Questions for the amp/pedal building geeks re: Caps

[StrummersOfThunder]

So I bought most of the electrolytic caps required for the recap on the re-201

I went to mouser to finish off the ordering and got into a very rabbity hole very quickly.

Ive also realised the jaycar brand is not well regarded in terms of bad caps , longevity etc...

Panasonic seems well regarded. But within panasonic there are many series and options.

So as far as electrolytic caps go for such an application:

What series available on mouser is appropriate? Im seeing things like FM, TA, MA, KS etc....
Do I need low ESR rated caps for any part of this ?

Cheers

[NippleWrestler]

Different series are typically for different spec requirements such as:

OPERATING TEMPERATURE RANGE (°C)
RATED VOLTAGE (V)
BODY DIAMETER (MM)
BODY LENGTH (MM)
CAPACITANCE (ΜF)
CAPACITANCE TOLERANCE (%)

According to Panasonic

Basically, any cap of a reputable brand that fits your requirements will do you just fine. You are right about Jaycar stuff though, it's inherently low quality, badly stored, and may have been there for a long long time, plus with how expensive it is it makes zero sense unless you're really in a pinch.

When I recapped my 1982 Boss BF2, the caps in there were total garbage anyway and not a reputable brand or anything else, just cheapy things that did the job. I replaced them all with JB brand capacitors and it's a much quieter unit.

[StrummersOfThunder]

Different series are typically for different spec requirements such as:

OPERATING TEMPERATURE RANGE (°C)
RATED VOLTAGE (V)
BODY DIAMETER (MM)
BODY LENGTH (MM)
CAPACITANCE (ΜF)
CAPACITANCE TOLERANCE (%)

According to Panasonic

Basically, any cap of a reputable brand that fits your requirements will do you just fine. You are right about Jaycar stuff though, it's inherently low quality, badly stored, and may have been there for a long long time, plus with how expensive it is it makes zero sense unless you're really in a pinch.

When I recapped my 1982 Boss BF2, the caps in there were total garbage anyway and not a reputable brand or anything else, just cheapy things that did the job. I replaced them all with JB brand capacitors and it's a much quieter unit.

So the operating voltage is different to the quoted cap voltage ?
Also how do I know the operating voltage for a specific circuit ?
The caps in the space echo are almost 50 yrs old and I’m told we’re not great to start with so they all need to go.
As you say, anything from a reputable brand is likely to be better than what’s in there.

[RectifiedAmps]

Are you replacing all the caps or just the electrolytics? Hopefully the latter!

Low ESR is only a consideration for power supply caps, where you want to filter out all hum n buzz. Usually vintage power supplies that are under-flitered (few caps or low uf values) benefit from most from low esr caps.

Voltage rating, uf values, and the construction (radial vs. axial) are usually the main considerations for me, then brand - but all brands are mass-manufactured and subject to similar quality control processes I bet, unless you go for the ridiculous cork-sniffer hifi stuff.

[StrummersOfThunder]

Are you replacing all the caps or just the electrolytics? Hopefully the latter!

Low ESR is only a consideration for power supply caps, where you want to filter out all hum n buzz. Usually vintage power supplies that are under-flitered (few caps or low uf values) benefit from most from low esr caps.

Voltage rating, uf values, and the construction (radial vs. axial) are usually the main considerations for me, then brand - but all brands are mass-manufactured and subject to similar quality control processes I bet, unless you go for the ridiculous cork-sniffer hifi stuff.

Just replacing the electrolytics

I think filtering out all hum possible would be ideal so should I pay up for low ESR caps in power section ?

Radial construction is a given as it’s all PC mount

Values in terms of printed voltage and capacitance I’m ok with determining but how do I determine the voltage rating I should be getting (there is a quoted range they differs per series )

[NippleWrestler]

Different series are typically for different spec requirements such as:

OPERATING TEMPERATURE RANGE (°C)
RATED VOLTAGE (V)
BODY DIAMETER (MM)
BODY LENGTH (MM)
CAPACITANCE (ΜF)
CAPACITANCE TOLERANCE (%)

According to Panasonic

Basically, any cap of a reputable brand that fits your requirements will do you just fine. You are right about Jaycar stuff though, it's inherently low quality, badly stored, and may have been there for a long long time, plus with how expensive it is it makes zero sense unless you're really in a pinch.

When I recapped my 1982 Boss BF2, the caps in there were total garbage anyway and not a reputable brand or anything else, just cheapy things that did the job. I replaced them all with JB brand capacitors and it's a much quieter unit.

