Phono Preamp IC

[Marcos]

Hi

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

Marcos.

[Sigurd Ruschkowski]

Depends on the design.
Do you have a schematics?




Sigurd

[Marcos]

Hi!

The schematics may be
http://www.linear.com/pc/productDetail.donavId=H0,C1,C1154,C1009,C1026,P1293

http://www.hagtech.com/images/bugleschem.gif

http://www.geocities.com/fabiomauriciotimi/cm203.gif

CM203 components in
http://www.geocities.com/fabiomauriciotimi/cm203.htm

http://www.geocities.com/fabiomauriciotimi/cm204.png

CM204 components in
http://www.geocities.com/fabiomauriciotimi/cm204.htm

Marcos.

[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:
OPA2134
OPA627B (by using Brown Dog's adapater PCB)
Maybe the OPA745 or 743 as input OPamp.
Maybe the 8610?
8065?

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

[Marcos]

Hi Sigurd!

The LT correct link
http://www.linear.com/pc/productDetail.do?navId=H0,C1,C1154,C1009,C1026,P1293

Do you use one transformer for each channel?

Marcos

[Sigurd Ruschkowski]

Hi Sigurd!
Do you use one transformer for each channel?
Marcos

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.


Sigurd