And so Amplitude finished first 😉.
When I'm stuck, I often look at this Website > Kondensatorenwerte capacitors Mikrofarad Pikofarad Nanofarad Jukebox
Musikbox Wurlitzer Rock-Ola NSM Seeburg AMI Bergmann
When I'm stuck, I often look at this Website > Kondensatorenwerte capacitors Mikrofarad Pikofarad Nanofarad Jukebox
Musikbox Wurlitzer Rock-Ola NSM Seeburg AMI Bergmann
I can't tell from the picture, but values that low are most often C0G/NP0. The other dielectrics have pretty horrid voltage and temperature coefficients that using anything other than C0G/NP0 if the value you need is available in C0G/NP0 would border on incompetence. I can't think of any application where someone would take advantage of the nonlinearities of the cap. I also can't think of a situation where replacing a Y5V, X7R, etc. cap with a C0G/NP0 would degrade performance. That doesn't mean there isn't one - just that I can't think of one.
If you look at the other side of the cap, you might find a code that could lead you to the dielectric. It's typically two letters with a number in between.
Tom
If you look at the other side of the cap, you might find a code that could lead you to the dielectric. It's typically two letters with a number in between.
Tom
I figured the cap in the pic might be something like X7R or Z5U. If that's the case i'll replace them with C0G/NP0.
However could these in the pic already be NP0/C0G?
There's nothing on the other side to indicate what specific type they are.
However could these in the pic already be NP0/C0G?
There's nothing on the other side to indicate what specific type they are.
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Like Tom already wrote, values this low are almost never class 2 (X7R, X5R, Z5U and so on). It is very likely class 1, and nowadays almost all class 1 capacitors are NP0/C0G.
Well, the Manufacturer certainly knew what he used and what is needed there.
So trying to "improve" it at random is Russian Roulette.
So trying to "improve" it at random is Russian Roulette.
15, 20, 30 years ago anything from around 100pF upwards would not be C0G. What does the cap do in the circuit? You need to know that before even thinking about changing it.
It's for C1, C4, C6 on the boards of a Quad 909. I couldn't tell you what they do. I just know some are broken from an amp I received in transit.
It looks like a multilayer capacitor, so I guess it's NP0 anyway. 15 years ago is 2004, well after the introduction of multilayer caps. I've never seen class 1 multilayers in anything else than NP0/C0G.
330 pF single-layer capacitors from 30 years ago were usually something else, like N750 or N1500 (class 1, similar to NP0 but with a temperature coefficient of -750 or -1500 ppm/K) or even X7R (class 2, inaccurate and distorting). Single-layer capacitors were circular or rectangular and rather flat, and typically had a coloured band to indicate the dielectric type.
330 pF single-layer capacitors from 30 years ago were usually something else, like N750 or N1500 (class 1, similar to NP0 but with a temperature coefficient of -750 or -1500 ppm/K) or even X7R (class 2, inaccurate and distorting). Single-layer capacitors were circular or rectangular and rather flat, and typically had a coloured band to indicate the dielectric type.
Quad were know for using cheap parts, so I thought maybe they had used something such as X7R or Z5U for C1, C4, C7. I know for sure Quad used cheap and nasty MKT for the input coupling cap.
C1,4,6 are specified by Quad in the 606 model service manual as simply 330pF 50V ceramics as MarcelvdG describes. i.e the original, everyday, round disc type ceramic caps. The same C1,4,6 caps now fitted to the Chinese 909 products are obviously uprated to currently available 100V types. I would think that was necessary for availability/quality reasons.
Don't overthink the capacitors' role by imagining there could be problem where there is none or by fitting higher spec. caps, that there will automatically be sound quality improvements. Fit what is already proven to be more than satisfactory (i.e. simply a 100V ceramic type specified in the 909 service manual). I think you'll find, as others have said, that this will now be a COG/NPO multilayer type if bought now from a reputable distributor who also provides full specs and datasheet links for their products.
Don't overthink the capacitors' role by imagining there could be problem where there is none or by fitting higher spec. caps, that there will automatically be sound quality improvements. Fit what is already proven to be more than satisfactory (i.e. simply a 100V ceramic type specified in the 909 service manual). I think you'll find, as others have said, that this will now be a COG/NPO multilayer type if bought now from a reputable distributor who also provides full specs and datasheet links for their products.
Just emailed Quad and they said the part used was "UP125 type". Can anyone tell me what the hell is that lol?
Taiyo Yuden UP125-series. I can't find any specs for it.
What are you trying to do here? Are you looking to replace the cap? If so, just stuff 33 pF, NP0/C0G in there and be done. Alternatively, ask the manufacturer for a recommended replacement part.
Tom
What are you trying to do here? Are you looking to replace the cap? If so, just stuff 33 pF, NP0/C0G in there and be done. Alternatively, ask the manufacturer for a recommended replacement part.
Tom
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