8 Channel, 3U NEVE 1073 completed

[dude24man]

chrome, no scope here right nowm, whats the best way to bias using a volt meter? arty

 

[Chrome Heart]

chrome, no scope here right nowm, whats the best way to bias using a volt meter? arty

Just follow Martins "field solution" of 22.6V from the case of the 2N3055 to 0V. But I would highly recommend getting a scope. If your doing the DIY there is no reason not to have one. Its an essential tool, and you can get them pretty cheap if you look around. I found mine at a yard sale for 25.00.

 

[leitrim_lad]

Hi there, just one more quick question about how hot these should be as in gain wise.., i sorted out the moise problem on my 2nd channel and its back working, also had a problem with 48v on 1st channel and got that sorted to.. Just wondering about gain.. what are the different gain stages on the switch? if i plug in a standard sm58 its clipping by the time i turn the switch to the 5th position.. is this normal or is it WAY to hot? also if i have nothing plugged into the unit and put the gain up full i hear a hi pitch noise from the board itself.. is this normal? Thanks in advance

 

[Chrome Heart]

Hi there, just one more quick question about how hot these should be as in gain wise.., i sorted out the moise problem on my 2nd channel and its back working, also had a problem with 48v on 1st channel and got that sorted to.. Just wondering about gain.. what are the different gain stages on the switch? if i plug in a standard sm58 its clipping by the time i turn the switch to the 5th position.. is this normal or is it WAY to hot? also if i have nothing plugged into the unit and put the gain up full i hear a hi pitch noise from the board itself.. is this normal? Thanks in advance

No, thats not normal. I accidentally had a 1.8k resistor in a position for an 18k and had a similar problem on an earlier build. I would guess its a component error. (Is the locating pin on the Grayhill in the right spot?) Remember to wait until after the soldering iron is off to open the beers. Its nice to enjoy a frothy beverage while building, but it can cause some problems.

 

[leitrim_lad]

i didnt build it so im presuming the pin would be in the right spot.. ive the same gain off both cards tho so whatever it is its on both cards.. is clipping an sm58 wen the switch is turned to position 5 FAR to hot?

 

[Chrome Heart]

Well, those are 5db steps of gain, so your hitting it pretty hard. Try putting a -10 or -20db pad inline and see what it sounds like. I use a go-between on my builds because sometimes the source mic has way too much input gain. Not so with the ribbons though, they work great.
I also missed that you said you "had the gain all the way up" when you heard the noise. I would think thats normal. The transformers are probably oscillating at that gain setting. At that point your hitting with 75db of input. You also need to bias the unit if you havent done so.

 

[leitrim_lad]

so id be hitting it at 45db of gain.. would it be normal so to clip (just barely) with an sm58 at 45db of gain? yep must get a gobetween for it.. was planning to for the phase anyway.. i biased it with a ddm meter.. dont have a scope. gonna try get the loan of one tho,, thanks a million

 

[muffy1975]

Hi there,

has anyone used an OEP A262A3E with EZ1290?

If so, how do you wire this thing as a replacement for the more expensive carnhill?

If this has already been discussed please point me in the right direction. I have searched a found nothing.

thanks

Michael

 

[desol]

Primaries in parallel and secondaries in parallel.

http://www.oep.co.uk/pdf/A262A3E.pdf

 

[leitrim_lad]

Hey just a quick, probably stupid question, im wondering could u help me with. iv completed my pres and everything is working perfect. ive wired them up to a patch bay and when i got straight from the pres through the patchbay into the converter everything is perfect but when i go out of the pres into the patch bay into a compressor and into the converters i lose practically all signal.. It sounds very thinny and has no volume.. Any ideas what might be wrong? It happens with any compressor i plug it in to and iv tried other pres into the compressors and they work perfect..

Thanks in advance

 

[sr1200]

Is your patch bay set up correctly?
What type of compressor?
Does the compressor have a "mix or parallel" function.
Take the bay out of the equation and go direct from one unit to another.  See if that helps.

