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Phono Preamp IC

Started by Marcos, July 02, 2005, 02:06:40 PM

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What is the best choice for a MM cartridge 4 mV output, 1 or 1,5 Kohms internal resistance? An LT1115, OPA134, OPA637?


Sigurd Ruschkowski

Depends on the design.
Do you have a schematics?


Sigurd Ruschkowski

!Ola! Marcos

The link to LT is not working for me,
but all the other links are OK.

I have bought two PCBs of the Bugle. Great looking PCB!
I have not installed any components yet. I do have most
of the OPamps I will try for the Bugle:
OPA627B (by using Brown Dog's adapater PCB)
Maybe the OPA745 or 743 as input OPamp.
Maybe the 8610?

I would try the same OPamps for the CM phono amps.

Even as important as the OPamps are the capacitors! Use the best you can afford. Polypropylene or polystyrene.

The Bugle PCB only has one power supply for both channels which I do not like. Use two separate PS if you can.

Sigurd - a high end audio person


Hi Sigurd!

The LT correct link,C1,C1154,C1009,C1026,P1293

Do you use one transformer for each channel?


Sigurd Ruschkowski

Quote from: MarcosHi Sigurd!
Do you use one transformer for each channel?

Always. For power amps and for other amps.

My latest line amp prototype power supply uses 200VA transformers for each channel, and each channel even has its own AC line filter.

On the LT schematics I would change the buffer to a 634 buffer instead.