Turtlerock Forum

From memory, Rob uses +24v DC regulated switchmode power supplies for his racking of channel strips..
(Laptop style power supplies)

I was hoping Rob could chime in and point out what model he uses etc.. Or if anyone else has any recomendations?

I've just finished a Neve 1084 EQ Clone (EZ1084eq) and it's wicked.. the only problem is the $8 Power supply I'm using is throwing out a lot of hash, and I'd like something a bit more quiet.

Cheers
Mike

Hi mike
I used an altronics power pack across my 1290's.
Altronics have a range of supplies that might suit what your looking for. Look under "power supplies" then "power packs".
I really wanted to tackle the ez1084 but can't find any free DIY time. I've got 4 x 312 boards that i need to populate and rack but that might be a January project.

And err.. Photo's please

I've used Altronics M8970A and M8973 for 24V supplies. Though I can't say if I've ever used them for Neve modules. The SMPSUs I have used for Neve stuff involves one of JLMs 48V SMPSUs and then a Trex to give 24V. This way I also have the 48V for phantom.
But Neves are very sensitive to having a really clean and stable supply and as you've found out many SMPSUs won't cut it.
When using SMPSUs I always add some filtering on the output, say 10R or 22R 2watt in series followed by 2,200uF post the resistor in parallel. Most of the stuff I've done using the Altronics supplies (which are pretty clean anyway ) are things like Telefunken or Neumann modules that have an internal power requlation and supply cleanup circuitry.

Cheers for your input.. that helps lots.

I've just gotta mix and match some vintage knobs, but yea, I'll post Pics.

It's a very nice EQ as expected.. I've only spent a little time with it running my Ipod through it while testing etc, but it's one of those EQ's where you can boost anything, and while it may not be appropriate for the sound/track, it always sounds very good.

I also like the 2 different bypass modes the EZ1084 has.. a true hard bypass (With relays) and a 'soft' bypass that bypasses the EQ section (With relays) but still uses the input & output transformers and gain. hmmmm.

me like.

Not the cheapest of DIY's I've done.. I think the total bill was around $600+ for everything (minus labour)

I was thinking it'd be easiest + cheapest to use a 24VAC plugpack, and then put a simple bridge rectifier + regulator circuit in the box... only niggle with that is then I'd have non standard 4 way XLR power connections, and other stuff uses the same pinout, I suspect... first should should probably measure the current draw with it under load, and see how possible that is.

As for the cost, I'm glad we only got one each.

no-fi wrote:I was thinking it'd be easiest + cheapest to use a 24VAC plugpack,.

Already thinking exactly the same.. I found an unused 24v AC power supply lying around.. If I find another, I'll flick it your way.

Rectify / smooth / regulate.

I'm not to concerned about the 4pin XLR pin out convention.. Thats the only thing I have with a 4 pin XLR.

Hi guys,

Allow for a 1 amp 24 volt DC supply.

Neve's need a lot of headroom in the PSU, good filtering and good grounding.

Keep the PSU external... that's how Rupert would do it.

I'm not sure about the wall wart idea... fine for the Beri stuff but not the way to go on a Neve.

I think JLM has a schematic for a combined 24v/48v supply, they also have PCB's.

http://www.jlmaudio.com/JLM%20Power%20Supply.htm

You've spent all that time and effort building a 1084 clone, now spend a little bit more time and money building the power supply it deserves.

Just my opinion for what it's worth.

Greg

that JLM configuration recommended for neve gear is just transformer 24VAC -> rectification -> regulation anyway...

the difference of whether we have the transformer inside the box or at the power point is only a difference of arrangement, not design.

Mnats (of diy 1176 fame) has just released a 24v/48v power supply on a small board. Total build cost (excluding transformer) is around $30-$35. In the middle of trying that out on a job I'm doing atm, so I'll let you guys know how that works. Could be a good reasonable option for preamps.

no-fi wrote:the difference of whether we have the transformer inside the box or at the power point is only a difference of arrangement, not design.

often the difference of a mains transformer in or out of the case is the amount of induced hum and buzz. This is particularly so in devices that use transformers and especially inductors. This is where SMPSUs have a significant advantage, as does keeping the transformer out of the case. Of course all this can be negated once you bolt it into a rack with other units containing mains transformers above and below.