Hairball Audio: 1176 Stereo Linking PCBs Support Thread

[CapRock]

you do not need another board for bypass.  If you look at the wiring diagram you will need 1 SPDT switch per unit as well as one stereo link pcb per unit, or you could run both units to a single DPDT switch.

 

[Echo North]

For the bypass do i need something else.....ie another board or anything?

What do you mean by "bypass".  The 1176 doesn't have a true bypass, just a GR off.  The GR off is usually placed as a switch on the attack pot.

 

[Brotastic]

ok, cool.  I apologize if that was a newb question....but well I am a newb.    Someone told me that I needed a board to hook up the toggle up to for the comp/bypass for the stereo 1176.  Thank you guys for clarifying this for me. 

 

[Brotastic]

For the bypass do i need something else.....ie another board or anything?

What do you mean by "bypass".  The 1176 doesn't have a true bypass, just a GR off.  The GR off is usually placed as a switch on the attack pot.

so, on the front panel of the 2-1176 it has a place for a bypass.......is that not a true bypass?  I apologize for my ignorance. 

 

[CapRock]

I posted the following about a week ago can anyone lend some sugestions....

Hey guys.  Does anyone have a list of voltages I should be reading at tl071 and tl072?  I am getting proper 30vdc to the 30v pad.  My 2 rev D's work perfectly in mono but when I flip the switch to stereo I get no gain reduction.  The meters do not show any reduction and there is no "actual" gain reduction.  In stereo mode i still get sound from both units just no reduction.  I wired it up exactly as on the hairball diagram, with the exception of mounting my switch in an exernal enclosure.  I used a dpdt instead of 2 spdt's and connected a TRS cable from each mono comp to the external enclosure.  I jumped the 2 comps together with a TRS cable as proposed in the diagram. Other than the voltages if anyone has any ideas please chime in, thanks...

 

[speakerface]

For the bypass do i need something else.....ie another board or anything?

What do you mean by "bypass".  The 1176 doesn't have a true bypass, just a GR off.  The GR off is usually placed as a switch on the attack pot.

so, on the front panel of the 2-1176 it has a place for a bypass.......is that not a true bypass?  I apologize for my ignorance.

This reply would probably be more at home on a different thread, but the short answer is that the mnats boards kit does not have a true bypass.  However you do have some options for using that space depending on your needs.

If you're just looking for something to plug the hole so to speak, you could easily wire what is supposed to go the the SPDT switch on the attack pot (from both channels) to a DPDT on the front panel...you'd still get all the coloration of the input/output transformers with no gain reduction.  Turning it on and off wouldn't truly show how the unit is affecting your sound.

If you want true bypass and don't mind a back panel switch, you could easily add a DPDT to each channel (or a 4PDT for both channels) of the compressor sending the input signal to either the input pot or directly to the output.

If you want true bypass from a front panel switch, the only good way to go is some sort of a relay set up.  (You could also do the back panel method, but I assume too much noise would be induced on a run that long).  Igor makes some bypass PCBs available in a couple of different sizes (check white market section), but I don't believe either of them fit Dan's case perfectly (anybody feel free to correct me here).  These are set up for board mounted XLR connections and you'd need to wire power to the board in addition to the front panel switch.  If your XLR spacing isn't correct you could use these boards, but wire them to the XLRs instead of board mounting.   

I am currently building one as well and plan on doing a relay bypass on perfboard with a front panel switch (after I get the thing working without bypass) as well as having the attack pot SPDTs.

Hope that helps.     

 

[Brotastic]

Thanks for the reply.  It does help.  Yeah, I thought that maybe I could rig it to the stereo board, but I guess not.  Let us know how you do the bypass.  I would love to see it.  Thanks again. 

Dan

 

[a zombie]

Just finished mine and I'm not sure if it's working propery... :-\

Should the meters on both 1176s move even if only one is being fed audio?

When I engage the stereo link I get less GR, is that normal?

I have +30 on the +30 pin, around +15 on the in's and out's.

The ground connection on the SL board is directly connected to my star ground.  The link and loop wires are shielded, with the shield connected on the switch end to the audio ground.  The in/out's are connected to a TRS jack via a shielded cable, with the shield only connected to chassis ground on the TRS jack.

EDIT:  I attached a drawing of how I wired it, sorry about the crapiness of it.

 

[Echo North]

Well the way you have it linking would be engaged with the switch in the down position.

Do you have the onboard wire jumper installed?  it's net to the info text on the PCB.

 

[Echo North]

You should see summed audio coming out of the "link" pad.

 

[a zombie]

Well the way you have it linking would be engaged with the switch in the down position.

Do you have the onboard wire jumper installed?  it's net to the info text on the PCB.

