Just got a Pyle PYP-X1 preamp for next to nothing, solid build, looks good but the sound could be a lot better.
Dont really want to spend a lot of cash squeezing juice out of a rock but what do you think guys, is it worth changing a few caps, upping the power supply caps, etc? Im open for suggestions other than using it as a door stop.
Gil
Dont really want to spend a lot of cash squeezing juice out of a rock but what do you think guys, is it worth changing a few caps, upping the power supply caps, etc? Im open for suggestions other than using it as a door stop.
Gil
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The ones in the pre are BA4558. And that would be a direct replacement with nothing to alter?
Yes I agree with Tekko. OPA2134's are good and cheap, and are pin compatible with your 4558's. I have done this in many amps and CD-players and the sound improvement is enormous!
It should work fine without extra components, but if you want to be super-safe, you could add a small cap of 100pF between pin 1 and 2, another 100pF between pin 6 and 7, and a film-cap (MKT, MKP or similar) of 10nF between pin 4 and 8 (power supply pins), on each of the OPA2134.
Another modification that improves sound quality quite a bunch is to parallel all those electrolytic capcacitors with film-caps of 10% of the value (100nF - 1uF). This goes for both those that are in the power supply and those that carries the actual audio-signal. The easiest is to solder these caps to the pins of the original caps on the underside of the board.
Have fun, and on't forget to reply with images and your listening impresions 😀
It should work fine without extra components, but if you want to be super-safe, you could add a small cap of 100pF between pin 1 and 2, another 100pF between pin 6 and 7, and a film-cap (MKT, MKP or similar) of 10nF between pin 4 and 8 (power supply pins), on each of the OPA2134.
Another modification that improves sound quality quite a bunch is to parallel all those electrolytic capcacitors with film-caps of 10% of the value (100nF - 1uF). This goes for both those that are in the power supply and those that carries the actual audio-signal. The easiest is to solder these caps to the pins of the original caps on the underside of the board.
Have fun, and on't forget to reply with images and your listening impresions 😀
Bypass them for the sake of sound quality.
Replace them if they are malfunctioning.
...some might say you should replace them anyway, but in my opinion it would be a bit too much. Your call.
I dont know if I'd immediately recommend OPA2134, i'd want to see what kind of local decoupling there is. 100nF on pins 4 and 8 to ground close to the chip is pretty much mandatory for OPA2134. NE5532 would be a good start.
I'd say for this pre-amp, NE5532's are probably the best bet. I am assuming here of course that the input and outputs are capacitively coupled - but, if this is a 4558 op-amp based circuit, then this is pretty much mandatory, so you should be good to go.
Ok so, either OPA2134 or NE5532 would be a straight replacement with nothing to alter? And yes this is a 4558 op-amp based preamp.
OPA2134 wont be worth it as these are much faster opamps - they will probably just oscillate. Unless you're planning to go further eg rebuild the power supply etc, there is no point. Stick to the NE5532. Yeah they are "old" opamps now but they are still very good quality especially for the price.
NE5532 aint much better than the 4558, high noise, high THD etc.
I generally use OPA2134 or better. TL074 and such only gets used in subwoofer related circuits or other dc/low freq.
I generally use OPA2134 or better. TL074 and such only gets used in subwoofer related circuits or other dc/low freq.
Changed the opamps to OPA2134 and right away the sound became "softer" and more detailed, this preamp in its original version had a very hard fatiguing sound, it is still in your face kind of sound but its tolerable now and not fatiguing to listen after a while. Also beefed up the power supply caps, Im wondering if changing diodes with schottky's would help any?
"NE5532 aint much better than the 4558, high noise, high THD etc."
I am afraid you are wrong on that Tekko. The 5532 is a great op-amp for audio and its cheap.
I am afraid you are wrong on that Tekko. The 5532 is a great op-amp for audio and its cheap.
Compared to OPA2134 and the ultralow THD and noise opamps from National semi, NE5532 is a piece of junk opamp in my opinion.
Either you have a few things to learn my friend, or you are just being plain obnoxious.
In any event, I wish you a pleasant day.
In any event, I wish you a pleasant day.
..... hm...lets see .... adding supreme op amps in a machine that has no tone control bypass switch doesnt acually make real sense
i presume that the benefit of a good op amp will be consumed by the limitations of the tone control
then again upgrading a machine that has such a terible inputy selection and presumambly terible crosstalk figures either from left to right or if more than one active source is conected to it is absolutelly pointless to my understanding ...
either you simply replace the chips and keep it as absolutelly is and may add a few better caps in the power supply where the diference will be bearly audible
or remove the guts from it since its quiet roomy install inside a decent line stage skip the tone control and use a shunt topology relay stack for input selector...this will end up to good hiend machine ...
edit : forgot also the pot hat needs to be replaced
this is how i see it
Regards sakis
i presume that the benefit of a good op amp will be consumed by the limitations of the tone control
then again upgrading a machine that has such a terible inputy selection and presumambly terible crosstalk figures either from left to right or if more than one active source is conected to it is absolutelly pointless to my understanding ...
either you simply replace the chips and keep it as absolutelly is and may add a few better caps in the power supply where the diference will be bearly audible
or remove the guts from it since its quiet roomy install inside a decent line stage skip the tone control and use a shunt topology relay stack for input selector...this will end up to good hiend machine ...
edit : forgot also the pot hat needs to be replaced
this is how i see it
Regards sakis
Of course Sakis, the best thing to do would be be to do as you say.
However, why spend a lot of money on an OP2134 on this? A 5532 will definitely improve the sound and it costs 50c.
However, why spend a lot of money on an OP2134 on this? A 5532 will definitely improve the sound and it costs 50c.
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