[BUILD] 1176LN Rev D DIY

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Correct.

Mike

narapo said:
Hi,

I am finishing the wiring of the 1176 Rev D and I need a confirmation :

- When using a DPST GR bypass on the attack pot, you don't need to connect the BLK, GRN and 22 pads on the Meter PCB
- You connect :
                       - main PCB 22 pad to the common lug of the DPST
                       - Ratio BLK to the OFF lug of the DPST, the main PCB ground and to the chassi ground
                       - Ratio GRN to the ON lug of the DPST

am I right ?
 
Hi,

i have almost finished my 1176 clone and start to check the attack and release function. When I send a Drum-Loop into the compressor, there is a noticeable change on the meter and can almost hear it, when I change the release setting. But I hear no audible change with the attack pot. Is that normal?

Hope somebody can clear that...

Thank!
 
Attack goes from fast to ultra fast so the difference is not that big but the range of the release is very wide. You should be able to hear a lot of difference. Especially on heavy compression settings.

 
The controls on the 1176 are confusing to some. The input level determines the compression level. More in more smoosh. Try it on a snare hit only. Turn the input to you see about 10 db compression. With the release at about 3. If you turn the attack up fast it should smoosh the crack out of the snare. If you turn the attack to slow (lower setting) The crack should come back. Remember a good compressor can do some light duty without it being obvious. But the attack should make a major difference at higher compression levels.

John
 
I'm planning on ordering a pair of rev d kits from Hairball. Can someone please confirm that for stereo linking of two units that all I need to buy is two 1176 Rev D kits with rev d PCBs and one stereo link kit.

I tried searching through this thread but it's hard with my terribly slow internet connection.

Thanks!
 
Hey guys.

I'm finishing up another Rev D. I have one done and working perfectly, it's partner isn't doing as hot. It's passing signal and the GR and VU meter are working fine but I'm not getting any compression. I've calibrated the Q-bias and Null adjust with no problem but I can't get the darn thing to compress.

I've un-wired everything and re-wired them back up.
I've resoldered most of the main board and ratio board.
I've checked for shorts on between pad 22 and ground which I figured would do this.
I've checked for other obvious shorts.
I've verified all the transistors.

I have no hum or buzz, just audio not being compressed. The weird thing is that when I switch ratios I get the normal meter moving around then getting back to zero.

This isn't my first 1176 but I've done everything I can think to do, anyone have some more ideas for where to look?
 
I had a similar issue on TWO Rev A 1.2.5's I just completed last week.  Mine ended up being op error - I installed a 270K at R41 - should have been 270R (my cheap DMM's stupid auto-ranging ballistics threw me for a loop on R41  :( )  A few things to check from my limited experience:

Do you have Audio at PAD22 with GR enabled?

Is that audio making it to C20/CR3 and C19/CR2 junctions?

If not, the sidechain audio has an issue somewhere and isn't making it into the GR Control Amp for full-wave rectification.  Confirm your connection to the Ratio Board's PAD15 is connected to the output pot's PAD15 - and confirm Audio is present there.

If you touch PAD7/Ground on the PCB do you get static/consistent gain reduction in proportion to you touching those pads?  Try this with the Release pot around 12:00.

What DC Voltages do you measure from PAD7 to Ground at all 4 ratios?  You should have varying -DC there depending on Ratio selection and rectified sidechain audio (just measure for -DC w/o any input and see what you get across all 4 ratios).

It sounds like Q1 and Q11 are working if you were able to complete Calibration Steps 1&2 (same boat I was in!).  My GR meter also jumped around when changing ratios - but I just couldn't get any GR until I realized R41 was incorrect due to my error (that was all it took to break the GR circuit!).



I'm no expert - so maybe someone more knowledgeable will give their expert diagnosis  ;)  I'll stay tuned...


Good luck!  8)
 
man, your a saint.

I didn't have to get past your first paragraph. I had done the same exact thing, there were 2 more 270k's in my 270R bag.

Working great now.

Thanks for the quick help
 
benlindell said:
I didn't have to get past your first paragraph. I had done the same exact thing, there were 2 more 270k's in my 270R bag.

Well no kidding!  That is just too crazy of a coincidence  :eek:

Since our issues have been similar up to this point - make sure you didn't put the 270R's on the Release Pots (should be 270K).  That's what I initially did!

