VISONIK V800HC rebuild /upgrade

[Jh8909 10+ year member]

cool, glad to see there is progress getting made everyday.

 

[amprepairman 10+ year member]

today's work

 

[amprepairman 10+ year member]

today I got the amp basically back together..but there's still a lot to do. It now has new caps in the power supply..new fets that are all matched batch..new outputs in the bad channel that are match batched not only per part number but as a whole set..each channel now has all matching batch parts in it.and these are the exact replacement parts for this amp...they are SANKEN 2SC 3856/2SA1492 and as I think I mentioned before this amp also uses these same parts for drivers which is nice they are rated at 15 amps each at 180 volts and there are 12 per channel so its gonna take a little abuse to destroy them. We stuck with the original outputs for 2 reasons...1 there are not a bad part to begin with and 2 if you upgrade the outputs you have to replace all 24 of them along with 4 drivers so it really runs into some money as some of the high end outputs hit $15.00 to $20.00 a piece.I also spent several hours working on the board to help it out a bit..there is a close up pic of some of the solder work I did to it. the rail voltages are carried down both sides of the board from one end to the other by the traces closest to the amps side and what sometimes happens under a heavy load is you get a little voltage drop the farther away from the power supply that you get down toward the other end of the board- right on top of those traces on the other side of the board are the output transistors and the collector pin of each one is connected to the rail through the board so I applied heavy solder to both of them the whole length of the board.The reason I took the pic is that I wanted you to see that its not all chopped up and nasty looking and that's its one smooth flow all the way down the board. Lots of people believe its one of those"going to far" things but the mod is about sound quality- performance and reliability and my goal is to keep the rail voltage as consistent as possible all the way down the side of the amp.

With that I'm gonna have to stop working on it for a few days until I get the new op-amps in and I was missing 1 or 2 of the caps going into the audio stream and I will probably have to do some work on the power supply for the op amps supply voltage as my new op-amps will draw more current and I don't want there to be any problems with that later on....

 

[Jh8909 10+ year member]

nice work, so the new op-amps you had to order in?

 

[Jh8909 10+ year member]

any update today? or are the parts you need still in the mail?

 

[nphocus 10+ year member]

It's really nice to see someone that is passionate about amps. I look forward to sending my hypersound prototype to you one day... supposedly it's 1 of 12 ever made.

 

[O.G. D-Wet 10+ year member]

Where do you learn this kinda stuff??? I'd LOVE to have a small shop one day building/rebuilding amps and speakers and whatnot! Where can I get my self started?That would be AWESOME if I could get an apprenticeship somewhere!

 

[Shinju 10+ year member]

How much is all this costing?

I got a couple of MTX 225HO's that I would love to get back in working order again.

 

[chardy85 10+ year member]

How much is all this costing?
I got a couple of MTX 225HO's that I would love to get back in working order again.

He is super busy most of the time. I do not know how often he will check this thread unless he is updating it.

You may want to shoot him an email. ifixamps@yahoo.com

 

[bubbagumper6 5,000+ posts]

I'd really like to follow this but your updates are horrible on the eyes...it's just a giant wall of text

 

[Jh8909 10+ year member]

Its worth the read IMO. but however it is my amp lol. and as for a mini update right now he is just still waiting on parts to come in.

 

[Jh8909 10+ year member]

How much is all this costing?
I got a couple of MTX 225HO's that I would love to get back in working order again.

ill pm you

 

[Jh8909 10+ year member]

How much is all this costing?
I got a couple of MTX 225HO's that I would love to get back in working order again.

ill pm you

 

[Jh8909 10+ year member]

Where do you learn this kinda stuff??? I'd LOVE to have a small shop one day building/rebuilding amps and speakers and whatnot! Where can I get my self started?That would be AWESOME if I could get an apprenticeship somewhere!

you in maple shade? my cousin lives on w center ave

 

[Jh8909 10+ year member]

Where do you learn this kinda stuff??? I'd LOVE to have a small shop one day building/rebuilding amps and speakers and whatnot! Where can I get my self started?That would be AWESOME if I could get an apprenticeship somewhere!

you in maple shade? my cousin lives on w center ave