Using three different op amps?

[enginefire]

For sure giving more details about what you are trying to get out of your mods will help!

E.g. how you use your mixer (for mixing?  Using only preamp for direct outs?)

Maybe transformers on the outputs?

 

[ruairioflaherty]

Keala,

It's really great that you are interested in electronics and willing to get your hands dirty.  It's even better that you now have a specific goal in mind, some distortion and specifically odd order.

Your console is probably not the place to start.  It's a relatively complex circuit, and there are all sorts of limiting factors on what components you can just drop in.  As an aside I find eqs that distort not to be useful for my work (despite the persistent myths that say otherwise).

So instead of trying to turn a saucepan into a toaster, why not just build the toaster that you want?  You will learn more, and have a specific known result.  Even better if you decide you don't like it or outgrow it you can sell it here.

Take a look at this project, it seems perfectly suited to what you require - https://www.diyrecordingequipment.com/collections/colour

 

[buildafriend]

you can add a bit of odd order distortion with a diode or two. maybe even with an analog vu meter with no buffer going to it. see diode clipper or diode limiter

 

[Keala]

For sure giving more details about what you are trying to get out of your mods will help!

E.g. how you use your mixer (for mixing?  Using only preamp for direct outs?)

Maybe transformers on the outputs?

I mostly use it for the pre's
i'm trying to get less noise and more warmth

I think i'm gonna' recap and chage op amps


How would i go about implementing transformers?

 

[Keala]

Keala,

It's really great that you are interested in electronics and willing to get your hands dirty.  It's even better that you now have a specific goal in mind, some distortion and specifically odd order.

Your console is probably not the place to start.  It's a relatively complex circuit, and there are all sorts of limiting factors on what components you can just drop in.  As an aside I find eqs that distort not to be useful for my work (despite the persistent myths that say otherwise).

So instead of trying to turn a saucepan into a toaster, why not just build the toaster that you want?  You will learn more, and have a specific known result.  Even better if you decide you don't like it or outgrow it you can sell it here.

Take a look at this project, it seems perfectly suited to what you require - https://www.diyrecordingequipment.com/collections/colour

I have been looking at these fun little kits. But aren't those for the 500 series platform, or could i find other use for them?

 

[Newmarket]

Your console is probably not the place to start.  It's a relatively complex circuit, and there are all sorts of limiting factors on what components you can just drop in.  As an aside I find eqs that distort not to be useful for my work (despite the persistent myths that say otherwise).

So instead of trying to turn a saucepan into a toaster, why not just build the toaster that you want?  You will learn more, and have a specific known result.  Even better if you decide you don't like it or outgrow it you can sell it here.

Take a look at this project, it seems perfectly suited to what you require - https://www.diyrecordingequipment.com/collections/colour

+3 and those kits look great. Wasn't aware of them so thanks for the info.

 

[ruairioflaherty]

I have been looking at these fun little kits. But aren't those for the 500 series platform, or could i find other use for them?

Yes, they are 500 series but you could build them outside of a 500 rack, it just means dealing with mains power etc.

Based on your following comment about using your console for pres you could consider making a great pre, something like a DIY API 312 from ClassicAPI.  They are easily built and sound great.

The opamps are only one contributor to noise in a console.

 

[Keala]

well.. instead of trying out fancy DOA's for this rather cheap mixer (still sounds kinda good) i've decided to get some 5532's
https://www.elextra.dk/main.aspx?page=article&artno=H23707

 

[Keala]

Also.. now i'm facing the task of having to change about 30 op amps. Can i just desolder each pin without doing damage to the pcb? i read that it was quite difficult to do. I found a post on a forum that said i either had to destroy the circuit board or the op amp to remove the op amps. It also said something about the op amp overheating.

Any guidance/tips on what to do would be greatly appreciated

 

[ruairioflaherty]

First off, the golden rule of modding anything - Only change one thing at a time…  Do one channel and listen and evaluate carefully before doing any more, it may well sound worse than what you have.  It's likely that it will sound slightly different but not better.

You will very possible do damage to your PCB if you haven't removed ICs before and this can be very tricky to fix when traces get lifted.  There are endless videos on youtube about soldering and desoldering, watch those and then practice on a junk board before  working on your console.

 

[enginefire]

Well the good news is that the pcbs are only one sided!  Makes things WAY easier.

Get a solder sucker they're like $5 and makes desoldering a snap.  Heat up the leg and press the button and snap out comes the solder.  Repeat x7 more times and all the legs should be more of less free .  I like to make sure they can move a bit with the tip of my iron or a flat head screw driver.  Then heat up all 4 on one side while prying gently up on the other side with the same small flat head screw driver.  The op amp should move a bit.  Then do the other side and the thing should pop out.

