added another '2' to that file... I've got that one on my list of outputs to unwind and examine. I think every one of those HF50's I've seen came with really early tubes; xf1 EL34 and metal based GZ34...sweet!
cheers,
Douglas

[pchw]

Originally posted by Bandersnatch


I think every one of those HF50's I've seen came with really early tubes; xf1 EL34 and metal based GZ34...sweet!
cheers,
Douglas

LOL, one of the HF-52's came with those Mullard EL34. I thought I got a treasure. It turned out hey barely moved the meter of the tube tester. I never saw any tube weaker than that :-)

[Bandersnatch]

hey-Hey!!!,
I guess I got lucky then. All mine tested like a new valve. IIRC I got $1k1 for those amps and tubes back in '01. Man-oh-man did I ever need the money. I do wish I had the outputs now, I'd be unwinding them to discover how they were made and to make more. I think I know where a single '52 is though...
cheers,
Douglas