Finished my Brian GT LM4780s

[Russ White]

Here it is folks. Nothing special to look at. I did not want to spend too much time on an enclosure until I knew how it sounded. There will be a nicer one to follow.

Well I can safely say I am blown away. This amp sounds far better than my $2,000 Denon.

Here are the specs:

1 400VA toroid trafo with 21V dual secondaries.
2 parraleled LM4780 amp PCBs from Brian.
Both rails are fused at 6 amps fast blow.
The mains are fused with a 3 amp slow blow.

I put a very quite ball bearing 12V fan on the side with a vent on the other. This thing runs nice and cool.

To power the blue LED and fan I wound 18 turns of black hookup wire around the toroid which got me about 5.5V.

This thing just sounds way too good. No hum at all. Gain may be a little high, I may adjust it.

Here are some tips:

1) The LM4780 is not isolated so make sure you use an isolator. I learned tis this hard way (thanks for helping me out Brian!)
2) Brians Kit so rocks. Get one, or a few if you have a surround reciever with pre-outs.
3) Prepare to be astounded.
4) Grab a good brew, Antlic Brewing Company's "Coal Porter" makes listening to a new amp even better.

[BrianGT]

Pictures not coming through properly, here are fixed links:






It will be nice to see how the "big cap" kit works out for you once I get the boards.

--
Brian

[G4ME]

Looks good, you have more information on the cap upgrade, and where did you score the transformer?

Although, I prefer a nice Shipyard, but alas brewing is my day job to fund my audio adventures.

[Russ White]

Retrying images....

[Russ White]

Thanks.

I am going to be build another dual mono amp using Brian's snubberized PS board and the LM4780 amp PCBs. I will compare the two (regular PS vs "Big Cap") side by side.,

For now I see the standard PS version will be stiff competition. It is very detailed, with plenty of bass punch. My wife was just amazed. She couldn't stop saying "That little chip is doing all that?" I had to grin.

I have not had the pleasure of trying "Shipyard" but I will certainly try to rectify that! I am not sure I can get it in Nashville though. I hope I can!

The trafo I got from "Antek" who deals on ebay. His trafos are very nice. He even has some really good high voltage trafos for the tube guys.

One other note - I only used one of the rectifier boards for the two amps. The other I used for the third secondary (my own) so I could use the DC fan and the blue LED.

[Russ White]

Funny thing. My brother in law was visiting and brought me 6 cases of beer. In amongst them is some "shipyard".

I didn't even make the connection until now.

But I have some "Bluefin" and "Prelude".

[Upupa Epops]

To Rus : What is your age ?

[G4ME]

nice i will look into that guy on ebay see what he has for my 3886 when i start the plung.

I was going to say, you can find atlantic brews in TN but no Shiypard? odd, atlantic is a pretty small micro brew up the coast, where shipyard is the third largest in New England. But if you had someone bring them down to you then it makes more sense.

Looks like you are a fan of the Stouts and Porters, so am I, i can't get enough of them. Prelude is personally my favorite, it drinks like a meal and sticks with you. Sadly its a seasonal and not offered year round.

Enjoy the Brews, and let us know how the snubber compeats with the standard PS

[Alcaid]

Antek on ebay is really John Ango who is behind par-metal. I have ordered from him a couple of times. Still waiting for my last order (a 2x21V 400VA toroid and a cabinet for my amp). Waiting for an international shipment really sucks when you can't afford expensive shipping methods.....

[Russ White]

Upopa, I am 35. jeez I am old!