SSL 9K & 4K (E Series) 500 / 51X NEW BOARDS Mic Pre Thread 2011

[Ricardus]

Hi!

The caps with values in picofarads, ¿can be ceramics? (cog/npo). or must be wimas mkp/fkp?...

Just curious. Did you get the PDF parts list that Gustav has up on his google drive? It gives example part numbers for most of the parts, and from those numbers you can find alternatives if that particular part is out of stock.

 

[Whoops]

Hi!

The caps with values in picofarads, ¿can be ceramics? (cog/npo). or must be wimas mkp/fkp?...

those caps can be standard ceramics, cog/npo, polystyrene/styroflex, Wima or Panasonic.

all work well

 

[JAY X]

Hi!, Yes I read the Bom, but i was doubting too much...so i asked here..
Thanks for your advise!!

 

[Ricardus]

those caps can be standard ceramics, cog/npo, polystyrene/styroflex, Wima or Panasonic.

all work well

2.5 mm lead spacing right next to the IC sockets. MLCCs fit best.

 

[Manucas]

Just for information, the PCB v4.2 has still the out of phase problem.
I've built two of them, with PCB coming from Gustav at pcbgrinder (bought in 04/21), and when I trace with scope, IN (10) and OUT (2) are clearly out of phase, you need to engage the phase switch to have correct polarity.
So don't forget the fix given by bruno (attached pdf) . For my two units it's clearly better now... ;-)
Despite this small problem, it's a great sounding preamp, really !!

 

[Ricardus]

Just for information, the PCB v4.2 has still the out of phase problem.
I've built two of them, with PCB coming from Gustav at pcbgrinder (bought in 04/21), and when I trace with scope, IN (10) and OUT (2) are clearly out of phase, you need to engage the phase switch to have correct polarity.
So don't forget the fix given by bruno (attached pdf) . For my two units it's clearly better now... ;-)
Despite this small problem, it's a great sounding preamp, really !!

Can you upload a pic of your fix just so I can see it?

 

[Manucas]

Yes sure.

 

[Ricardus]

Yes sure.

Thanks.

 

[Bernardo]

hi everyone, i just finished assembling a ssl9k version 500 series and i have a lot of problems.I have followed the thread and everyone says that it is very easy and I think it is true, the assembly process is very clear and easy, it is the project that is costing me the most.First of all, I have to force my voice a lot to get audio from the mic to the preamp, the sound that comes in is very saturated and horrible, it backfires when I move a switch.I have measured the mat02 npn transistor and it seems to be fine, with a positive tip in the center, it measures the right and left pins the same, the two transistors coincide at 750.I have reviewed all the resistors and they are good in values.Could it be some inverted "BP" capacitor?could it be the tantalum capacitor?I can't measure the volts from the oamps because I don't have a 500 series extender.any ideas?Thank you very much and sorry for the long story.

 

[Bernardo]

I do not understand why they carry a symbol + those positions of electrolytic capacitors if they are BP, is it supposed that the position of these does not matter?

 

[Ricardus]

hi everyone, i just finished assembling a ssl9k version 500 series and i have a lot of problems.I have followed the thread and everyone says that it is very easy and I think it is true, the assembly process is very clear and easy, it is the project that is costing me the most.First of all, I have to force my voice a lot to get audio from the mic to the preamp, the sound that comes in is very saturated and horrible, it backfires when I move a switch.I have measured the mat02 npn transistor and it seems to be fine, with a positive tip in the center, it measures the right and left pins the same, the two transistors coincide at 750.I have reviewed all the resistors and they are good in values.Could it be some inverted "BP" capacitor?could it be the tantalum capacitor?I can't measure the volts from the oamps because I don't have a 500 series extender.any ideas?Thank you very much and sorry for the long story.

Please upload some hi-res pics of the top and bottom of this board.

 

[Bernardo]

Hi Ricardus!here mis pics.

 

[Bernardo]

I think I know where the fault is, I have put ceramic capacitors instead of polyester film capacitors, could that be why it distorts so much ??

 

[Ricardus]

You said you used a MAT02 transistor but I see what looks like an LM394, which should also be fine. But did you test the transistor with a proper transistor tester before you installed it?

 

[Bernardo]

You said you used a MAT02 transistor but I see what looks like an LM394, which should also be fine. But did you test the transistor with a proper transistor tester before you installed it?

Yes, I tested it, with a positive tip in the center, the right and left pin mark the same 750, the other side the same.I have tried with another lm394 and with two paired bc550c (I have a full bag), the result is the same, saturation and bursts, I have also changed the gain potentiometer, it did not work either, I have checked all the values of the resistors 3 times andNothing, tomorrow when I get the polyester film capacitors I will change them for the ceramic ones to see what happens ......

 

[Bernardo]

Well, after changing the ceramic condensers for polyester film, change all the oamp except that1646, change the lm394, check all the resistors 3 times to verify that all the values are correct, my unit remains the same, input with saturated viz and apneumatic hammer type oscillation.Can someone advise me something, I don't know what to do ...Thank you

 

[Ricardus]

Well, after changing the ceramic condensers for polyester film, change all the oamp except that1646, change the lm394, check all the resistors 3 times to verify that all the values are correct, my unit remains the same, input with saturated viz and apneumatic hammer type oscillation.Can someone advise me something, I don't know what to do ...Thank you

Is that when the HPF is switched on or off?

 

[grid_stopper]

I dont think blindly swapping parts is going to do you much good here. It would be worth your while to get a 500 series extender, and put together a cheap audio probe if you dont have an o-scope so you can really narrow down where the problem is coming from. this will save you a lot of headache and guesswork

 

[Bernardo]

I made my measurements the tl052 has: pin 4 -16 pin 8 +16 that 1646 pin5 -16 pin6 +16 ne5534 pin4 -16 pin 7 +16except ic22 ic29 pin2 +15 pin3 +11 pin4 -16 pin6 -0.5v pin 7 +16 all very close to the scheme.

the drill sound is always,

 

[grid_stopper]

I made my measurements the tl052 has: pin 4 -16 pin 8 +16 that 1646 pin5 -16 pin6 +16 ne5534 pin4 -16 pin 7 +16except ic22 ic29 pin2 +15 pin3 +11 pin4 -16 pin6 -0.5v pin 7 +16 all very close to the scheme.

the drill sound is always,

measuring voltage is important, but im talking about using an audio probe here. pump a test tone through the input, attach it to different points in the audio path, and find out where the noise starts-that will tell you where to start.