PL2000 Series 2

[Gepetto]

Try hard to NOT have any caps in the direct audio path.

3 rules to live by...

 

[e30m3mon]

We need a laughing face emoji in addition to the “like” button…too many gems out here that need proper recognition!

 

[Gepetto]

Those rules are like my other rules...

Check your test equipment first, it almost always is that which has you chasing your tail

And my rule that makes Lee laugh; Old Digital is just Old Digital...

 

[mlucitt]

If you MUST use an electrolytic in an audio path

Or a bipolar (BP) or nonpolarized (NP) electrolytic, or two electrolytic capacitors back to back, for example: negative to negative, then the two positive connections become the non-polarized version. Also, the capacitance divides in half, I believe.

Am I correct here, Joe? Then again, why would you do this if it violates Rule #3?

 

[Gepetto]

Or a bipolar (BP) or nonpolarized (NP) electrolytic, or two electrolytic capacitors back to back, for example: negative to negative, then the two positive connections become the non-polarized version. Also, the capacitance divides in half, I believe.

Am I correct here, Joe? Then again, why would you do this if it violates Rule #3?

Capacitance does divide in half. If you put 2 electrolytics back to back then be very sure to parallel with the film cap. Other than low ESR type caps (and those are not really very good either, they are just better) electrolytics do not have great high frequency characteristics.

That is one of the reasons that electrolytics are used in the output of many switching power supplies. The ESR of the electrolytic forms a zero in the feedback loop which is critical to the stability of the design.

 

[mlucitt]

And don't forget the first commandment of electronic safety:
(1) Beware of the lightning that lurks in an undischarged capacitor lest it cause thee to be bounced upon thy backside in a most ungainly manner.

 

[laatsch55]

I never make snarky comments, except where that cranky old oil man, Lee, is concerned.

Hey!!! Cranky???????????

 

[George S.]

Just ordered one of these "pmillett" sound card interface kits.
http://www.pmillett.com/ATEST.htm
Also ordered one of these reverse RIAA adapters.
https://www.ebay.com/itm/RIAA-Inver...-/173883445640?_trksid=p2349624.m46890.l49286
I want to look a little deeper into these preamps with better test equipment. I think the sound card interface will achieve repeatable, accurate results. The RIAA filter will be interesting to use with a frequency sweep to test the phono section.