It is wired to a push/pull output pot, so pulling it out engages the link.

You should see summed audio coming out of the "link" pad.

Turns out I forgot to install the jumper on the St. Link board.  Now it works REALLY GOOD.  tracking is damn near perfect with two hairball/mnats rev D's.  Probably due to the excellent FET matching that Mike does.


...so if you're in the process of stuffing the stereo link board

MAKE SURE YOU INSTALL THE JUMPER!!! IT IS EASY TO MISS!

 

[Autophase]

Hi guys I have decided to build a stereo 1176, well 2 actually one for me and one for a friend.
I obviously intend to use the stereo link kit and I will get matched pairs from hairball, but I have 2 questions.
1: can I easily make the stereo compressor use a single set of controls as opposed to having 2 sets of mono controls, or.would you suggest it's better to have them both available to help with adjustments for tracking differences?
2: which revision is best if I intend to stereo link? I see a lot of you using revision D. Does it make a difference?
Thanks

Sorry for self bump, can anyone answer my questions above, id appreciate any advice RE: Building stereo units, I'm intending to buy my boards and components soon.

Thanks

 

[mnats]

1: can I easily make the stereo compressor use a single set of controls as opposed to having 2 sets of mono controls, or.would you suggest it's better to have them both available to help with adjustments for tracking differences?

Can you easily find a dual T pad with a single shaft?

2: which revision is best if I intend to stereo link? I see a lot of you using revision D. Does it make a difference?

I can't answer that question based on any personal experience but there's nothing intrinsic about the revisions that would make one specific rev perform better in a stereo link configuration than another. What might make a difference is that the G uses only a single pot for the input control; finding a dual pot should be a lot easier than finding the dual T pad.

 

[germoju]

hi guys,

i'm linking my units with the stereo kit BUT ... (!!??!!) i got questions !

1-  for the sidechain, I have to use a mono jack ? or stereo jack ? or nevermind ?

2 - On the stereo card, the ground goes to ground of the jack, right ?

3 - the +30V test point goes to +30V on main PCB R87 ?

4 -the IN goes to one pin of the jack ? And OUT goes to the other, right?

Sorry , I read all documentation but I too novice !
Please can ou help me with that ?

 

[a zombie]

1- either 2 mono jacks or 1 stereo jack.  The two units need to connect in to out and out to in, so if you use single stereo jacks on each 1176 then they will need to be wired opposite to accomplish this.  If you use 2 mono jacks on each, then you will wire the 'in' to one jack and the 'out' to the other jack.  To interconnect the two 1176's you would connect them in to out, and out to in.

2- On the stereo card the 'ground' terminal goes to chassis ground. 

3- yep

4- Yep, all you are trying to accomplish is to connect the two st. link pcb's in to out, and out to in.  There are multiple ways to do this as stated above.  but if you've only got 2 1176s, single TRS jacks wired inversely is the easiest, cheapest, and most convenient.

Also, be sure and use shielded wire for all the audio paths.  Connect the shields on one end only to prevent a ground loop.  For instance: on the connection between the st.link board and the jack, you should connect the shield to the sleeve/chassis connection on the jack only.

hi guys,

i'm linking my units with the stereo kit BUT ... (!!??!!) i got questions !

1-  for the sidechain, I have to use a mono jack ? or stereo jack ? or nevermind ?

2 - On the stereo card, the ground goes to ground of the jack, right ?

3 - the +30V test point goes to +30V on main PCB R87 ?

4 -the IN goes to one pin of the jack ? And OUT goes to the other, right?

Sorry , I read all documentation but I too novice !
Please can ou help me with that ?

 

[germoju]

thanks for your help
tomorrow I will do a draw tomorrow

 

[emrr]

Can you easily find a dual T pad with a single shaft?

Yes, vintage Daven on ebay, but it's gonna cost you around $400. 

Or buy a Goldpoint, also really expensive. 

 

[germoju]

hi,

I did a draw !
i will use 2 mono jack, IN and OUT.
But I dont know where solder the wire on the female jack.
See my draw :

I read on the hairball documentation that I can use the +8 button to remplace the link switch...
Do you know how to do that ?

 

[mnats]

Can you easily find a dual T pad with a single shaft?

Yes, vintage Daven on ebay, but it's gonna cost you around $400. 

Or buy a Goldpoint, also really expensive.

At least the tracking will be good so that's one problem solved.

You building one too Doug?

 

[germoju]

hi guys...

i just have a question about this stereo link PCB...

i have to solder a piece of resistor between the 2 points near the "hairball" logo ?
When I look at the circuit i think : "Yes, do it ! it makes sense !"
but I would like a PRO confirmation Can you tell me please ?