Build Thread:MSHOL

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Gustav

Well-known member
Joined
Jun 4, 2004
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Location
DK
MSHOL.

Hand of Light/LA series inspired opto compressor in two channel format.

I included the link, which is, to put it nicely, unreliable for real stereo tracking. It does gives a linkage of the channels, which is better than nothing, or at the very least a different effect than dual mono.

I also used the MS separation trick for faux stereo tracking (again, LR should be stable - and matching errors will cause (to me) less critical shifts in the m/s balance.

The mono channel is, in my opinion, the best sounding comp I have built and used, and I am really looking forward to seeing what this will add to it - or if it will even work!  ;D

rev 2 PCBs avaliable
Documents at the bottom

https://pcbgrinder.com/index.php?route=product/product&path=59&product_id=206

This is a new project, so there is no FAQ and maybe some possible issues I haven't even thought about, but Ill do my best to help out if you have any questions, or if some error I did not catch shows up. This is how these things usually work....

Gustav
 
Managed to fire this up today.

Its first reaction was showing me -1/+1 on the supply voltage (Separate PSU board showed +15/-15 unconnected.

Then proceeded to remove ICs, which made the relays and power rails come alive.  (excellent!)

Placed ICs one by one.

5532 manufactured smoke.

After a bit of checking the circuit, I double checked the supply pins, which are reversed.

Will do some hacking and try again.

Gustav
 
Reversed the supply pins on the 5532.

Everthing seems to be working. Will check the details next week and lay out a new board.

Gustav
 

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Full list of errata for rev. 2

PCB

- Reverse output pot for upside down PCB mounting (Add ”Mount to back” on pot control board)
- Correct MS/link/split switch mode
- 2 x 6,8uF elco back to back caps in series in the HOL project were replaced by two poly caps in MS HOL rev 1. Removed footprint for one in MS HOL rev 2 (two is a waste, since they were replaced by poly caps. Kept the value at 6,8uF though).
- Changed meter LED supply from parallel to series
- Reversed supply voltages for 5532

Front panel

- swapped MS/split
- Moved ”top controls" 3mm down, "bottom controls" 1mm down.
- Corrected meter hole mounting.
- Reversed VU/GR meter switching

That should do it....

Rev 2 PCB gerber is done and ready for manufacturing after the holidays. (Juli 27th). Rev 2 front panel is done in FPD format.

Gustav
 

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This looks very promising... could you do a little demo when finished?  What is the drive switch for?

thanks
weiss
 
weiss said:
This looks very promising... could you do a little demo when finished?  What is the drive switch for?

thanks
weiss

Not sure about demos.

The drive is just a boost.

Gustav

 
weiss said:
Gustav said:
Not sure about demos.

The drive is just a boost.

Gustav

no problem. Loudness boost?

If you are asking if its a flat boost or a loudness boost (a la hi-fi equipment loudness curve boosts), the answer is, its a flat boost.

If you are asking something else, let me know :)

Gustav
 
Gustav said:
If you are asking if its a flat boost or a loudness boost (a la hi-fi equipment loudness curve boosts), the answer is, its a flat boost.
If you are asking something else, let me know :)
Gustav
Sorry, i meant volume boost. Now i understand ;)
 
hello there, just received my pcb yesterday and started to populate it, but need some precision about the DPDT relay, I  have some in stock but none of those is compatible with the footprint on the pcb ?
Can someone give me a reference I can order ?

Also if you got any eu based supplier for the Vactrol ? I only know Banzai but any input is welcome :) .

thanks to Gustav the board is neat, looks like a really easy build clever component value etc ... , hope I would have not too much troubleshoting anyway :) .
 
p0ulp said:
hello there, just received my pcb yesterday and started to populate it, but need some precision about the DPDT relay, I  have some in stock but none of those is compatible with the footprint on the pcb ?
Can someone give me a reference I can order ?

Also if you got any eu based supplier for the Vactrol ? I only know Banzai but any input is welcome :) .

I think this should be good, but check the data sheet first.

http://www.banzaimusic.com/Omron-G5V-2-12VDC.html

Same place as where you can get the opto couplers :)

Gustav
 
another question, I m still missing the 6u8F capacitor, I did have some which are really big, Wima make a 6u8F for $$$, is there alternative for cheaper which fit the board ? I did find lots of tantalum alternative but I m not sure if it's ok,those cap seems to have audio through them before the 5532 are they here to filter something  ? 

What is the role of the 139/140 ?  Just curious I have only seen them as "amplifier" before and don't undertand why the signal have to be amplified before the That1240

At the end what kind of cap could I chose ? As always I try to build as clean as possible and keep component package the way they are designed.

I m sorry if this is really basic understanding but I also build those to learn  ;)
 
Hi there,

I'm having the component kit of the MS-HOL and the MSPQ76. Can you tell me what current of the trafo is advised? Like I can choose from an 2,66A and 1A output?
 
Sorry for missing this post.

p0ulp said:
another question, I m still missing the 6u8F capacitor, I did have some which are really big, Wima make a 6u8F for $$$, is there alternative for cheaper which fit the board ? I did find lots of tantalum alternative but I m not sure if it's ok,those cap seems to have audio through them before the 5532 are they here to filter something  ? 

Mainly used to block DC through the circuit - you can use lower values in some places, but would have to calculate that by yourself. I just grab the 6,8uF


p0ulp said:
What is the role of the 139/140 ?  Just curious I have only seen them as "amplifier" before and don't undertand why the signal have to be amplified before the That1240

HOL output stage, drives the trafo. 1240 does "butt in" when MS in engaged.  I do things by trial and error,  so it something thats honestly not optimal in theory, but works in practise.

Gustav
 
Kieftenbelt2 said:
Hi there,

I'm having the component kit of the MS-HOL and the MSPQ76. Can you tell me what current of the trafo is advised? Like I can choose from an 2,66A and 1A output?

If your spec is given for parallel connection of the secondaries, I would go with the 2.66, if its given for center tap/series connection, 1A is good.

Gustav
 
TCMusicProductions said:
quick question.

in the kit, there are 2 log pots and 2 lin. pots.
My guess is that the lin. pots are used for the output and the log pots for threshold control. is this correct?

Check the errata document  - this, and a few other details you dont want to miss, are covered there.

Gustav
 
Hi!

I built a stere HOL out of the old HOL boards but it should fit in that Topic...
I used OPA2604/604 instead of the three opamps in the audio path. My Problem is that I'm getting different Output Levels out of the two channels. One channel is a few db louder than the other and also sounds better (with adjusted Levels). I cannot really tell if the loss of level comes from the output stage or the compression (->threshold?).
Do you have any suggestions what that can be? The "better" sounding channel has more depth, a little more high end I think and sounds more open.
 

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