[BUILD] 1176LN Rev D DIY

[moelli]

I´m doing my first diy project using the hairball enclosure and the Mnats pcbs , 1176LN Rev: D Version 2, following the Instruction and schematics on Mnats Site.
During the project I have a Couple of Questions, and I would be glad to your experiences and practical knowledges to fix it………

1. Scale on Hairball frontpanel / In and Out pots
I mounted the potentiometers and the knobs, but  the scales on input and output  does not fit with the pots or vice versa . If I mount the Knobs with the line on "0" (fully CCW) and turn it to fully CW, the end point is reached @ -3 db (and not @ 0dB, as it should be). I try to attch two photos to illustrate this problem.

http://www.gastronix.de/doc/fully-ccw.jpg
http://www.gastronix.de/doc/fully-CW.jpg

Mike from Hairball told me,  this is normal, because he uses the front design from the UREI , what is designed for 320 degree rotation.  Today this 320 degree pots for IN and OUT, (Attenuator and Pot) seem to be hard to find……

I´m using this Input Attenuator from Hairball http://hairballaudio.com/shop/product_info.php?cPath=22&products_id=54

and the output pot from Mouser using the Hairball Cart Link:

http://de.mouser.com/ProductDetail/Alpha-Taiwan/RV24AF-10-15R1-A250K/?qs=sGAEpiMZZMtxdMMi52izyqQd5VRNGCmWyudJCKsapxw%3d

Does anybody have an Idea to solve this problem?  How did you mounted the Knobs on your project (line at CW or CCW), are there possible problems in with a view to calibration ?

2. Transistors 2N3707
On Mnats schematic and on the PCB are 3707, following the Mouser Cart Link I got 2N3708.
As I`ve seen, Mouser can deliver 3707, what´s the reason to change it ? The main difference between 3707 & 3708 seems to be, that the 3707 is a “low noise” version…….

3. Calibration: Looking forward I have to calibrate my 1176´s, some of Mnats calibration videos are hard to understand, (because English is not my main language ….) Is there anywhere a complete written instruction for the calibration?

Thank you all for your help.

Kindly Regards

Jens

 

[Hank Dussen]

1. Scale on Hairball frontpanel / In and Out pots
I mounted the potentiometers and the knobs, but  the scales on input and output  does not fit with the pots or vice versa . If I mount the Knobs with the line on "0" (fully CCW) and turn it to fully CW, the end point is reached @ -3 db (and not @ 0dB, as it should be). I try to attch two photos to illustrate this problem.

http://www.gastronix.de/doc/fully-ccw.jpg
http://www.gastronix.de/doc/fully-CW.jpg

Mike from Hairball told me,  this is normal, because he uses the front design from the UREI , what is designed for 320 degree rotation.  Today this 320 degree pots for IN and OUT, (Attenuator and Pot) seem to be hard to find……

I´m using this Input Attenuator from Hairball http://hairballaudio.com/shop/product_info.php?cPath=22&products_id=54

and the output pot from Mouser using the Hairball Cart Link:

http://de.mouser.com/ProductDetail/Alpha-Taiwan/RV24AF-10-15R1-A250K/?qs=sGAEpiMZZMtxdMMi52izyqQd5VRNGCmWyudJCKsapxw%3d

Does anybody have an Idea to solve this problem?  How did you mounted the Knobs on your project (line at CW or CCW), are there possible problems in with a view to calibration ?

This is purely an aesthetical problem. You decide. FWIW, I lined them at the minus infinite, because I guess you'll more often turn the input and output completely CCW then completely max.

2. Transistors 2N3707
On Mnats schematic and on the PCB are 3707, following the Mouser Cart Link I got 2N3708.
As I`ve seen, Mouser can deliver 3707, what´s the reason to change it ? The main difference between 3707 & 3708 seems to be, that the 3707 is a “low noise” version…….

There IS a reason for the 2N3708's. I forgot about it but I'm sure it's somewhere in this threat.

3. Calibration: Looking forward I have to calibrate my 1176´s, some of Mnats calibration videos are hard to understand, (because English is not my main language ….) Is there anywhere a complete written instruction for the calibration?

Check the info here: http://www.gyraf.dk/gy_pd/1176/1176.htm
And the info in the original manual: http://mhumhirecords.org/DIYpages/1176/urei_1176ln.pdf
Combined with the videos, you should be able to fix it.
I did have to change R75 to a 5K trimmer (instead of 2K) on one of my build to get the meter to null properly.
You might want to go for that, just to make sure.

