[BUILD] 1176LN Rev D DIY

[core64]

Stupid question of the day...  it's regarding the 22 AWG colored wire that comes with the Hairball 1176 Rev D kit. 

Question...  is all the colored 22 AWG wire the same, and just colored for reference, or is there some electrical differences between the colors?

I ask because the the lengths I cut for the yellow, orange and white wires that connect the 'zero adjust' pot to the pcb are a bit short.  I do have extra 22AWG wire that will work, but they are different colors.

Thanks in advance!

Electrically Challenged in Boston

 

[core64]

Stupid question of the day...  it's regarding the 22 AWG colored wire that comes with the Hairball 1176 Rev D kit. 

Question...  is all the colored 22 AWG wire the same, and just colored for reference, or is there some electrical differences between the colors?

I ask because the the lengths I cut for the yellow, orange and white wires that connect the 'zero adjust' pot to the pcb are a bit short.  I do have extra 22AWG wire that will work, but they are different colors.

Thanks in advance!

Electrically Challenged in Boston

Please disregard...  I tested it out and answered my own question.  You can use any colors.

Thanks

 

[core64]

I completed the Hairball rev d build and all seems to have gone well with the first three calibration tests but I just want make sure I had my signal generator correctly configured.

I have the signal generator plugin found in pro tools running to the xlr input of the 1176. With my 1176 input at 24...  I dropped the 1khz signal to -8.5dbfs. This allowed me to keep the 1176 input knob at 24 and obtain a .775 vac input value.

This allowed me to properly go through the three calibration steps correctly.

Does dropping the dbfs to -8.5 sound about right for this approach in calibration?

Thanks,

 

[core64]

Does dropping the dbfs to -8.5 sound about right for this approach in calibration?

I'm sooo close... (Hairball Rev D Build)

Ok, I'm assuming my calibration question in my last post is correct based on the fact the unit seems to be working correctly.  It's definitely compressing as I can here a clear audible difference as well as see the results in the gain reduction meter.  More important, I'm getting the sonics I would expect from the 1176 at the varying degrees of compression. 

I can also hear a clear audible difference when using the release knob.  The sound gets more open as I increase the release time (clockwise), and tighter if I decrease the release time (counter-clockwise).

The Issue:
All seems to be working perfectly fine except for two things...

• Attack
  The attack does not seem to work correctly.  I can successfully turn gain reduction off by turning the attack knob fully counter-clockwise to off, but hear no audible difference when trying to increase the attack time (clockwise) or decrease it (counter-clockwise).

• Ratio Buttons
  I hear no audible difference between all four ratio settings.  I can hear the brief change/adjustment you normally hear when hopping from one button to the other, but the gain reduction settles back to the same sonic state as well as from a metering standpoint.

I triple checked the wiring and feel confident it's correct.  Also inspected the solder joints and connections on the ratio pcb.  All connections and soldering seem extremely clean (no bridges etc).

Questions
Are there any specs I can measure to prove or disprove the ratio buttons are connected correctly?  One strange thing I found is that when measuring the ohms of the resistors on the ratio pcb board, they all appear a bit off from what they should be.  The all fall in their respective Ohm reading, but they're off a bit more than when I originally measured them, when installing them.  Is that because the pcb board is installed and connected to the main pcb and attack pot, and the readings differ after they're installed?

I'd totally appreciate any guidance in which steps I should take into troubleshooting this.

Thanks in advance!

Kenny

 

[dbonin]

• Ratio Buttons
  I hear no audible difference between all four ratio settings.  I can hear the brief change/adjustment you normally hear when hopping from one button to the other, but the gain reduction settles back to the same sonic state as well as from a metering standpoint.

Kenny

Unless you have super hearing you will not detect the difference! 

Put your DMM to measure AC volts on pin 2 and 3  of the output - apply your test signal, set attack to fastest setting, turn up the input to push the unit to trigger compression then cycle through the four ratios...  you should see  the voltage  DECREASE as you go from 20:1 (least compression) to 4:1 (most compression, lowest volts).

 

[dbonin]

• Ratio Buttons
  I hear no audible difference between all four ratio settings.  I can hear the brief change/adjustment you normally hear when hopping from one button to the other, but the gain reduction settles back to the same sonic state as well as from a metering standpoint.

