Will an AD843 or OPA637/627 drop in for an NE5534 AN and if so, which version do I want. The NE chip is in 8-DIP package, and I believe I found some of the other chips in that package, but seemed like a lot of different versions were available from Digikey. Also the NE chip has a ceramic type compensation capacitor, do I need to remove that, or is it still needed.
Another quick question, I'm upgrading a Musical Fidelity Phonostage, the X-LP. I was planning on upgrading the power supply caps with panasonic types instead of the TEAPO's that are in it, does that make sense? Also some of the resistors, 4 to be exact, located near the opamp in the first gain stage and the SSM2210 in the second gain stage, have Ferrite beads acting like standoffs on them, why would this be?
How do you read film caps that have something like 104j and then 250v. I assume the 250v is the voltage rating, but what does the 104j mean. Thanks.
Another quick question, I'm upgrading a Musical Fidelity Phonostage, the X-LP. I was planning on upgrading the power supply caps with panasonic types instead of the TEAPO's that are in it, does that make sense? Also some of the resistors, 4 to be exact, located near the opamp in the first gain stage and the SSM2210 in the second gain stage, have Ferrite beads acting like standoffs on them, why would this be?
How do you read film caps that have something like 104j and then 250v. I assume the 250v is the voltage rating, but what does the 104j mean. Thanks.
AD843 or OPA627 should be OK if pin 1 (used for offset adjust) is not connected to your NE5534 socket. The ceramic cap should be connected between pins 5 and 8 and can be left in if so connected, pin 5 on AD843 and pin 8 on OPA627 is NC.
If the NE5534 is in this X-LP phono stage then you should use the OPA627, or OPA637 if the closed-loop gain is =>5 at all frequencies. If this is a passive RIAA phono amp then gain probably is >5, but the ceramic cap suggests unity gain compensation, so the OPA627 is the safe choice. The AD843 is about 10db noisier.
104j is 100000pF or 0.1uF, 5%.
If the NE5534 is in this X-LP phono stage then you should use the OPA627, or OPA637 if the closed-loop gain is =>5 at all frequencies. If this is a passive RIAA phono amp then gain probably is >5, but the ceramic cap suggests unity gain compensation, so the OPA627 is the safe choice. The AD843 is about 10db noisier.
104j is 100000pF or 0.1uF, 5%.
Thank you for the help. I will take your advice and go with the OPA627 then.
I'm replacing what I believe to be polyester capacitors. I can get relcap RTE's for some of the values, but not most. I need a 33pf, 22pf, 3300pf, 8200pf, 1200pf, and a .1uf cap. I was thinking of using Silver Mica caps, are they any good? What about polystyrene's? What about the RTE's for the 1200, 3300, 8200, and .1uf's?
One last thing, I decided to upgrade the power supply caps, which were 470uf at 35v with Panasonic FC 660uf's at 35v. They are the same diameter but taller, which I think should not be a problem. Does anyone see any other problem I didn't think of? Thanks.
I'm replacing what I believe to be polyester capacitors. I can get relcap RTE's for some of the values, but not most. I need a 33pf, 22pf, 3300pf, 8200pf, 1200pf, and a .1uf cap. I was thinking of using Silver Mica caps, are they any good? What about polystyrene's? What about the RTE's for the 1200, 3300, 8200, and .1uf's?
One last thing, I decided to upgrade the power supply caps, which were 470uf at 35v with Panasonic FC 660uf's at 35v. They are the same diameter but taller, which I think should not be a problem. Does anyone see any other problem I didn't think of? Thanks.
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