Mini SSL 5000 Mixer build thread (Revisited 2015)

[DigitalMetal]

*EDIT* Ive decided to make this a build thread for my Mini SSL 5000 Mixer

Hi,

Im a bit of a novice when it comes to power supplies and the finer points of electronics generally but am perfectly happy soldering and wiring audio circuits.
I have a project where im making a little hybrid setup from some SSL 5K modules and need some help with a power supply soloution.
Ive read through the PSU Meta but havnt found anything that goes exactly with what i need.

I have 8x stereo line modules and 3x (and increaseing in number slowly) Eq modules from a SSL 5k

What i need is a power supply that can run all of this and maybe a couple more EQ's in the future.

They all use +/- 18v , -24v and i think i need a -6 too but ive not confirmed that yet.

Simple question is to avoid getting into designing and building a PSU can i buy a couple of power supplies like this:

http://cgi.ebay.co.uk/DC-18V-10A-Universal-Regulated-Switching-Power-Supply-/170528619090?pt=UK_BOI_Electrical_Test_Measurement_Equipment_ET&hash=item27b44c3a52

and this

http://cgi.ebay.co.uk/24V-10A-DC-Universal-Regulated-Switching-Power-Supply-/140315138784?pt=UK_ConsumerElectronics_PowerAdaptors_SM&hash=item20ab6f1ae0

,

Then on each supply link the + and - of one of the dual sides to get my 0v and end up with a + 0 - PSU ?

Is there anything wrong with these types of PSU for audio use? (they seem darn cheap for what you get is that bad?)

i was just going to rack them up in maybe a 2U rack case and away i go,

Any thoughts pointers/help?

Thanks

Neil

 

[Matt Ward]

Hi,

Long story short; don't do it.  Those are cheap switching power supplies (or Switch Mode Power Supplies).  Read up about them and Linear Regulated Power Supplies...

(apols for the short post - could write an essay on this and don't have time...)

Matt

 

[DigitalMetal]

Hi Thanks for your input,
What is the big "No No" about using switch mode regulated supplies ?
They seem acceptable enough for very sensitive equipment like Computers,

I read this:
http://wapedia.mobi/en/Switched_mode_power_supply

And it seems the biggest disadvantage could be that a SMPS "could" introduce noise onto the supply of other equipment, but seing as i have several computers in my studio setup theres no difference to me there.

Could you tell me any other reasons?

Thanks for your help !

 

[Matt Ward]

I didn't say all switch mode power supplies are "no-nos".  I said that cheap switch mode power supplies are.  There is a big difference.

The SSL 9k runs off switch modes.  SMPS are not, in my opinion, inappropriate for audio devices per se (although some do think that).  They are, however difficult to optimise for audio applications.  Linear power supplies are not.  An off the shelf cheap SMPS is likely to be insufficiently filtered and have an inappropriately low switching frequency to supply low noise audio circuits.  I'm sure this has been covered around here before...

Anyway searching here for switch mode yields:

http://www.groupdiy.com/index.php?topic=3710
http://www.groupdiy.com/index.php?action=printpage;topic=19733.0

I'm sure there's more out there on the web.  Seek and ye shall find.

Matt

 

[DigitalMetal]

Ok thanks,
Again after reading more the only disadvantage seems to be the fact that SMPS can introduce noise onto equipment.

If i try the type of PS i linked to in the original post and i test for noise with a high quality analyser (Neutrik A2) and everything seems fine, is there anything else i should look out for that makes a SMPS a bad idea?

 

[SSLtech]

Joe Malone makes a kit. It's wonderful.

I myself used the prototype of the 9k clone mic preamp power supply to power my 5k modules, which gave me plus-and-minus 18V for the audio, +48V for the phantom, and I took a sniff of the raw approx. 24V for the stuff which needs that. -It all cost me buttons to build, though it might not do more then a couple of modules at a time.

Go with the Joe.