Kenny

Unless you have super hearing you will not detect the difference! 

Put your DMM to measure AC volts on pin 2 and 3  of the output - apply your test signal, set attack to fastest setting, turn up the input to push the unit to trigger compression then cycle through the four ratios...  you should see  the voltage  DECREASE as you go from 20:1 (least compression) to 4:1 (most compression, lowest volts).

Also see this thread for a more precise test of output voltage after calibration:
http://groupdiy.com/index.php?topic=20058.msg708603#msg708603

Good luck!

 

[core64]

Unless you have super hearing you will not detect the difference! 

Put your DMM to measure AC volts on pin 2 and 3  of the output - apply your test signal, set attack to fastest setting, turn up the input to push the unit to trigger compression then cycle through the four ratios...  you should see  the voltage  DECREASE as you go from 20:1 (least compression) to 4:1 (most compression, lowest volts).
[/quote]

Also see this thread for a more precise test of output voltage after calibration:
http://groupdiy.com/index.php?topic=20058.msg708603#msg708603

Good luck!
[/quote]

Thank you very much for your response dbonin!!  I will test this tomorrow.

 

[core64]

Unless you have super hearing you will not detect the difference! 

Put your DMM to measure AC volts on pin 2 and 3  of the output - apply your test signal, set attack to fastest setting, turn up the input to push the unit to trigger compression then cycle through the four ratios...  you should see  the voltage  DECREASE as you go from 20:1 (least compression) to 4:1 (most compression, lowest volts).

Also see this thread for a more precise test of output voltage after calibration:
http://groupdiy.com/index.php?topic=20058.msg708603#msg708603

Good luck!
[/quote]

Hi Don,

I ran the two tests you suggested

Test 1  - Voltage Decrease
With my attack off, I ran my DAW's signal generator plugin into the 1176 at 1khz and measured 0.775 vac at the input and output as a baseline (I had to drop the signal generator to -8.5Dbfs to get 0.775).  I then turned the attack on fully cw and got the following results.  As you can see I'm definitely seeing a decrease in voltage as I toggle between the different ratio buttons.  I'm thinking that's good, right?

20 = 0.306
12 = 0.260
  8 = 0.241
  4 = 0.211


Test 2  - Output Voltage
I then followed the steps outlined in the link you sent, and received the following voltage readings at the output.  According to the link, does this mean I'm over compressing?

20 = 0.320
12 = 0.286
  8 = 0.280
  4 = 0.276

Thanks in advance Don!!

 

[core64]

Unless you have super hearing you will not detect the difference! 

Put your DMM to measure AC volts on pin 2 and 3  of the output - apply your test signal, set attack to fastest setting, turn up the input to push the unit to trigger compression then cycle through the four ratios...  you should see  the voltage  DECREASE as you go from 20:1 (least compression) to 4:1 (most compression, lowest volts).

Also see this thread for a more precise test of output voltage after calibration:
http://groupdiy.com/index.php?topic=20058.msg708603#msg708603

Good luck!

Hi Don,

I ran the two tests you suggested

Test 1  - Voltage Decrease
With my attack off, I ran my DAW's signal generator plugin into the 1176 at 1khz and measured 0.775 vac at the input and output as a baseline (I had to drop the signal generator to -8.5Dbfs to get 0.775).  I then turned the attack on fully cw and got the following results.  As you can see I'm definitely seeing a decrease in voltage as I toggle between the different ratio buttons.  I'm thinking that's good, right?

20 = 0.306
12 = 0.260
  8 = 0.241
  4 = 0.211


Test 2  - Output Voltage
I then followed the steps outlined in the link you sent, and received the following voltage readings at the output.  According to the link, does this mean I'm over compressing?

20 = 0.320
12 = 0.286
  8 = 0.280
  4 = 0.276

Thanks in advance Don!!
[/quote]

In addition...  I saw another test on here asking to measure the current going to some of the pads.  I tried this myself and got some really odd results

The test suggested the following...  "Feed a 1K 0dB signal into the compressor.  In/Out/Att/Rel all set half way. Confirm that you see 0.775 VAC between input pin 2 and 3."

AC voltage between pad 22 and ground:
20 - 0.420
12 - 0.201
8 - 0.120
4 - 0.054

AC voltage between pad 21 and ground:
20 - 0.001
12 - 0.001
8 - 0.001
4 - 0.001

AC voltage between pad 19 and ground:
20 - 0.001
12 - 0.001
8 - 0.001
4 - 0.001

As you can see, I'm getting zero readings at pads 21 and 19.