 

[kosty]

1. Scale on Hairball frontpanel / In and Out pots
I mounted the potentiometers and the knobs, but  the scales on input and output  does not fit with the pots or vice versa . If I mount the Knobs with the line on "0" (fully CCW) and turn it to fully CW, the end point is reached @ -3 db (and not @ 0dB, as it should be). I try to attch two photos to illustrate this problem.

http://www.gastronix.de/doc/fully-ccw.jpg
http://www.gastronix.de/doc/fully-CW.jpg

Mike from Hairball told me,  this is normal, because he uses the front design from the UREI , what is designed for 320 degree rotation.  Today this 320 degree pots for IN and OUT, (Attenuator and Pot) seem to be hard to find……

I´m using this Input Attenuator from Hairball http://hairballaudio.com/shop/product_info.php?cPath=22&products_id=54

and the output pot from Mouser using the Hairball Cart Link:

http://de.mouser.com/ProductDetail/Alpha-Taiwan/RV24AF-10-15R1-A250K/?qs=sGAEpiMZZMtxdMMi52izyqQd5VRNGCmWyudJCKsapxw%3d

Does anybody have an Idea to solve this problem?  How did you mounted the Knobs on your project (line at CW or CCW), are there possible problems in with a view to calibration ?

That's normal. Just align it to - infinite.

2. Transistors 2N3707
On Mnats schematic and on the PCB are 3707, following the Mouser Cart Link I got 2N3708.
As I`ve seen, Mouser can deliver 3707, what´s the reason to change it ? The main difference between 3707 & 3708 seems to be, that the 3707 is a “low noise” version…….

It's easier to find a 3708 within the right range than a 3707.

3. Calibration: Looking forward I have to calibrate my 1176´s, some of Mnats calibration videos are hard to understand, (because English is not my main language ….) Is there anywhere a complete written instruction for the calibration?

Watch these videos again and again. The only difference you should note is that every time he says to short 22 to ground you just have to turn your attack knob to OFF.

 

[kosty]

Somebody can help me with this ?

I've got some hum / noise issues after doing some changes on the board and I just can't find what is causing this.
The unit was fine before.
So what I did is :

I removed the sockets for Q1, Q11, Q12, Q13 and soldered them back directly on the board in the same position.
I did the same for R59 (Q-Bias pot) after placing a socket there because of a faulty pot previously.
I resoldered XLR in / Out (just cut out the end of the previous cable and resoldered it in a cleaner way then before).
Grounded the input transformer board, as the tutorial of mnats suggests.

The problem now is that I have noise (ssshhhhhhhhh) going to the output if I turn the output level above 9 o'clock and some hum is added above the 12 o'clock position.

It appears that it's not related to the Input or the input att / tranny, because this problem remains after removing the wires to the input section of the board.

The strange thing about the hum is, that it gets louder when I hold my hand close to the pcb board (approx 2-3cm).

Is it possible that I can get these symptoms when Q1, Q11, Q12 or Q13 are not soldered correctly or the pins are shorted  ?

I forgot to mention that I also switch the red / blue wire of the output xformer to the output.

 

[blackwaterstudios]

I believe I figured it out - square wave worked fine, thanks all it's working like a charm!  Idiot wired the ratio board backwards so pressing 20:1 gave me 4:1.  Just gotta figure out how he did that and reverse it.

 

[moelli]

Today I finished my first 1176, and now I got a problem. My unit is oscillating in relation to the output pot. I checked all the wires, seems to be ok, and now I don´t know how to fix it......
The input signal is passing the unit, the needle of the VU meter is (switched @ 4) hard on the right side........
If you got any suggestions, or ideas, I would be glad, If you could help me. I link a couple of Photos and a wave-file, where you can hear this sound, when I turn the output pot from CCW to CW and back.

Thank you all for some help

best regards

Jens
http://www.gastronix.de/doc/turning output from CCW to CW and back.wav
http://www.gastronix.de/doc/1176-1.jpg
http://www.gastronix.de/doc/1176-2.jpg
http://www.gastronix.de/doc/1176-3.jpg
http://www.gastronix.de/doc/1176-4.jpg
http://www.gastronix.de/doc/1176-5.jpg

 

[kosty]

Today I finished my first 1176, and now I got a problem. My unit is oscillating in relation to the output pot. I checked all the wires, seems to be ok, and now I don´t know how to fix it......
The input signal is passing the unit, the needle of the VU meter is (switched @ 4) hard on the right side........
If you got any suggestions, or ideas, I would be glad, If you could help me. I link a couple of Photos and a wave-file, where you can hear this sound, when I turn the output pot from CCW to CW and back.

