Eventide H3000 power transformer

[mobyd]

Have a customer with an H3000 in which the power transformer is the loudest (acoustically) thing in the control room. These puppies just don't cope well with 50Hz flavoured power. Any alternatives (230v) to the "Studio Electronics" rather expensive replacements?. Temptation is to chuck in a Meanwell SMPSU.
M

 

[mikeyB]

Hi Mobyd,
Check the bolts on the transformer. I opened one up years ago and the bolt head had come clean off from the shank!! Luckily the head wedged between wires so nothing shorted!! It sounded like a buzz saw. Other bolts were loose, I think the tx lams were chattering like the wind up teeth! All tightened up and good to go!
I've had similar thing on MOTU interface were the loose bolt is rattling loudly. On the 3000, it might be worth mounting on grommets, but REMEMBER about electrical continuity for the tx

 

[soapfoot]

These things are famous (notorious?) for this.

I have no answers, but if anyone else does I’d be interested as well—I have an H3000 that’s quite audible when powered on, even on 60Hz mains

 

[Whoops]

Is the noise coming straight from the transformer?
or is the transformer coupling with the case making the case vibrate?

If the noise is only from the transformer itself, dipping it in varnish might solve it. I would do 3 dip cycles. Dip it and let it impregnate the transformer, then let it dry, after drying repeat the process 2 times

Maybe you can also replace the original transformer with a Toroidal transformer

 

[guy_4]

Hello All,

I re-designed the power supplies on a H3000 ( 50Hz ) that was full of noise from vibrations of the PT to the chassis.
I removed the original PT, and a power resistor too.
One SMPS for digital. 5 V / 7 Amp. Ref : Meanwell LRS-35-5
One toroïdal transformer for the Audio. 2X15V - 30VA. Ref : VTX-146-030-215
A bit of metal work to install this new stuff, and some new wiring too.
I also cleaned the contacts of the Molex connector of the power supply.
Not any hum or vibration anymore, quiet as a mouse...

Best,
Guy

 

[etfy]

Hello All,

I re-designed the power supplies on a H3000 ( 50Hz ) that was full of noise from vibrations of the PT to the chassis.
I removed the original PT, and a power resistor too.
One SMPS for digital. 5 V / 7 Amp. Ref : Meanwell LRS-35-5
One toroïdal transformer for the Audio. 2X15V - 30VA. Ref : VTX-146-030-215
A bit of metal work to install this new stuff, and some new wiring too.
I also cleaned the contacts of the Molex connector of the power supply.
Not any hum or vibration anymore, quiet as a mouse...

Best,
Guy

Hi Guy, I see this is about 50€ of parts (if I got it right). I'm not familiar with electronics but I can follow schematics and know how to solder. Would you be able to share a rough wiring schematic? My H3000 is so loud it drives me crazy.

 

[guy_4]

Hi Guy, I see this is about 50€ of parts (if I got it right). I'm not familiar with electronics but I can follow schematics and know how to solder. Would you be able to share a rough wiring schematic? My H3000 is so loud it drives me crazy.

Hello etfy,

Not much more to tell you than I wrote previously !
AFAIR I did not draw any schematic.
If you need it, you can easily find the H3000 schematics on the internet. ( or on the Forum Library ? )

Original PS was designed with a PT that has one AC coil of 8...10 V , and also two AC 15V coils.
I replaced it with two separate units :
1/ One DC 5V supply from Meanwell, that I directly connected to the main board, for Logic IC's supply, bypassing the regulator and the power resistor on the side of the chassis.
I kept the filtering caps in place because they are hard to remove. ( under the board )
2/ Connect the wires of the new transformer ( for the +/_ 15VDC Audio supply ) in place of the wires that came from the coils of the original transformer.
I installed it on the side of the chassis.

The Ref that I listed are the exact ref. that I used, and easily available.
You will have to make a bit of metal work to install the new units in the chassis.
With a few hours and tools it will be easy to do. ( some screwdrivers, an electric drill, some screws, cutters, a soldering iron, some wires..)

Also I re-wired the H3000 mains for 230V AC, with voltage selector by-pass.

Best,
Guy