Any guidance or suggestions would be greatly appreciated!

Thanks!

k

 

[dbonin]

In addition...  I saw another test on here asking to measure the current going to some of the pads.  I tried this myself and got some really odd results

The test suggested the following...  "Feed a 1K 0dB signal into the compressor.  In/Out/Att/Rel all set half way. Confirm that you see 0.775 VAC between input pin 2 and 3."

AC voltage between pad 22 and ground:
20 - 0.420
12 - 0.201
8 - 0.120
4 - 0.054

AC voltage between pad 21 and ground:
20 - 0.001
12 - 0.001
8 - 0.001
4 - 0.001

AC voltage between pad 19 and ground:
20 - 0.001
12 - 0.001
8 - 0.001
4 - 0.001

As you can see, I'm getting zero readings at pads 21 and 19.

Any guidance or suggestions would be greatly appreciated!

Thanks!

k

Make sure you set your DMM to measure DC when testing pads 19 and 21

 

[core64]

Make sure you set your DMM to measure DC when testing pads 19 and 21

Ugh...  I missed that.  I'll spend some time this week going back and checking all of this stuff, ensuring I'm measuring correctly.

Thank you for your response Don!

 

[core64]

Unless you have super hearing you will not detect the difference! 

Test 1
Put your DMM to measure AC volts on pin 2 and 3  of the output - apply your test signal, set attack to fastest setting, turn up the input to push the unit to trigger compression then cycle through the four ratios...  you should see  the voltage  DECREASE as you go from 20:1 (least compression) to 4:1 (most compression, lowest volts).

Test 2
Also see this thread for a more precise test of output voltage after calibration:
http://groupdiy.com/index.php?topic=20058.msg708603#msg708603

Test 3
http://groupdiy.com/index.php?topic=20058.msg713493#msg713493

Good luck!

Again...  sooo close here! 

What seems to be working

• Compression is working as I can hear an audible difference
• Release is working as I can hear an audible difference

What I'm questioning

• Attack - The pot works as I can turn compression off or on, but question if the attack function is working as I cannot hear an audible difference.
  
• Ratio Buttons - I think I'm at a point where it's working correctly and hoping someone could confirm the following test results that Don recommended.  These three tests are all related to the ratio buttons.

Test 1  - Voltage Decrease
As as a reference point... I ran this test with my attack off and release fully CW.  I then ran my DAW's signal generator plugin into the 1176 at 1khz and measured 0.775 vac at the input and output. (I had to drop the signal generator to -11.4Dbfs to get 0.775).  I then turned the attack on fully cw and got the following results.  As you can see I'm definitely seeing a decrease in voltage as I toggle between the different ratio buttons.  I'm thinking that's good, right?

20 = 0.447
12 = 0.376
8 = 0.346
4 = 0.294


Test 2  - Output Voltage (http://groupdiy.com/index.php?topic=20058.msg708603#msg708603)
I then followed the steps outlined in this link, and received the following voltage readings at the output.  My results are lower than Don's test.  Does this represent any issues?

20 = 0.462
12 = 0.403
8 = 0.387
4 = 0.363


Test 3 - Pad Measurements (http://groupdiy.com/index.php?topic=20058.msg713493#msg713493)
Troubleshooting:
Feed a 1K 0dB signal into the compressor.  In/Out/Att/Rel all set half way. Confirm that you see 0.775 VAC between input pin 2 and 3.

AC voltage between pad 22 and ground for:
20:1 - 420
12:1 - 202
8:1 - 121
4:1 - 054

DC voltage between pad 21 and ground for:
20:1 - 06.19
12:1 - 3.335
8:1 -  2.270
4:1 -  1.374

DC voltage between pad 19 and ground for:
20:1 - 0.862
12:1 - 0.862
8:1 - 0.862
4:1 - 0.862

Thanks in advance!

k

 

[dbonin]

Test 2  - Output Voltage (http://groupdiy.com/index.php?topic=20058.msg708603#msg708603)
I then followed the steps outlined in this link, and received the following voltage readings at the output.  My results are lower than Don's test.  Does this represent any issues?

