How much better do they sound over stock, Mark?
How much better do they sound over stock, Mark?
Better, I couldn't give you percentagesThe thing is the standard output transistors have pretty low current gain & imho this loads the driver (which happens to be part of the voltage gain stage a little too much.
So I modified the amps to accept MJ11016 NPN darlingtons as output transistors, which have a current gain of about 1000 in the audio band. There appears to be less crossover distortion as a result. As the driver was more lightly loaded I decreased the value of the resistor that provides the class A power & again there was an improvement.
Think I'll have to change the op amps to something decent as they frankly deserve it. Only need six of them after all![]()
Bests, Mark
"We must believe in free will. We have no choice"Isaac Bashevis Singer
OPA627s are good!
I'll use OPAs, but i think the 134? Might be wrong on that score...
Just secured my third 405We now have (assuming all is well with this one) six channels of amplification
That's it, no more power amps needed... I have twenty (yes - 20) channels worth of power amps
Or if you like, four amps per channel with a 5.1 setupActive everywhere here I come...
Bests, Mark
"We must believe in free will. We have no choice"Isaac Bashevis Singer
Location: Yorks
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Bingo i won it, they are actually very thin on the ground & look unappealing to a lot but they are actually good sounding Turntables, keeps within the era i'm obsessed with aswellI'll fit either a Colton 'MC101' or Neat Corporation 'G30' tonearm with Goldring 'G800' cart.. providing it survives the post.
Leak 'Truespeed' £56.00
Last edited by Rare Bird; 04-04-2012 at 22:08.
Location: Yorks
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Ah yes! - I was trying to think of the arm identity. Too lazy to dig out my copy of 1971 Hi Fi Yearbook!
I assume the Truespeed is a 'floating' belt-drive design.
Are unipivot arms happy on these decks? I seem to rememember there was a fashion for fitting Hadcock unipivot arms onto the Linn LP12, so I guess they can work well together.
Barry
Location: Yorks
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