Keith

 

[DigitalMetal]

Hi Keith,
Yes i have some of Joes Power station kits at the moment but was hoping to make one power supply to run everything,
I did see you had made a 9k PSU but all the links to the schematics seem to be too old and dead.
What kind of current could that run on the +18v and -18v ?
Is that an ok think to do - taking the raw feed from the transformer for your 24v ? does it not need regulating at all?
I may end up having to just use several of Joes power stations i guess but i thought there might be an all in one solution out there.

Thanks very much

Neil

 

[s2udio]

You mean this one ?
http://www.studio21.ch/diy/neeno/ssl9k/DIY_9k_Preamp.pdf

 

[DigitalMetal]

Ah ok thanks i was searching for the kps-1 as i believed thats what Keith named it?

If i were to build this supply is there a simple way to modify the design to run at 5Amps per rail for example

 

[DigitalMetal]

Is there anyone who can point me toward some help with this PSU i really want to build a single psu that can supply 16 SSL 5k modules (8 stereo line in and 8 stereo EQ's) i have all the modules now and am building them into a rack at the moment.
I really want to get started on the PSU but need some help with a design.
I really want to avoid having to buy 8 JLM power stations if i can and just make one big PSU.

id love to design one myself but dont really have the skills to do it safely, but im sure i could make one from a drawing.

 

[helterbelter]

I have contacted a company in china that make linear dual rail PSU kits to ask if they have an +/- 18VDC version that will run up to about 5 Amps  -i think that should be enough do you?

5 amps .... I guess it will be enough, but I'm not an expert regarding the powerconsumption of different modules, and for which voltagerails.

i am always searching ebay for an SSL Power supply but they never seem to come along, i will get in touch with Recycled Audio how much do you think would be a fair price for a 5K PSU second hand?

I have no idea what they will charge, but asking doesn't hurt, right ?
By the way, there has been one available on ebay (USA) about 4 months back, for a very nice price. Unfortunately, it's not listed anymore (just checked it).

 

[DigitalMetal]

Ok thanks i have sent a message to Recycled Audio to see if they have a PSU for sale,

I found these units on ebay.com


SSL power supply changeover unit CF663

http://cgi.ebay.com/SSL-C663E-Power-Supply-Changeover-unit-6000E-Console-/200268448481?pt=LH_DefaultDomain_0&hash=item2ea0ee02e1#ht_904wt_905

http://cgi.ebay.com/SSL-power-supply-changeover-unit-CF663-4000-/260759779949?pt=LH_DefaultDomain_0&hash=item3cb67e7a6d#ht_500wt_1156

Are they just switching units to change between 2 different PSU's for redundancy? or actual power supplies? dont worry if you dont know maybe someone else will chime in.

Thanks  !

 

[kante1603]

Is there anyone who can point me toward some help with this PSU i really want to build a single psu that can supply 16 SSL 5k modules (8 stereo line in and 8 stereo EQ's) i have all the modules now and am building them into a rack at the moment.
I really want to get started on the PSU but need some help with a design.
I really want to avoid having to buy 8 JLM power stations if i can and just make one big PSU.

Hi Neil,

I remember our psu-racks-they were huge(o.k.,redundant but huge)!The console produced lots of heat,but mainly in the centre section.
You wrote some posts ago that you already have Joe´s powerstation-psus,no?
Maybe it would be a good idea to hook up just 1 or 2 modules to it and the measure the current on the 3 rails you need.
Have found an old link where a guy seems to have measured some modules;not shure if these are correct but to give you an idea:
http://recording.org/diy-pro-audio-forum/42188-ssl-5000-casettes-racking-up.html
I don´t think you will need 8 of jlm psus as a powerrail gives you a max. of 6amps (with optional 6A bridge in theory),shared between the rails.
One can provide a max. of 1,5amps,i´d say 1,2-1,3 to be on the safe side.
Think of serving your modules as bays meaning serving them in groups of xxx modules.
Our consoles psu had a lot of rectifier and regulator cassettes as far as I can remember-I had to trim them sometimes while beeing guided by Pete Farley on the telephone from england-at christmas time .....hahahahaha.
We have some cadac consoles here,and on our main console (J-Type,formerly Concertboard) it´s the same:Several psus serving several bays;I have a bunch of 8(!) big psu cables at the back of it!
So if you have a DMM then measure it please-would be very interested in the results!