20 = 0.462
12 = 0.403
8 = 0.387
4 = 0.363

To get values "close" to mine you really need to repeat the steps as I have outlined them, paying close attention to step 5.
I think you are missing this step maybe?  At any rate, on step 5 make sure your OUTPUT (ac across pins 2/3) is  measuring around 2.44 vac with the attack clicked OFF to begin with.. (note the other settings I outlined as well).
This  test simply verifies that you are getting the 10db drop at the output when in 20:1 ratio setting when GR is switched on. 
A 10 db drop from 2.44 vac will give you a reading somewhere NEAR .788 vac when in the 20:1 ratio position.
Once you are seeing that your other ratio readings should be close to mine as well.
I hope this make sense! 

You are VERY close... 

1.) Apply a 1 KHz, 0dBu signal, confirmed with your DMM at pin 2 and 3 of the input XLR (0.775 VAC).
2.) Move your DMM to pin 2 and 3 of the output XLR.
3.) Set output control for 0dBu (0.775 VAC) at the output.        <----      (My input sits now at 24 and my ouput at the dot between 48 & 36)
4.) Set attack full CCW (off position) set release to 7 or full CW for fast release. Set the Meter to GR mode.
5.) Set input control for +10dBu (2.44 VAC) at your output XLR.        <---------------- NOTE THAT NOW THE ATTACK IS OFF!! (My input sits now at the dot between 24 & 18, and my ouput knob sits between 48 & 36) (Measuring 2.44VAC on my DMM on the output xlr, pins 2/3)

6.) Turn the attack control ON (full CW) and observer the voltage drop at each of the ratio settings

For each of the ratios, on a rev D, you should be seeing something close to this, shown with attack on:
Ratio:
20 (Att On .788VAC)
12 (Att On .679VAC
8 (Att On .642VAC)
4 (Att on .585VAC)

 

[core64]

Test 2  - Output Voltage (http://groupdiy.com/index.php?topic=20058.msg708603#msg708603)
I then followed the steps outlined in this link, and received the following voltage readings at the output.  My results are lower than Don's test.  Does this represent any issues?

20 = 0.462
12 = 0.403
8 = 0.387
4 = 0.363

You are VERY close... 

1.) Apply a 1 KHz, 0dBu signal, confirmed with your DMM at pin 2 and 3 of the input XLR (0.775 VAC).
2.) Move your DMM to pin 2 and 3 of the output XLR.
3.) Set output control for 0dBu (0.775 VAC) at the output.        <----      (My input sits now at 24 and my ouput at the dot between 48 & 36)
4.) Set attack full CCW (off position) set release to 7 or full CW for fast release. Set the Meter to GR mode.
5.) Set input control for +10dBu (2.44 VAC) at your output XLR.        <---------------- NOTE THAT NOW THE ATTACK IS OFF!! (My input sits now at the dot between 24 & 18, and my ouput knob sits between 48 & 36) (Measuring 2.44VAC on my DMM on the output xlr, pins 2/3)

6.) Turn the attack control ON (full CW) and observer the voltage drop at each of the ratio settings

For each of the ratios, on a rev D, you should be seeing something close to this, shown with attack on:
Ratio:
20 (Att On .788VAC)
12 (Att On .679VAC
8 (Att On .642VAC)
4 (Att on .585VAC)

Thanks very much for your reply Don!  I see what I was doing wrong...  I was following the steps correctly, but had my attack off during the first initial steps when it should have been on.  I realized in your explanation that you were basically mimicking the -10dB Hairball calibration  step.  This is when I realized I needed to set my initial DMM reading with attack fully on etc for the first few initial steps before turning it off in step 5 and then back on in step 6.

Running the steps correctly as stated above, I received the following results...

20 (Att On .785VAC)
12 (Att On .671VAC
8 (Att On .629VAC)
4 (Att On .561VAC) 

Is it safe to say this proves the ratio buttons are working as they should?

Thanks again!

k

 

[dbonin]

Running the steps correctly as stated above, I received the following results...

20 (Att On .785VAC)
12 (Att On .671VAC
8 (Att On .629VAC)
4 (Att On .561VAC) 

Is it safe to say this proves the ratio buttons are working as they should?

Thanks again!

k

Perfect!!  Yes,  you are bang on. 

