Stereo 1176 support - Mnats/Hairball

[DaveHilltop]

germoju,
  No I didn't add the stereo link boards. I have the boards and components but I don't see myself using it in stereo mode much. I'll probably add them down the road when I'm feeling the need to DIY Right now just enjoy it as is. Same for the bypass capabilities. I have a Drawmer 68ME that I use as a stereo buss compressor so I really intend to use the 1176 for recording and mixing individual tracks. Thanks for the compliment on the pics. I'm very happy how everything turned out   Regards, Dave

 

[100WChris]

Hi!
Finally finished my Stereo-1176  ;D

looks wild, but the unit is totally quiet

transformer and link-boards are under the main-pcbs

 

[mrerdat]

Nice!  I love how much space you gain by tucking the transformers and stereo link boards under the main PCBs.  I didn't even notice the little mounting bracket for the output transformer at first glance.  Very cool. 

 

[mnats]

Hi!
Finally finished my Stereo-1176  ;D

Looks great!

Why not post it to the official Hairball Audio: 1176 Stereo Linking PCBs Support Thread as well, since it looks like you used Hairball's boards?

 

[100WChris]

done
EDIT: mrerdats layout from post 66 helps a lot!!

 

[DaveHilltop]

100WChris,
  Sweet looking build !! Congrats   Regards, Dave

 

[mnats]

done

Great, thanks!

EDIT: mrerdats layout from post 66 helps a lot!!

Unfortunately the grounding scheme for the XLRs on that drawing isn't ideal. But we'll save the best advice for the official thread

 

[EvLoutonian]

Hi guys.
I have a pair of old UTC H-8 input / matching transformers.
I 'm wondering if they would be suitable for my stereo 1176 input transformers.
They are military spec transformers, and freq response is indicated as flat from 50-10k Hz, but the spec sheet also suggests that they are good for beyond that range.

Cheers,
Evan.

 

[mrerdat]

Unfortunately the grounding scheme for the XLRs on that drawing isn't ideal. But we'll save the best advice for the official thread

I agree with you there... it was a pretty hacky workaround for when I had floating PCBs in my case secured with gaff tape since I didn't have the tools/time to properly drill and mount things to the chassis before a big project that I had a few months ago.  I'll edit that post with a warning so I don't mislead people with bad grounding.

Probably the most helpful thing from my drawing is how the stereo link boards are connected.  I found the info a bit scattered and confusing while working on my build so it's nice to see that in one place.

 

[100WChris]

Probably the most helpful thing from my drawing is how the stereo link boards are connected.  I found the info a bit scattered and confusing while working on my build so it's nice to see that in one place.

That´s exactly what i used it for 
Thanks for your effort!
Chris

 

[dmnieto]

Hi everybody!

Some miscellaneous questions about my 1176 build, basically parts:
1. switch, should i use:[/li type=decimal]Meter

• http://www.mouser.com/ProductDetail/Lorlin/CK1592/?qs=sGAEpiMZZMtdU8v%2fCHkq3yHDk2fm8aQh
• http://www.mouser.com/ProductDetail/ALPS/SRRM433700/?qs=4QwOlnKYOEsVs7%252b5af2rdg%3d%3d
• if I want to have the +8 as well? http://www.mouser.com/ProductDetail/ALPS/SRRM342800/?qs=4QwOlnKYOEtMus9aF%252bYBQQ%3d%3d

2. power led and holder...  any recommendations?
3. knobs: I would really like to find something similar to the 2-1176 from UA, I kind of like those roundy knobs. Alternativelly I wouldn't mind to get some metallic/aluminium ones, of white or gray color and cylindrical. Any recommendations? 

 

[Unit7]

Hi everybody!

Some miscellaneous questions about my 1176 build, basically parts:
1. switch, should i use:[/li type=decimal]Meter

• http://www.mouser.com/ProductDetail/Lorlin/CK1592/?qs=sGAEpiMZZMtdU8v%2fCHkq3yHDk2fm8aQh
• http://www.mouser.com/ProductDetail/ALPS/SRRM433700/?qs=4QwOlnKYOEsVs7%252b5af2rdg%3d%3d
• if I want to have the +8 as well? http://www.mouser.com/ProductDetail/ALPS/SRRM342800/?qs=4QwOlnKYOEtMus9aF%252bYBQQ%3d%3d

2. power led and holder...  any recommendations?
3. knobs: I would really like to find something similar to the 2-1176 from UA, I kind of like those roundy knobs. Alternativelly I wouldn't mind to get some metallic/aluminium ones, of white or gray color and cylindrical. Any recommendations?