Thank you all for some help

best regards

Jens
http://www.gastronix.de/doc/turning output from CCW to CW and back.wav
http://www.gastronix.de/doc/1176-1.jpg
http://www.gastronix.de/doc/1176-2.jpg
http://www.gastronix.de/doc/1176-3.jpg
http://www.gastronix.de/doc/1176-4.jpg
http://www.gastronix.de/doc/1176-5.jpg

I've also got some oscillation when the output is near max.
Without any Input signal (and input level turned fully down) the meter jumps suddenly to the hard right if reaching some kind of threshold near the output max level.

Also very bizarre is that in GR Meter mode the meter exceeds 0 db when output level is max.

My oscillation is slower than yours (approx. 4 hz).
I'm sure it has something to do with a grounding / shielding issue.

 

[Futureman]

I had the same problem with oscillation..

It cleared up when I changed my adjusted my grounding wires. (In my case, the ones on the XLR's)

Best of luck.

Mike

 

[kosty]

I was able to isolate my problem with the oscillation.
There is some kind of short if I connect both XLR pin 2 and pin 3 to the output tranny.

The Unit is working normally if I only connect XLR pin 3 (cold) to the red wire of the output transformer.
As soon as I connect the blue wire I get hum, noise and oscillation.

If I touch Q6 (round transistor with the heat sink) I have some buz on the output. Is this normal ?
Can someone please test this on his device ?

Thank you

 

[moelli]

I found my failure (I should solder C 15 correctly) , but now I have problems to calibrate the unit.

All the steps in Video 1 and Video 2 from Mnats I did as shown in the videos and to this step it seems to be alright.

But when I try to follow the instructions in Video 3 I´m not able to set the levels for 0db without GR an -10db with GR. When I turn the output to 0dB without GR, I got with  GR  a level of -13 dB.
When I turn now  the Input pot (stands at 12 clock) more to CW , I have with GR On 1dB more to CW on the complete second half of the pot way. With GR off the Output is overloaded and the needle of the VU meter is hard right……..
It seems, there  is a wrong setting  of some adjustments, but I still don´t know, what`s wrong. 

I worked with a  Ratio of 20, when I use a Ratio of 4 , I still can set the levels as related in Video 3.

Should there be a wiring issue to the ratio-Board, or the Resistors on Ratio board are not correct soldered ?

Seems to be not usefull . With a Ratio of 4 I got more compression than on 20……

Thanks for your tips and ideas.

Kindly Regards

Jens

 

[jandoste]

But when I try to follow the instructions in Video 3 I´m not able to set the levels for 0db without GR an -10db with GR. When I turn the output to 0dB without GR, I got with  GR  a level of -13 dB.
When I turn now  the Input pot (stands at 12 clock) more to CW , I have with GR On 1dB more to CW on the complete second half of the pot way. With GR off the Output is overloaded and the needle of the VU meter is hard right……..
It seems, there  is a wrong setting  of some adjustments, but I still don´t know, what`s wrong. 

I worked with a  Ratio of 20, when I use a Ratio of 4 , I still can set the levels as related in Video 3.

Should there be a wiring issue to the ratio-Board, or the Resistors on Ratio board are not correct soldered ?

Seems to be not usefull . With a Ratio of 4 I got more compression than on 20……

Thanks for your tips and ideas.

Kindly Regards

Jens

Got the problem ! since long time ) GR is not work  for me

 

[Echo North]

You shouldn't be touching the input pot when making the adjustment.

I haven't done the calibration in a while, but sometimes it helps to use a 5K trim pot instead of a 2K in the tracking adjust position. 

 

[moelli]

GR works for me, but not as i should.
I checked the function again, an I have @ Ratio 4 a larger compression than @ Ratio 20....
I checked the wiring of the meter board, everings is right, so I have to check the Ratio board again.
I used this table for the resistors:
http://hairballaudio.com/docs/FET_Compressor_PCB_Board_Info_V2.pdf
Hope that was usefull.
It feels like the resistors on the Ration board are soldered in wrong direction.
If anybody got a unit, which is working fine, I´d like to verify the ratio board ......

Thanks for any help or  idea.