 

[core64]

Running the steps correctly as stated above, I received the following results...

20 (Att On .785VAC)
12 (Att On .671VAC
8 (Att On .629VAC)
4 (Att On .561VAC) 

Is it safe to say this proves the ratio buttons are working as they should?

Thanks again!

k

Perfect!!  Yes,  you are bang on. 

Nice!  Thank you very much Don!!

Ok, so last issue/question before I can call this build a complete success...

Attack -
The pot works as I can turn compression off or on, but question if the attack function is working properly as I cannot hear an audible difference in the transients.  I also don't see the meter reflecting the changes as I move the attack knob from slow to fast (CCW to CW).  I know the audible difference is slight compared to the release, but thinking I should be hearing/seeing something.

Questions...
1)  Do others hear a difference when using the attack?  The only thing I have to compare it too is the UA 1176 plugin, in which I do hear a slight difference in the transients when turning the attack knob.

2)  Is there a test I can do with my DMM to prove/disprove that my attack is working correctly, i.e. measure  drops/increase in voltage?  I do see a small change in voltage, but would be curious if there's a guideline that I compare my results to?

Ok, now I'm really, really close... :- )

Thanks!

Kenny

 

[andydiy]

The life want to sell Hairball 1176, after completion because I 1176DIY, I do not know how to adjust found QC, to know how to adjust it to come up with a friend to buy, the price of $ 453, the price does not include shipping.

Here are Photo and MOV

https://www.youtube.com/watch?v=Su7XBMKs_M0&list=UUsWLIJ1jcuSTZovayK9p8-A

 

[core64]

Attack & Release Validation Test

Is there a test that I can perform using my DMM on my Attack & Release pots to ensure they're working correctly?

Attack -
The pot works as I can turn compression off or on, but question if the attack function is working properly as I cannot hear an audible difference in the transients.  I also don't see the meter reflecting the changes much as I move the attack knob from slow to fast (CCW to CW).  I know the audible difference is slight compared to the release, but thinking I should be hearing/seeing something.

Release -
I'm highly confident that my release is working correctly, as I do hear an audible difference as you would expect.  Being somewhat anal retentive, I'd still like to prove it by performing a test using my DMM and comparing my results to a known working 1176.

Thanks,

k

 

[dbonin]

I posted this awhile back but I had a hard time finding it again so I'm posting it again to help out anyone who might want to check the placement of a few resistors that are EASY to swap...  take a look:
REV D Resistors that are easy to misplace if you are NOT checking resistor values ... you really must check each one just as you stuff them into the board for best results....
These are easy to swap even if you are checking!  Thought this might help someone...
  10k vs 10M
        R10  pre      10k
        R31  sla      10k
        R35  GRCamp      10k
        R45  On Ratio Board      10M
        R66  grmd      10k

  150k vs 150R
        R30  sla  150k
        R58  R58 on Ratio Board  150R
        R85  pre  150R

  1M vs 1k
        R13  pre  1M
        R36  GRCamp  1M
        R8  pre  1k
        R81  PS  1k
        R82  PS  1k

  270R vs 270k
        R4  pre  270R
        R41  GRCamp  270R
        R57    270k

  3.9k vs 3.9M
        R60  GRCamp  3.9k
        R65  grmd  3.9M
        R67  grmd  3.9k

  470k vs 470R
        R37  GRCamp  470k
        R54  R54 Located on Attack Pot  470R
        R61  R61 on Ratio Board  470R
 
  560k vs 560R 
        R33  sla  560R
        R62  ratio  560R
        R9  pre  560k

** grmd = gain reduction meter driver section
** pre = preamp section
** sla = signal line amp section
** GRCamp - GR Control amp section
** PS= power supply
** ratio = ratio board

 

[Alexwfm]

Hello!

I guess my problem has an easy fix but i just can't figure out.
The compressor works and sounds ok but I can't get the meter to get less than 3 db out of the zero while in gain reduction.

So in step 3 of the calibration, when I'm set up and measuring -10db attenuation at the output when toggleing the GR on and off, I cannot adjust R44 cause the meter doesn't get further down than 5 db from the zero.

I used a different VU meter and had to change R72 to be able to get to 0 while calibrating the Null trimmer.
Is there a resistor value I could try to change to obtain more "drop" from the needle?

Thanks in advance,
Cheers.
Alex