I was very lucky getting a Valkyrie Line state preamp very cheap
The preamp came in the early 90S, it uses a combination of op amps AD744JN, AD811N, AD712JN.
Sounds really good the way it is, but I always like more performance
Here are the schematics
https://studylib.net/doc/8685097/valkyrie--a-line-stage-preamplifier.
Any recommendations ?
The preamp came in the early 90S, it uses a combination of op amps AD744JN, AD811N, AD712JN.
Sounds really good the way it is, but I always like more performance
Here are the schematics
https://studylib.net/doc/8685097/valkyrie--a-line-stage-preamplifier.
Any recommendations ?
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Unless you have tube sources, the volume and balance controls can be much lower in value, 10k is fine.
They may need replacement by now, anyway.
They may need replacement by now, anyway.
Yeah, leave it as is, a number of the amplifier stages are composite types (i.e. two op-amps in the primary feedback loop) and the AD744 has a nonstandard pin out. Fiddle around with swapping op-amps and you could end up with an oscillator.
I would replace the ALPS posts perhaps with Khozmo, TKD or Mr. K stepped attenuators as the only significant update. The Alps as a former fan are not that great. Maybe use mono attenuators, one per channel (one in place of balance control.)
I would replace the ALPS posts perhaps with Khozmo, TKD or Mr. K stepped attenuators as the only significant update. The Alps as a former fan are not that great. Maybe use mono attenuators, one per channel (one in place of balance control.)
