Scott LK72 output transformer quality ?

[ashok]

Does anyone know how good the output transformer in the Scott LK 72 amp is.
I have a working unit that doesn't sound too great.
Can anyone with a revamped LK-72 comment about it's sound ?
I guess the caps must be dried up and resistor values gone South in my unit.
Thanks.
Cheers.

[Frank Berry]

I have an HH Scott 299-C amplifier. The LK-72 is the kit version of the same amplifier.
My amp sounds fantastic!
You can get massive amounts of data from this website:
www.hhscott.com.

[ashok]

Thanks Frank.
I will look at the web site. I do have the circuit diagram from an old Glass Audio magazine. My amp has the 7199 driver tube. The tube seem to be working OK - I can't say how good they are.
When I got it first and turned it on , the power tubes used to glow with a bluish light on the sides. I turned it off in less than 5 minutes after turning on. The bias was shot . Took a while to read up and find out what has to be done. Now it works but doesn't sound good. Just OK. My Hybrid tube/Mosfet amp sounds far better.
Maybe I will restore it and see how it sounds . After that I can decide if I should do a rebuild ( different circuit ) or not. I would however like to keep it as it is - provided it sounds good.
Thanks for the info.
Cheers.
Ashok.

[SHiFTY]

Blue glow is totally normal- its just the glass fluorescing.

Red glow from the large grey anode structure is whats dangerous.

Check and replace all coupling caps ( like 0.1uF 600V small caps) and old resistors and it will probably sound great.

[ashok]

Hi ShiFtY,
You are probably right. I should fix it.
The unit looks kind of beat up and the bottom looks like a maze with pp wiring . Something that I am not fond of. Yeah I know the purists insist that it is better.

It kind of looked daunting changing all the parts - that makes it many many beers away ! I looked at it again a while ago and decided that it was not so bad after all. A couple of hours every day should do it .

About the glow. I need to fix my aging brain. I forgot , it WAS a red glow. I remember reading that what happened was bad.
I did shut it off quickly and fixed it before turning it on again. Everything seemed to work after that. I just wondered if the tubes could have been shot being 'on' in that condition for about 5 or 10 minutes (max ). I can of course test the tubes.

It wasn't a very bright red , just a dull red which came on slowly and I shut it off as soon as I saw it.
Thanks.
Ashok.