Other people prefer clipping the legs off first and then just desoldering the waste one hole at a time.

Next install machined sockets.  Now insert your replacement op amp.  Pay careful attention to its orientation or you will release the magic smoke.

You can also try other op amps (opa2134 is particularly popular).

Check to see if the circuit already has decoupling, which are 0.1uf ceramic caps going from pins 4 and 8 to ground.  These help stabilise the op amps esp new fancy ones .  5532 will probably be ok if they're not there but you'll have to see.

Practice desoldering before on something useless.  Old motherboards for caps, may be a junk stereo or CD player for op amps?  See what you can find to sacrifice!

Definitely do one channel first.

Try one channel with new op amps and another with new electrolytic capacitors.  Hear the differences.  Then do both.  Both are important imho.  I'm not a big fan of 4558s except in tube screamers.

 

[Keala]

Well the good news is that the pcbs are only one sided!  Makes things WAY easier.

Get a solder sucker they're like $5 and makes desoldering a snap.  Heat up the leg and press the button and snap out comes the solder.  Repeat x7 more times and all the legs should be more of less free .  I like to make sure they can move a bit with the tip of my iron or a flat head screw driver.  Then heat up all 4 on one side while prying gently up on the other side with the same small flat head screw driver.  The op amp should move a bit.  Then do the other side and the thing should pop out.

Other people prefer clipping the legs off first and then just desoldering the waste one hole at a time.

Next install machined sockets.  Now insert your replacement op amp.  Pay careful attention to its orientation or you will release the magic smoke.

You can also try other op amps (opa2134 is particularly popular).

Check to see if the circuit already has decoupling, which are 0.1uf ceramic caps going from pins 4 and 8 to ground.  These help stabilise the op amps esp new fancy ones .  5532 will probably be ok if they're not there but you'll have to see.

Practice desoldering before on something useless.  Old motherboards for caps, may be a junk stereo or CD player for op amps?  See what you can find to sacrifice!

Definitely do one channel first.

Try one channel with new op amps and another with new electrolytic capacitors.  Hear the differences.  Then do both.  Both are important imho.  I'm not a big fan of 4558s except in tube screamers.

Thanks for the tips. It was really helpful. I have a solder sucker. I'll get started practicing tomorrow. I have an old Roland CPM-120 that i salvaged the toroidal transformer from. There's a couple of IC's in there that i could practice on. Can't wait to hear the result when i get it done. Well that's if i do get it done and don't fail miserably. If do get it recapped and get some 5532's in there, i could post some audio demos, if not.. I'll buy you a beer if you ever come to Denmark.

 

[enginefire]

Take your time, don't rush, be patient... All things I had to learn the hard way when working on modding consoles!  Like the other poster said, lifted pcb traces really suck.

Watch out for your solder sucker even, if it's too powerful it can lift the trace.

Try doing just the op amps 1st on one channel.. Or recapping the power supply for the whole console (that's usually the lowest hanging fruit plus if you really mess it up you can easily replace a psu). 

Good luck!  Are you in Copenhagen ?  I'll take you up on that beer next time I'm around there!

 

[Keala]

Take your time, don't rush, be patient... All things I had to learn the hard way when working on modding consoles!  Like the other poster said, lifted pcb traces really suck.

Watch out for your solder sucker even, if it's too powerful it can lift the trace.

Try doing just the op amps 1st on one channel.. Or recapping the power supply for the whole console (that's usually the lowest hanging fruit plus if you really mess it up you can easily replace a psu). 

Good luck!  Are you in Copenhagen ?  I'll take you up on that beer next time I'm around there!

Well my solder sucker almost can't even suck up solder, so for it to suck up pcb traces would be mind blowing.
I'm going to practice for a while on an old Roland CPM-120 before i go over to the yammie

No i'm not in Copenhagen. I live in a small town in East Jutland. If you come to East Jutland then it's a deal haha

 

[keefaz]

Desoldering 30 opamps with just a simple sucker seems a long time task.
It can be done but if you go too fast, you will damage the pcb.

It helps to add a bit of fresh solder to the pad just before sucking solder away.

 

[Keala]

Desoldering 30 opamps with just a simple sucker seems a long time task.
It can be done but if you go too fast, you will damage the pcb.

It helps to add a bit of fresh solder to the pad just before sucking solder away.

I guess i'll just use my good old soldering iron and a pair of pliers.