I'm planning to do a stereo unit too. Doing some research from time to time, and regarding the knobs I found these at eBay (only 1/4 shaft though):
http://www.ebay.com/itm/TWO-new-copy-3-4-RCA-type-knobs-black-w-white-line-standard-1-4-shaft-KA-/321203133973?pt=US_Vintage_Pro_Audio_Equipment&hash=item4ac932de15

 

[dandeurloo]

Hairball audio may have the knobs.  Check with Mike.

 

[dmnieto]

I'm planning to do a stereo unit too. Doing some research from time to time, and regarding the knobs I found these at eBay (only 1/4 shaft though):
http://www.ebay.com/itm/TWO-new-copy-3-4-RCA-type-knobs-black-w-white-line-standard-1-4-shaft-KA-/321203133973?pt=US_Vintage_Pro_Audio_Equipment&hash=item4ac932de15

Wow, $24 for TWO? That is crazy, are they made of emeralds?

 

[dacapitan]

I have a similar question to the ones asked previously...

Are these the correct Rotary Switches for the Meter and Ratio Board - I found them in a Rev D BOM

(4 Pole - 3 Positions)
http://uk.mouser.com/ProductDetail/Lorlin/CK1057/?qs=%2fha2pyFaduj4gRj15JfhdorbufEvFJfJXuu%252bEv8koNc%3d

(2 Pole - 6 Positions)
http://uk.mouser.com/ProductDetail/Lorlin/CK1055/?qs=%2fha2pyFaduhJ%252bdXyu7eNQ9qHO86SsLfFT1B9cn15eVo%3d

Which is ambigious to this found on Mnats Page

2 Pole - 5 Positions)
http://uk.mouser.com/ProductDetail/Alpha-Taiwan/SR2921F-0205-19R0B-E9-S-W/?qs=sGAEpiMZZMvNbjZ2WlReYnqYHrQfuERs6ym%252bj4ABW1I%3d

I noticed DIYRacked Case to have 2 labeled Positions for the meter switch and 6 for the Ratio and Collective cases has 3 positions for the Meter Switch and 5 positions for the Ratio?

Also, is there a measurement for the gaping Power Switch hole on either case?

A Bit Confusing with no definitive answers floating around - Please help!

 

[dmnieto]

On the collectivecases one the GR bypass is in the meter, so you need 3 positions in the meter switch and 5 positions (4,8,12,20,ALL) in the ratio one.

On the other case the GR bypass is actually in the ratio board (marked as position 1) so you are going to need a 3 pole 6 positions for the ratio and a 2 pole 2 positions for the meter

 

[dmnieto]

Also... those references from lorlin... isn't the shaft way too long? 38mm feels a bit too much.

What is the recommended shaft length for the collectivecases case?

 

[dacapitan]

On the collectivecases one the GR bypass is in the meter, so you need 3 positions in the meter switch and 5 positions (4,8,12,20,ALL) in the ratio one.

On the other case the GR bypass is actually in the ratio board (marked as position 1) so you are going to need a 3 pole 6 positions for the ratio and a 2 pole 2 positions for the meter

Okay I understand the visual differences on the Face Plate of the Two and how they would require different position amounts and where the change in positions between the two is due to bypass being on the ratio or meter switch - but is that not determined by the PCB / wiring rather? you say 3 Pole 6 positions but the board only fits 2 pole and 4 pole? - Is there a different way of wiring for different position amounts?

(4-pole - 2 pos (Meter) / 2pole- 6 pos. (Ratio) - [DIY Racked labeling])

(4 pol - 3 pos. (Meter) / 2pole - 5 pos (Ratio) - [Collective Cases labeling])

The latest and previous BOM on mnats page only calls for a 2 and 4 Pole Lorlin rotary switch - no positions mentioned

The original rev D BOM calls for a 4 Pole 3 Position / 2 Pole 6 Position - defined but ambiguous to the case labels.

This makes it really hard to know which Switches to Choose - Could someone please provide an explanation?

With Regards to Lorlin shaft lengths, they are long and plastic and need to be trimmed to your required length.

 

[dmnieto]

Sorry, I meant two pole / 6 positions

I honestly dont know how to wire the 1:1 ratio in the diy racked case...

 

[dmnieto]

I am doing some modifications to my stereo 1176...

1. I am adding the super-slow attack mode by using the SPDT switch in the attack pot to either have a 0.022uF (max 0.8ms time) or a 0.22uF (~8ms attack time)
2. I am cannibalizing some of the MC77 design to build a small side board that does the following:
  a) In/Out real bypass (with buffered meter option)
  b) relay switched 150Hz HPF sidechain
  c) relay switched send/return sidechain
  d) relay switched stereo link (because i cannot fit in my case DPDT switches with the DPDT power switch).
  e) Dedicated 24V power supply for switches and lamp.

The board is going to use SMD resistors to save space, I will try to get the schematics sanitized first here, but after that I can share the pcb files if somebody is interested.