Have fun,

Udo.

Edited/deleted the jlm-psu-mod:This was for getting a positive 5th rail while we need a negative one (-24V for logic) here-oooops-sorry!

 

[helterbelter]

Ok thanks i have sent a message to Recycled Audio to see if they have a PSU for sale,

I found these units on ebay.com


SSL power supply changeover unit CF663

http://cgi.ebay.com/SSL-C663E-Power-Supply-Changeover-unit-6000E-Console-/200268448481?pt=LH_DefaultDomain_0&hash=item2ea0ee02e1#ht_904wt_905

http://cgi.ebay.com/SSL-power-supply-changeover-unit-CF663-4000-/260759779949?pt=LH_DefaultDomain_0&hash=item3cb67e7a6d#ht_500wt_1156

Are they just switching units to change between 2 different PSU's for redundancy? or actual power supplies? dont worry if you dont know maybe someone else will chime in.

Thanks  !

These are of no use to you.

I have thought a bit more about your PSU question last night, and I also thought that a few JLM's will do nicely, also budgetwise. I remember reading a (recent) post of a german forummember, who powered 8 modules (4x 501 and 4x 502) from just one JLM powerstation, with adequate heatsinking.
So, I think when you put together a PSU consisting of 4 to 6 JLM's, you'll be there, and you have a bit of headroom as well.

However, how to set these up, is a thing I have to think through a bit more. Also with regards to heatproduction.
(I described a mod for the JLM in my 552 thread which significantly decreases heat. This changes the +48v rail into -24v, allowing to use a dual 15v transformer, with the result that the 317's and 337's don't have to dissipate 6 to 7 volts, and therefore don't get that hot. The downside is that the -24v rail isn't as powerful as the other lines, but the logiccircuits in the modules aren't that consuming either.)

So, iow, you can set both the +ve rails to 18v, both of the -ve rails to -18v, and the doubler rail to -24, and then you already will get  a lot more juice from the JLM than the standard.

But then : the coupling..... It'd be best to wire the JLM's parallel, but you'll need to put diodes at each output, so you'll get a voltagedrop of 1.2 - 2V on each rail....... I don't know if the JLM with the mod I just described (including a dual 15v tranny) will be up for delivering enough volts... I'll have to test.... I'll get back to this later (probably tomorrow).

ah, well, let me think a bit more about this. It's also a possibility to use different regulatorcards for the different voltagerails.

Have found an old link where a guy seems to have measured some modules;not shure if these are correct but to give you an idea:
http://recording.org/diy-pro-audio-forum/42188-ssl-5000-casettes-racking-up.html

Great ! This underlines what I just said : "but the logiccircuits in the modules aren't that consuming". So, I'll work out my idea about the jlm powerstation tomorrow.

 

[pyjaman]

One kit to consider, asside from jlm one, would be to look at what could be done with a 51X PSU. might be slightly modded to suit your needs and might have enough power too...
Laurent.

 

[DigitalMetal]

Wow thanks guys this is fantastic info you are coming up with here,

ok so maybe a genuine 5k PSU will be a bit overkill and perhaps expensive, JLM Powerstations are a very good price.

I have 2 JLM power stations i can try this modded idea with,
i did think about the 5XX series PSU's but seeing as i have the JLM's they will be a good place to start with, im interested to know what the current ability of the group buy 5XX PSU is, i cant seem to find spec's on it.

I did test the current draw on a stereo input module when i first got them and i seem to remember that if i aimed for 200mA per module (18V Rail) i would have enough head room and the -24 was hardly anything at all, so the thread Udo linked to's figures look very familiar.

I do actually have a 24V switch mode 10A open frame PSU that i could use for the logic supply and just use the JLM's for the 18-0-18 supply but how would i go about getting -24 V from it when it only has +24V and 0V output ?
Or should i steer clear of the SMPS all together? and go with what looks to be a great idea you have Helterbelter?