Jens

 

[Echo North]

GR works for me, but not as i should.
I checked the function again, an I have @ Ratio 4 a larger compression than @ Ratio 20....
I checked the wiring of the meter board, everings is right, so I have to check the Ratio board again.
I used this table for the resistors:
http://hairballaudio.com/docs/FET_Compressor_PCB_Board_Info_V2.pdf
Hope that was usefull.
It feels like the resistors on the Ration board are soldered in wrong direction.
If anybody got a unit, which is working fine, I´d like to verify the ratio board ......

Thanks for any help or  idea.

Jens

This is normal.

The threshold is lower at 4 than at 20 so you see more compression on the meter at lower ratios.

What is different is the RATIO.  How much compression is being applied vs the input signal.  You can read how to measure that here:
http://www.axtsystems.com/index.php?option=com_content&view=article&id=54:1176lnratios&catid=34:1176ln&Itemid=62

Sounds like yours is working as i should.

Mike

 

[moelli]

I don´t think so, cause I can´t set (see my reply from yesterday) the parameters for callibration Video 3 with Ratio 20
(0db level witout GR, -10db with GR)
When I set RAtio to 4 , this parmeters are possible

All the steps in Video 1 & 2 I did correct.

Why does it not work for the steps in video 3 ?

Thanks Jens

 

[moelli]

Now I used another calibration guide, this one, http://www.axtsystems.com/index.php?option=com_content&view=article&id=56:1176lncalibration&catid=34:1176ln&Itemid=62
and everything should be ok, the unit works and I´ll try the one this weekend @ my studio.

A last question results , when I have a look to the IN/Out Levels.

With Odb input, no GR,  and the VU@0 I should have a output Signal with 0dB ?
With meter Switch @ 4 I have a output signal of -8 db, seems not to be correct,

Is there a possibility to get the parmeters correct ?
(0dB Input, 0db at the meter and 0 dB on the Output ?

Thanks for your Ideas

Jens

 

 

[Majestic12]

I've got a problem with step 3 of the calibration procedure. I can't observe any signal drop when turning on the gain reduction. I already checked the switch on the attack pot but it is working perfectly. Does anybody know what's wrong? This is my second 1167 Rev D build, and the first one works perfectly...

 

[ShandonSound]

Hi,
I got my replacement meter from Hairball (having had the bad luck to receive a dead one!). Many thanks to Hairball for sorting this so quickly, and without hesitation, for me.

I've now completed the calibration process and everything seems to be working but I'm not at all sure I've got things right!
When I apply a 1khz test tone to the input and set the output to read 0Vu it comes into my DAW at about -18db(fs)  which seems about right(?). When I plug in another 'real world' source, however, such as the output of a mic pre the VU meter hardly moves, even when I set the output of the mixer/mic pre to be peaking around -18db/0Vu. The GR seems to be metering as I would expect and it sounds good. More worrying though when applying a 1khz signal if I switch to +8db on the meter select switches the output level drops a couple of db, I don't think this should happen should it?

Although I've gone through the calibration process and got the right readings I didn't feel that confident about using the trimmers. I've searched for some basic advice on this with no luck; I don't really understand how you set them fully CCW or CW as they just seem to turn infinitely- where's the reference point? Frankly, I'm embarrassed to ask but some basic advice would be very welcome!

Many thanks in advance if anyone can spare the time to offer some advice.

Steve

 

[Majestic12]

Have another strange problem. I openend both my 1167 and tightened all the pot screws (not too tight). After that, both units refuse to work properly. Signal is passing through but the gain reduction does not work any more (cant hear any compression going on and neither read something on the meter set to GR). Don't know what to do now. I loosened the screws again, but nothing happens....

I can do the calibration process on each unit with success but the compression won't get to work any more. I' totally lost now, same problems on both units....

 

[SaMpLeGoD]

Have another strange problem. I openend both my 1167 and tightened all the pot screws (not too tight). After that, both units refuse to work properly. Signal is passing through but the gain reduction does not work any more (cant hear any compression going on and neither read something on the meter set to GR). Don't know what to do now. I loosened the screws again, but nothing happens....

I can do the calibration process on each unit with success but the compression won't get to work any more. I' totally lost now, same problems on both units....

Wich pots are you using? I experienced some problems like that in PEC pots... if you're using ALPHA ones, try to measure if they're working propertly... if yes, you unfortunately have some wiring issue...check it out again.
Cheers,
Eddie