I don't know if maybe Mouser did some funky packaging with the 270R/270K (would explain why I was so easily fooled by my meter's auto-ranging), or if this is just a seriously just a strange coincidence  ???  Did you order your Mouser Cart with the Hairball Cart Link?

benlindell said:
Thanks for the quick help

My pleasure - I have a lot of "giving back" to do around here  8)
 
 Be VERY VERY careful selecting components!!!! Most DMM's will auto range but you can on most select the range with the select button. Or what ever your meter has. And if "auto range always" pay regard to the actual reading.  

998 ohm is 1k. ETC! Know your meter. And get a cheap Cap meter too. Such as Kato suggested to me long ago. Gives me piece of mind. And will virtually eliminate troubleshooting the board.

Wiring problems... Different story...

NEVER even put a resistor in without checking it first. And double checking what you are looking at. Then solder it. Saves major headaches. It can be done while having a pint of beer also. Just takes longer.
LOL! And slower is better on this stuff.

Be careful and best of luck. :)

John
 
sorry, can you tell what are the blue capacitors in rev D?
Why so big?
thanks
 

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I finally managed to finish my rev d :)

After powering it up the first time I immediately blew R32 because of Skylars old wiring guide :(

I replaced R32 today and sound is passing thru, but I can't hear any compression or see any GR on the VU meter.
I tried to calibrate Q-bias, but nothing is moving when turning the trim pot.
Attack and Release pots have no influence on the sound.
Ratio Buttons have no influence either.
GR Meter shows far left (R44 normal) or 0db when in calibration mode (R44 jumper moved)
It seems that the Output is very loud ! I had to turn my adam a7 to -60db so I could see something in the meter and not turn deaf.

If I understood the schematics right, something in my GR CONTROL AMP section isn't correct.
I double-checked if the Attack DPST Switch ist wired correctly and if there is no link between Pad 22 and ground.

How can I easily track down the problem I have ? Which points can I mesure with my DMM so you can help me ?
 
ilfungo said:
thanks Canidoit
but what position would be in the REV D?
thanks
On  my 1176 rev D journey thread. Theres a BOM list in there that marks which components are used for Signal Pre-amp path and Signal Line Amp path. I marked them so that if I or people want to pimp up the components like the caps and resistors in those path, they know which to do so. A poster told me that these are the components people use Orange drops and carbon comps for and from what I recall the Atoms were used in the power or filter section?... I think. It's been a while since I did the Rev D and asked people heaps of questions on it and only on the old 1176 have I seen people use Atoms.

There was a thread either here or at Gearslutz where a person asked why one of the 1176 units had Atom caps, if I find it, Il send you the link.  :(
 
kosty said:
I finally managed to finish my rev d :)

After powering it up the first time I immediately blew R32 because of Skylars old wiring guide :(

I replaced R32 today and sound is passing thru, but I can't hear any compression or see any GR on the VU meter.
I tried to calibrate Q-bias, but nothing is moving when turning the trim pot.
Attack and Release pots have no influence on the sound.
Ratio Buttons have no influence either.
GR Meter shows far left (R44 normal) or 0db when in calibration mode (R44 jumper moved)
It seems that the Output is very loud ! I had to turn my adam a7 to -60db so I could see something in the meter and not turn deaf.

If I understood the schematics right, something in my GR CONTROL AMP section isn't correct.
I double-checked if the Attack DPST Switch ist wired correctly and if there is no link between Pad 22 and ground.

How can I easily track down the problem I have ? Which points can I mesure with my DMM so you can help me ?

I'll see if I have some time to do a cleanup drawing for the various versions of D and A pcb's a wiring diagram and help us all with the various parts. There is 3 styles of attenuators, 2 input or output transformers and a good deal of wiring to mess up. Add the switchboards this is a fairly complicated project.

From memory your attack switch should have one wire from the PCB to the center pin (Common). Another wire should go from the ground to the Off (N/O)position terminal and then carry over to the ratio PCB/switch. Last another wire should go from the ON (N/C)terminal to the ratio pcb/switch. There is no need for any green or black wires on the metering switch set, when using the switched attack pot.

So if you turn the attack knob all the way CCW counter clockwise, the switch toggles on and the (common and N/O) should be connected. When you have the Gain reduction turned on so CW, with the switch now off you should have the (common and N/C) connection connected and now showing continuity or Ohms during the varying part of the pot.

Hopefully that makes sense... been up most of the night.
 

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