PSU for 16 channels API mixer

[iprovlek]

Hi guys planning to built my own PSU for my API 16 channels mixer!!!

I found this schematics for it!!!

I need advice is this schematics can be used for it???

 

[Rob Flinn]

You would need to add some regulation to that to bring the rails down to + & - 16v

 

[iprovlek]

http://sound.whsites.net/project30c.htm


Here is link for it....

 

[iprovlek]

Regulators....

 

[iprovlek]

Phantom.....

 

[Rob Flinn]

That looks like it would work.

 

[Bo Deadly]

Hi guys planning to built my own PSU for my API 16 channels mixer!!!

I found this schematics for it!!!

I need advice is this schematics can be used for it???

I think some people think that linear supplies are somehow better than switching mode supplies but if done correctly, SMPS can be very quiet. And SMPS have so many other benefits, I don't know why anyone would use anything else. You can get off-the-shelf AC/DC SMPS modules that are very small and efficient. For an SMPS 25A is easy whereas for a linear supply you have to be careful or something could start smoking.

The PSU that I'm using right now is a few MeanWell AC/DC SMPS, some large, high-Henry common mode chokes and filter caps (which can be relatively small compared to a linear supply BTW) in an external 1U rack enclosure and then at the remote end I have the usual regulation to get the desired voltages.

I just tested a simple API style mic pre and the noise floor is very good. There's maybe a little hash in the 15KHz range but at a level that is totally inconsequential (-110 dB after 40dB gain).

 

[iprovlek]

Thanks a lot Squarewave!!!!

I never thought about switching power!


Maybe this can be good choice for me....

 

[Whoops]

Regulators....

Well 78xx and 79xx provide 1 amp to 1.5 amp maximum current.
I guess you need much more than that for a 16 channels API mixer.

I guess you would need something like 3 Amps per rail or more depending on the complexity of the mixer.

 

[Brian Roth]

Well 78xx and 79xx provide 1 amp to 1.5 amp maximum current.
I guess you need much more than that for a 16 channels API mixer.

I guess you would need something like 3 Amps per rail or more depending on the complexity of the mixer.

I'm just getting caught up with this thread....Real Work to be done the past 2 days ...lol!

To the OP,  iprovlek...

I'm slightly confused on portions of your question... perhaps COLD weather here in Kansas vs. an Old analog guy!  <g>

Define what you mean when you describe your "16 channels API mixer".  Is this a console, or some sort of small mixer which uses API components? 

The size of this "machine" will help decide which powering method(s) are the best.

Define the required voltages, and the current requirement for each of those voltage rails.

That will help us to make suggestions.

<g>

Bri

 

[gridcurrent]

specifications for the 2520 are published.
worst case, 60 mA @ bipolar 15 VDC.
an API 528 module uses 2 plus the peak detector;
plus your summing, line amps, and auxes.
you can do the math.
regarding switchers, if you are building something vintage, why fool around with a trendy but often noisy power system.
it kinda doesn't add up.
either go 100% modern with smps and those fancy low noise ic op-amps,
or vintage API with linear power.

 

[iprovlek]

YES BRIAN I WAS NOT SO ACCURATE ABOUT IT!!! Im sorry on COLD WEATHER IN KANSAS but Im sure that this will heat up a little!!!

Im planning to use 16 API312 ,16 eq Studer 169 500series,16 active fader, 16 route passive switch and 9 summing amps,8 for groups and one for MASTER!!!

Practically the hole API mixer!!!

I think use +/-18 VDC with 48V phantom ,and will need +12VDC for VU meters!!!


So I stuck with this PSU!!! I dont have knowledge and experience for this hard project, but practically all components are

almost finished and works AND ILL DONT GIVE UP OF IT....If you understand me!


BUT THANKS YOU GUYS THAT YOU HELP ME ABOUT THIS...


But I find this site (link is above) that I find PSU for mixer that need about 4A of current, at least it is write on it!!!

 

[iprovlek]

So I find this site  http://sound.whsites.net/project30c.htm

And guy Rod Elliot swrite about this....

 

[Whoops]

Im planning to use 16 API312 ,16 eq Studer 169 500series,16 active fader, 16 route passive switch and 9 summing amps,8 for groups and one for MASTER!!!

I think use +/-18 VDC with 48V phantom ,and will need +12VDC for VU meters!!!

What's the consumption of each studer 169 EQ?

What's the consumption of each active fader? Do you have schematic for it?

How many 2520 opamps each summing amp has?

 

[iprovlek]

Here is the schematics of EQ!!!

 

[iprovlek]

Im using Jeff ACA-inv summing amp and there are four opamps on one PCB!!!


http://capi-gear.com/catalog/product_info.php?cPath=22_46&products_id=412

And schematics...

 

[iprovlek]

Active fader use one opamp!!!

 

[Rob Flinn]

I think some people think that linear supplies are somehow better than switching mode supplies but if done correctly, SMPS can be very quiet. And SMPS have so many other benefits, I don't know why anyone would use anything else. You can get off-the-shelf AC/DC SMPS modules that are very small and efficient. For an SMPS 25A is easy whereas for a linear supply you have to be careful or something could start smoking.

The PSU that I'm using right now is a few MeanWell AC/DC SMPS, some large, high-Henry common mode chokes and filter caps (which can be relatively small compared to a linear supply BTW) in an external 1U rack enclosure and then at the remote end I have the usual regulation to get the desired voltages.

I just tested a simple API style mic pre and the noise floor is very good. There's maybe a little hash in the 15KHz range but at a level that is totally inconsequential (-110 dB after 40dB gain).

I've had to deal with a desk that had a bunch of these PSU's to make a 5 rail supply before & it really didn't work.  Despite bags of current in hand you could not put all the channel strips in without the relays in the desk going crazy switching on and off rapidly, & the desk was very noisy in an HFswitching sort of way.  Maybe it was somethng to do with the inductive load of the relays.

I know that you can get differing qualities of Switch mode PSU.    Cyril Jones was supplying PSU's for his Raindirk Sympony made of Thurlby Thander switching bench PSU's that worked very well & took up a fraction of the space of the 2 really heavy 6u linear supplies they originally had.    So I think a little caution is useful here.

 

[iprovlek]

I bought LM338 positive regulator in electronic shop and guy recommended it cause he gives 5A.....

So I googled and find this sites

http://www.decdun.me.uk/Pedja-Rogic/pedja-gc_decdun/pedja-gc_decdun/supplies.htm


http://alectronicx.blogspot.hr/2010/07/power-supply-20v-and-20v-5a-by-lm338.html


http://alectronicscircuits.blogspot.hr/2010/07/12v-12v-5a-regulated-power-supply-by.html

 

[Whoops]

I've had to deal with a desk that had a bunch of these PSU's to make a 5 rail supply before & it really didn't work.  Despite bags of current in hand you could not put all the channel strips in without the relays in the desk going crazy switching on and off rapidly, & the desk was very noisy in an HFswitching sort of way.  Maybe it was somethng to do with the inductive load of the relays.

I know that you can get differing qualities of Switch mode PSU.    Cyril Jones was supplying PSU's for his Raindirk Sympony made of Thurlby Thander switching bench PSU's that worked very well & took up a fraction of the space of the 2 really heavy 6u linear supplies they originally had.    So I think a little caution is useful here.

Very Good Point.