 

[Harpo]

...i lose practically all signal.. It sounds very thinny and has no volume...

Transformer balanced operation has signal swinging between XLR-pins2/3 exclusivly. XLR-pin1 is only shield, not related to audio signal. For unbalanced operation link XLR-pins1/3, preferably in the cable to or from the unit. YMMV.

 

[dude24man]

does any one have a 1u front panel for the ez1290 they want to sell? arty

 

[mikerl]

i have a JLM power station that i am using to power 4 ez1290's.  i recently moved the power station from inside the chassis, to an external enclosure (at the same time, i switched to an avel lindberg toroidal transformer).  i seem to be getting a reading, on every single regulator, when i check to ensure there is no continuity between it (the regulator plate), and the chassis (for heat sinking).  the reading that i am getting changed when i turned the trim pot at the base of the respective regulator..  is there a chance that i am reading a path to ground through another path, and that i actually do not have a short on every single regulator to the heat sink?


thanks..

mike

 

[Chrome Heart]

i have a JLM power station that i am using to power 4 ez1290's.  i recently moved the power station from inside the chassis, to an external enclosure (at the same time, i switched to an avel lindberg toroidal transformer).  i seem to be getting a reading, on every single regulator, when i check to ensure there is no continuity between it (the regulator plate), and the chassis (for heat sinking).  the reading that i am getting changed when i turned the trim pot at the base of the respective regulator..  is there a chance that i am reading a path to ground through another path, and that i actually do not have a short on every single regulator to the heat sink?


thanks..

mike

If you had a short between the regulator and the case you would know it immediately because the regulator would more than likely burn. Check for 10ohms resistance between the 0V and the case. If that checks out chances are all is good, provided the JLM is assembled correctly.

 

[Chrome Heart]

Is your patch bay set up correctly?
What type of compressor?
Does the compressor have a "mix or parallel" function.
Take the bay out of the equation and go direct from one unit to another.  See if that helps.

It sounds to me like you have something phased incorrectly. I run my patchbay balanced 1-1, 2-2, 3-3 with no problems.

 

[mikerl]

i have a JLM power station that i am using to power 4 ez1290's.  i recently moved the power station from inside the chassis, to an external enclosure (at the same time, i switched to an avel lindberg toroidal transformer).  i seem to be getting a reading, on every single regulator, when i check to ensure there is no continuity between it (the regulator plate), and the chassis (for heat sinking).  the reading that i am getting changed when i turned the trim pot at the base of the respective regulator..  is there a chance that i am reading a path to ground through another path, and that i actually do not have a short on every single regulator to the heat sink?


thanks..

mike

If you had a short between the regulator and the case you would know it immediately because the regulator would more than likely burn. Check for 10ohms resistance between the 0V and the case. If that checks out chances are all is good, provided the JLM is assembled correctly.

thanks for chiming in!  i have not yet powered it up, because of this discrepancy.  is there another way for me to make sure i dont have continuity here?


SO, i looked at the schematic, and it appears that the regulators go to ground through the trimmer.. and at this point, the pcb is connected to ground through the mounting eyelets on one of the 4 corners  via c21 and r14.  SO, in odered to get a correct reading of in-continuity between the case and the regulators, wouldn't i have to remove the 4 mounting screws?

should i be using non-conductive mounting screws?

 

[dude24man]

you could try another power supply? power one hb24 or bigger (ebay cheap) comes to mind. just for testing. arty

 

[mikerl]

not sure i understand.

this supply works, and has in the past, but i mounted it in a new case, and im wondering about the continuity between the case and the regulators.

 

[Chrome Heart]

not sure i understand.

this supply works, and has in the past, but i mounted it in a new case, and im wondering about the continuity between the case and the regulators.

Just put one probe on the screw thats holding the regulator to the case, and the other on the case. If you have continuity it will burn. The mounting screw should NOT be contacting the PS case.