Rotel RIAA Module

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Hi,

I'm the owner of a Rotel RC-03 preamplifier, made in 2003.
While cleaning the pots, I noticed it has a socketed RIAA module which made me wonder if there was any room for improvement.
IMG_5760.jpg


I searched the net for a service manual for the RC-03 but couldn't find one. Then I found out that the same module was used in a whole range of preamps of that era, like the RC-1070 of which I also found a manual.

Here is a photo of the module:

ROTEL RC-03 RIAA.jpg



and the schematics:

ROTEL RIAA 1.jpg


I want to know if I could replace the NE5534 with something more modern.
I read nice things about the OPA827. Is it a good choice?
Could I swap the NE5534 with the new one by just adding some 0.1μF caps from positive and negative to ground (as stated in the manual of the OPA827) or should I make any other change to the circuit as well?

Thank you very much!
 
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Thank you both.
Merlin el mago the 4.7μF PP are really huge capacitors. I don't know if they can be mounted in the same place but I will try. If you take a look at photo # 1 they are the ones next to the jumpers


Also MKS2 4,7µF/50V will be a possibilty. Not so big in size and with a pin spacing of 5mm available. Still better than the electrolytics.


BR
Günni
 
I didn't argue , that they will beat all electrolytics. There will be a sonic improvement against the orginal equipped one and longterm stability will also be improved. A further improvement may be replacing the 1206 resistors with Mini-melf resistors, as suzyj showed in her investigations (better THD).


@ merlin el mago
The lowest voltage available is 50V and the maximum capacity is 10µF with pin spacing of 5mm (acc. https://www.wima.de/wp-content/uploads/media/e_WIMA_MKS_2.pdf).
 
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Is there any particular reason why nobody has pointed out the main shortcomings of this circuit yet?
1. Input impedance is nonstandard, at ~68k || 250p. Check requirements of cartridge used and capacitance of existing cabling. This might work well with a Shure M97xE but most any AT cartridge is going to be a bit unhappy.
2. Feedback network impedance has been kept high so that capacitor values could remain small. Noise levels thus are, in all likelihood, not as low as they could be. (A 2k2 series resistor in the input CRC filter is not helping matters either.) The OPA827 may help a bit but I wouldn't expect a night and day difference either. Improving upon an NE5534 (especially 5534A) in a phono pre application is not a trivial task.
 
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