Linsley Hood 75W Amplifier

[DrStrangelove]

After all these years it's failed me on one channel.

I suppose I'll have to get a round tuit.

But first I'll have to find the Powertran build instructions that are "here somewhere or other" in one or other of the piles of paper.

It's not the one in the Powertran case but a second one that I built in a RS case with very large heatsinks on the back.

Ho hum.

The last time it went wrong it was the curse of the Red Tants (100uF 10V gone open) after which it went downhill rapidly with the wind behind it.

[Craig]

I'm fairly sure that back at age 16 I invested in a Powertran kit. The TO3 power transistors were towards the top back of the case - I think on insulating washers. Worked absolutely fine until I put the lid on. The internal flange on the back of the lid shorted all the power transistors to ground. I was gutted - and then angry - it was clearly a design error absolutely guaranteed to blow the amp up.

And Powertran (if it was them) walked smartly away. Did not even have the grace to reply to my letter.

Craig

[DrStrangelove]

Haven't found the round tuit for this, so dug out my late father's Aiwa NSX-V30 music centre thing.

The CD player is toast so I feed it from a Sanyo portable via the aux input.

Sounds remarkably all right with all the ridiculous bass extension turned off and the vents on the speakers blocked to turn them into infinite baffle & thus reduce the bass a bit more.

[DrStrangelove]

Tried it with a pair of Mission speakers: didn't like the impedance & turned itself off in protest.

Worked ok with a pair of Spendor BC2s, though far too bright for my taste.

Might have to hang something in front of the tweeters.

Bits of "Assault and Battery/The Golden Void" by Hawkwind were even more eyewatering than usual.