So the operating voltage is different to the quoted cap voltage ?
Also how do I know the operating voltage for a specific circuit ?
The caps in the space echo are almost 50 yrs old and I’m told we’re not great to start with so they all need to go.
As you say, anything from a reputable brand is likely to be better than what’s in there.

The voltage rating for the cap is how much voltage it can take before it dies/explodes.

You know the voltage because you can measure it Or use your best common sense. A pedal with a 9v source isn't going to need 400v caps, and vice versa. But since you already have the old caps you can just source a like for like, however I always use caps at least twice the supply voltage (in my pedals at least) so a 9v supply requires at least an 18v cap. An 18v supply gets at least 36v (which isn't a thin but 35v or 50v would work) but that's because I need to account for the end user's 'interesting' approaches to powering pedals and sometimes people do plug the wrong thing into the wrong thing.

Anyway, quoted cap voltage is the max it'll comfortably handle. When I was in my BF2 I noticed they use some really small electrolytics around 0.22uf. Those I replaced with film caps of better quality.

[FuzzMonkey]

The service notes for the RE-201 should tell you the operating voltage. A rough rule of thumb is to use a capacitor that is rated at least double the voltage it will see in circuit. For example, if the voltage of a pedal is 18-volts you'd want caps rated at at least 25-volt or higher. 35-volt would be about right. The higher the voltage; the bigger the capacitor is size wise however.

Sometimes the biggest problem is finding the correct value and rated capacitors in the dimension required to fit the space. Both width and height and the all-important lead pitch. Of course, this is all dependent on how fussy you are in terms of aesthetics. Just don't over paid for some Audiophile cap that promises to deliver that missing Mojo.

[RectifiedAmps]

I’ve heard that ESR increases with voltage rating on caps, so the trick is to get ones that have a rating higher than they’ll see in the circuit, but not excessively higher. So avoid using 400v 22uf caps in situations where they’d only see 5-10v (like cathode bypass caps in tube amps).

But in your case just replace like for like and you’ll be good.

[StrummersOfThunder]

I’ve heard that ESR increases with voltage rating on caps, so the trick is to get ones that have a rating higher than they’ll see in the circuit, but not excessively higher. So avoid using 400v 22uf caps in situations where they’d only see 5-10v (like cathode bypass caps in tube amps).

But in your case just replace like for like and you’ll be good.

Ok cool
So I’ll get esr for power section , standard polar caps for elsewhere , all of a decent name brand and just go for same values that I’m pulling. I doubt physical size will be an issue as the caps I’m seeing to replace the 1970s ones seem to be tiny in comparison

[Jay]

I’ve heard that ESR increases with voltage rating on caps, so the trick is to get ones that have a rating higher than they’ll see in the circuit, but not excessively higher. So avoid using 400v 22uf caps in situations where they’d only see 5-10v (like cathode bypass caps in tube amps).

But in your case just replace like for like and you’ll be good.

Ok cool
So I’ll get esr for power section , standard polar caps for elsewhere , all of a decent name brand and just go for same values that I’m pulling. I doubt physical size will be an issue as the caps I’m seeing to replace the 1970s ones seem to be tiny in comparison

Not sure what you mean by"polar caps'.

I suspect you are talking about polarised capacitors which have a plus/minus indicator on them. Putting them in the circuit the wrong way is not good!

The audio section of the circuit is not exposed to extreme frequencies so normal aluminium electrolytic capacitors are fine.

By all means, get low ESR caps for the power section but follow RectifiedAmps' advice above.

[StrummersOfThunder]

I’ve heard that ESR increases with voltage rating on caps, so the trick is to get ones that have a rating higher than they’ll see in the circuit, but not excessively higher. So avoid using 400v 22uf caps in situations where they’d only see 5-10v (like cathode bypass caps in tube amps).

But in your case just replace like for like and you’ll be good.

Ok cool
So I’ll get esr for power section , standard polar caps for elsewhere , all of a decent name brand and just go for same values that I’m pulling. I doubt physical size will be an issue as the caps I’m seeing to replace the 1970s ones seem to be tiny in comparison

Not sure what you mean by"polar caps'.

I suspect you are talking about polarised capacitors which have a plus/minus indicator on them. Putting them in the circuit the wrong way is not good!

The audio section of the circuit is not exposed to extreme frequencies so normal aluminium electrolytic capacitors are fine.

By all means, get low ESR caps for the power section but follow RectifiedAmps' advice above.

Yep sorry phone type polar = polarised

Thanks Jean