8 Channel, 3U NEVE 1073 completed

[sr1200]

the JLM add on (which i have on all 6 of my pres) doesn't have an impedance selection. :-\ :'(

 

[sam system-d]

Don't be sad, just take the input transfo pcb, a switch, and it's done 

 

[rokus666]

I would like to start a 4 channel project.

will collective cases 4 channel 2RU work with this one?

 

[sam system-d]

I don't know, everytging I make is all custom (except the EZ1290 main board).
You can easely draw a drill mask out of it and see if it can fit. If not, just use switches and wires them without the switch pcb.

 

[sr1200]

Id really appreciate a schematic for this.  I thought there was already input impedence on the main board so wouldn't you have to bypass that or put this in place of?

 

[sam system-d]

I think impedance depends on the way you wire the input transfo. 3 and 4 together or 2 and 3 , and 4 and 5. So no such thing can be already on the board. Go back few pages before, + posted that on pdf. The 48/pol/pad schematic is based on fabio's replica 312. 8ack home, +'ll post this.

 

[sam system-d]

Here it comes.
Transfo infos can be found here :
Reply #1043

 

[sr1200]

ok so then the switch connected to the trafo will determine the connection thus determining weather it is 300 or 1200 ohms

 

[sam system-d]

Actually, the switch commands the relay, and the relay determines the connections.
As this particular project is sensitive to noise and you have to use shield wire everywhere, I thought that keeping the relay next to the transformer was better for he signal. Mitsos gaveme this idea on page 53.

 

[mitsos]

hey nice!  I ended up doing the impedance thing the same way, no pad though, just polarity, 48V, and impedance. 

 

[atticmike]

will be putting my neve / ssl box together by this weekend with the jlm powerstation v3.

just to keep the other transformers for my eq racking, I'd love to know whether I can still use the 22 v transformer from the manual that I bought and thought it was a complete waste since the preamp runs at 24v? (european 230v)

TE62085-ND: http://www.digikey.com/product-detail/en/62085-P2S02/TE62085-ND/299881

*edit* Does it have to do with the capacitors powering up such as 22v * 1.414?

 

[desol]

Feed the powerstation what it wants...24vac to 30vac.

Edit: actually, joe has a new spec on his powersupply. Apparently 15-30vac now...so you should be ok as long as you have version 3...i guess.

http://www.jlmaudio.com/shop/index.php?_a=viewProd&productId=12

 

[atticmike]

Feed the powerstation what it wants...24vac to 30vac.

Edit: actually, joe has a new spec on his powersupply. Apparently 15-30vac now...so you should be ok as long as you have version 3...i guess.

http://www.jlmaudio.com/shop/index.php?_a=viewProd&productId=12

nah, rather talking about 24v the pre needs but still being able to power it properly with just 22v secondary since the capacitors load up and with its saturation  level out the gaps?

 

[desol]

Feed the powerstation what it wants...24vac to 30vac.

Edit: actually, joe has a new spec on his powersupply. Apparently 15-30vac now...so you should be ok as long as you have version 3...i guess.

http://www.jlmaudio.com/shop/index.php?_a=viewProd&productId=12

nah, rather talking about 24v the pre needs but still being able to power it properly with just 22v secondary since the capacitors load up and with its saturation  level out the gaps?

Well, you have to feed the powerstation v2(24-30vac) and v3(15-30vac) then it's rectified, filtered, etc to your adjustable DC voltage...so whatever AC input voltage it wants, is what you need to give it. You have 22vac...so if you have a version 2 powerstation, that's not enough. Or, consult Joe about it...

 

[atticmike]

Feed the powerstation what it wants...24vac to 30vac.

Edit: actually, joe has a new spec on his powersupply. Apparently 15-30vac now...so you should be ok as long as you have version 3...i guess.

http://www.jlmaudio.com/shop/index.php?_a=viewProd&productId=12

nah, rather talking about 24v the pre needs but still being able to power it properly with just 22v secondary since the capacitors load up and with its saturation  level out the gaps?

Well, you have to feed the powerstation v2(24-30vac) and v3(15-30vac) then it's rectified, filtered, etc to your adjustable DC voltage...so whatever AC input voltage it wants, is what you need to give it. You have 22vac...so if you have a version 2 powerstation, that's not enough. Or, consult Joe about it...

now I get it

no it's fine, got the v3

 

[orangechili]

Hey guys,

I have a dual channel 1290 here that has one channel humming and has a thin output, no low end.  I've built up a number of these, but have never encountered something like this.  I've scoured the thing for hours on end, checked solder joints etc.  Any clue where to look for what might be wrong?

Thanks!
Sig

I have basically a similar issue on a single channel 1290 build, there's no hum but a little less output and lack of low end. It was working well before but something apparently happened. I changed out all transistors(they're socketed) and still same problem. 2n3055 collector voltage is still 22.6v which is normal. I don't have a scope yet unfortunately. I know the input transformer was mentioned as a possible issue but don't have any extra here to swap out. Is there anything else I should check before forking out the cash for another input transformer? Any help in figuring this out is greatly appreciated!

 

[orangechili]

OK, Awesome! It was just a loose wire on the output xlr connection. I must have missed that on first inspection, very happy that's all it was ;D

 

[atticmike]

Feed the powerstation what it wants...24vac to 30vac.

Edit: actually, joe has a new spec on his powersupply. Apparently 15-30vac now...so you should be ok as long as you have version 3...i guess.

http://www.jlmaudio.com/shop/index.php?_a=viewProd&productId=12

nah, rather talking about 24v the pre needs but still being able to power it properly with just 22v secondary since the capacitors load up and with its saturation  level out the gaps?

Well, you have to feed the powerstation v2(24-30vac) and v3(15-30vac) then it's rectified, filtered, etc to your adjustable DC voltage...so whatever AC input voltage it wants, is what you need to give it. You have 22vac...so if you have a version 2 powerstation, that's not enough. Or, consult Joe about it...

So with the powerstation v3 and the 22 vac mentioned transformer, the one from the assembly documentation, I can smoothly run four neves?

 

[desol]

Yeah, that should be fine. Powerstation with the 6amp bridge rectifier will give you 1.5 amps on the + rail.
1.5 /4 gives you 375 mA each.

 

[atticmike]

what am I actually supposed to do with the jumper?