C-Audio amps - model history?

if i took a picture of the transformer would anyone be able to see? 

My name is Mihai Toma, a sound engineer from Timisoara, Romania.

I have in my hands a recently purchased RA501 which has started developing an intermittent problem on one of the channels. Would any of you have any schematic or service manual for the RA501, or would you have any idea where I could get them? I've combed what I think is the entire Internet for such a schematic, but have turned up empty until now.

Thanks in advance, and all the best!

I had found out about Mr. Basham on another forum, and posted in the appropriate thread - but I think that he's not into that forum, nowadays. But thanks to your info, I now have his Linea Research e-mail address, and will try contacting him directly. Thanks a BUNCH!

Mihai Toma

These have been bought used coming from a disco in 2002 for a bargain price.

Fans have been replaced because very noisy with sleeve bearing gone, with the original ETRI unit under thermal control circuitry and some checks have also been made here and there.

Ruggedness of the chassis is good, but the weight is quite high.

Four of them are currently driving four Nexo LS2000 subs with more than good result, lots of power and good control. Any channel drives a 18" woofer, 4 ohm load.

No thermal problems evere encountered with them.

The other two works usually in a biamplification rack 

One channel drives the LF section, the other channel of the same unit drives the HF section. Fx ranging from 80 to 1050 Hz due to the system combination used (under active digital controller).

Never had any problem with them, very reliable and good sounding, also with high energy program like compressed rock or tekno/house music.

These amplifiers are sturdily built and they were quite expensive.

Cool air is taken from the rear, where the fans are located, and it is exhausted from the front.

The can go warm but never absurdely hot also when pushed to the limit (clip led sparingky blinking) on 4 ohm load. Never used them on 2 ohm load.

Cooling system works well, despite the small holes in the front panel, but avoid to put them in cases with different amplifiers with opposite cooling direction, because heating problems may arise.

Also, do not use vented (perforated) blank panels in the front of the rack, otherwise hot air exhausted will degrade the cooling system efficiency, ricirculating on the back, especially in close spaces.

Regards

Marcello