 

[kante1603]

I do actually have a 24V switch mode 10A open frame PSU that i could use for the logic supply and just use the JLM's for the 18-0-18 supply but how would i go about getting -24 V from it when it only has +24V and 0V output ?
Or should i steer clear of the SMPS all together? and go with what looks to be a great idea you have Helterbelter?

Hello Neil,

here´s a quote of helterbelter´s sl552-thread:

The -24v rail is just for logic so doesn't need to be regulated.
So u could just tap off the -24v (ish) after the bridge and filter caps of your psu if using a 18-0-18vac transformer.

That seems to be the easiest way to get a negative voltage arround -24V (-18V after the reg/Caps * 1,4xxx=-25V:not bad!)

Or you go the way that helterbelter described in the same thread by reversing the doubler:

If you're building a PSU solely for the 552, you could also use the 3 rail psu, and reverse the doubler rail into a negative doubler rail : You should reverse the caps and the diodes in the doubler circuit (including the chargepumpcaps), and use a 337 instead of a 317. This way a dual 15VAC torroid will do the trick. Note that the pinout of a 337 is different than the 317, so you should wire this one offboard.

I would stay off of smps-too much dirt in general.And you might get trouble in getting the 0V if mixed up with the powerstation(s).
The first idea seems to be a good way because you can get a lot of current from there if wanted,but I don´t believe it´s needed because it´s just for logic (master-reset) which doesn´t seem to need much.

Cheers,

Udo.

 

[DigitalMetal]

Hi Udo,

Ok thanks very much thats what i will do,
I will need to get a 18-0-18 transformer and then i will give it a try, i just need to sit down and work out how bit i need it to be to cover 6 JLM's and il be sorted,
I really appreciate all you reassuring help guys, you've been great !

 

[DigitalMetal]

ok so have i got this right?
To spec my 18-0-18 transformer i just need to allow 6 Amps for every JLM PSU i want to use?

So for 4x JLM PSU's that should power 16 Modules ok
(according to Helterbelters memory of the German forum member running 8 modules from 1 JLM PSU)

Using this rule i found on another website:
Load ratings for transformers are usually given as VA or kVA, these are obtained by multiplying the load current by the supply voltage: this gives the volt-ampere (VA) rating, where 1000 VA = 1 kVA. This is often loosely referred to as the "power" rating of the transformer.

4x 6Amp = 24Amp
24Amp x 18Volts = 432VA

Is this correct?

Now i cant actually find a 432 VA 18-0-18 Transformer the closest i can find is a 500VA 24-0-24

I could make 2 separate power supply's with 225VA 18-0-18 transformers (if i half the equation above i will need 216 VA so a 225VA transformer should cover my needs right?

I hope im making sense of this

Does anyone have any better suggestions?

 

[kante1603]

ok so have i got this right?
To spec my 18-0-18 transformer i just need to allow 6 Amps for every JLM PSU i want to use?

4x 6Amp = 24Amp
24Amp x 18Volts = 432VA

Is this correct?

After the math yes,but you´re calculating the max. current a powerstation can derive-this is shared between all rails while 1 rail should not exceed 1,5As.

Now i cant actually find a 432 VA 18-0-18 Transformer the closest i can find is a 500VA 24-0-24

Seems a bit overkill to me....may I suggest to do some current measurements with a single PSU and some single modules first and then add up the values...I think you´ll end up at much  lower currents.And be aware of that the different modules will need significantly different currents.From what I´ve read in the other forum e.g. an input module "eats" more than an eq module etc.
Funny that nearly nobody who wanted to rack 5k modules ever seemed to measure this-time´s up!

I could make 2 separate power supply's with 225VA 18-0-18 transformers (if i half the equation above i will need 216 VA so a 225VA transformer should cover my needs right?

Yes,making separate psus can make sense-thinking in bays (e.g. 4 modules each or so),if a failure occurs on one the others will keep on working-nice!
Except of the summing amp fails of course

So if I were you I´d start some measuring (with a signal generator on inputs at a high level)-would help other members too (including me).

Best regards,

Udo.