Re: MS76
« Reply #20 on: July 11, 2015, 03:05:20 AM »
Errata

Correct bridge to doubler.
Invert phase on blend output.
Reverse bypass switch

Ill post the corrected schematic when I have double checked everything.

Gustav


Re: MS76
« Reply #21 on: July 14, 2015, 01:28:50 PM »
Finished and calibrated the rev1 today.

Full list of errata for rev 2.

- Correct holes for meter mounting.
- Shorten Att/rel mount PCB
- Correct error in PSU
- ALL marked on/off/on, should be on/on.
- In/Output pot bank reversed for reverse mounting
- Blend circuit inverted.

Will rip up and reroute the main board properly.

rev 2 boards will start manufacturing July 27th. Shouldn't be more than a week or two underway after that.

Let me know if theres any interest for the first run..

Gustav

Re: Build Thread:MS76
« Reply #22 on: August 01, 2015, 08:02:25 AM »
Rev 2 boards will be ready Tuesday.

Gustav

gaetan

Re: Build Thread:MS76
« Reply #23 on: August 21, 2015, 08:22:01 AM »
Gustav, this thing is genius!

Blend in M/S mode gives so many option, overall it sounds beautiful, i'll try to post sound examples soon.

I have to say, the calibration was a bit of a nightmare but it is worth doing it, i would suggest anyone doing the build to use precision trimmers for Qbias, Zero and Trk.



Re: Build Thread:MS76
« Reply #24 on: August 21, 2015, 02:06:51 PM »
Gustav, this thing is genius!

Blend in M/S mode gives so many option, overall it sounds beautiful, i'll try to post sound examples soon.

I have to say, the calibration was a bit of a nightmare but it is worth doing it, i would suggest anyone doing the build to use precision trimmers for Qbias, Zero and Trk.

Thanks :)

Calibration is 100% identical to the standard 1176 calibration. Ill write it up when I have an assembly guide ready.

Just remember to switch off MS and "all" before doing it, and you can follow any calibration procedure for the 1176.

Gustav

miszt

Re: Build Thread:MS76
« Reply #25 on: November 27, 2015, 01:36:49 PM »
love the idea of this, i do allot of M/S compression in software, think this will be my next project!

what comes with the component kit? is it everything except the rack/front panel and power transformer? or are there other things I'd need to get? (apart from nuts/bolts/wires)

Re: Build Thread:MS76
« Reply #26 on: November 27, 2015, 02:01:59 PM »
love the idea of this, i do allot of M/S compression in software, think this will be my next project!

what comes with the component kit? is it everything except the rack/front panel and power transformer? or are there other things I'd need to get? (apart from nuts/bolts/wires)

Thanks :)

The content of the kit is explained on the site pcbgrinder.com in the components kit section.

Gustav

miszt

Re: Build Thread:MS76
« Reply #27 on: November 29, 2015, 06:27:16 AM »
thanks for the reply Gustav!

I did read it through, I was bit a confused tho, as you put "mounting hardware" and "mounting, hardware" on different kits, wasn't sure which was the typo and what you specifically meant? I think it means everything but the panel/rack/power trafo, but i don't want to assume, i'd rather order everything from one place in one go...

Re: Build Thread:MS76
« Reply #28 on: November 29, 2015, 07:10:26 AM »
thanks for the reply Gustav!

I did read it through, I was bit a confused tho, as you put "mounting hardware" and "mounting, hardware" on different kits, wasn't sure which was the typo and what you specifically meant? I think it means everything but the panel/rack/power trafo, but i don't want to assume, i'd rather order everything from one place in one go...

"What's not in the components kit?

A case & mounting hardware (Info in the Cases & panels section with a full list of suggested mounting hardware)"


I give a very specific reference for a very specific list for a very specific design for each project, but of course, it will vary with the way you design your case and panel, and with the project in question.

It may be more abstract than I realise, but it seems to make sense for most people...

Gustav

miszt

Re: Build Thread:MS76
« Reply #29 on: November 29, 2015, 02:17:09 PM »
maybe its just me, but because the GSSL description says "mounting, hardware", I couldn't be certain... but ok i guess my first assumption was right!

what does the transformer option involve? do I just need to get the transformers, or other components aswell?


Re: Build Thread:MS76
« Reply #30 on: November 29, 2015, 02:24:14 PM »
maybe its just me, but because the GSSL description says "mounting, hardware", I couldn't be certain... but ok i guess my first assumption was right!

what does the transformer option involve? do I just need to get the transformers, or other components aswell?

Hi Miszt.

Would you mind sending me a mail with any questions you may have about the kits? I think this thread would be better off reserved for build issues rather than a direct conversation between the two of us, answering questions directed at me specifically :)

As a response to your last question here - just the transformers.

If you really want to go deep into the shopping list and make sure you cross every t and dot every i, get the schematic on the site and work through it...that should do it!

Hope that helps!

Gustav
« Last Edit: November 29, 2015, 02:31:10 PM by Gustav »

Re: Build Thread:MS76
« Reply #31 on: December 17, 2015, 03:03:32 PM »
Hi there, could anyone tell me the requirements/specs for the vu meters.

Cheers

Re: Build Thread:MS76
« Reply #32 on: December 18, 2015, 02:25:53 PM »
Never mind on the meters, I caved and bought the ones from pcbgrinder. :)

What pots do you use for this build, I noticed that the panel holes are 10mm diam. cut out, which is much larger than a standard Alpha pot?



Re: Build Thread:MS76
« Reply #33 on: December 19, 2015, 01:06:36 AM »
Never mind on the meters, I caved and bought the ones from pcbgrinder. :)

What pots do you use for this build, I noticed that the panel holes are 10mm diam. cut out, which is much larger than a standard Alpha pot?


Hi Rimmett.

VU meters should just be VU meters. Ballistics are usually better on the more expensive meters, but any VU should do.

If you are doing your own shopping - For pots, it is way easier to find a pot and adjust the hole on the panel layout, than stick with the (somewhat random) hole size and chase a pot.

Gustav

Re: Build Thread:MS76
« Reply #34 on: January 04, 2016, 09:39:30 AM »
Can anyone advise are the resistors 1/4w or 1/2w

Re: Build Thread:MS76
« Reply #35 on: January 06, 2016, 09:29:18 AM »
Can anyone advise are the resistors 1/4w or 1/2w

bump, looking to get going on this, anyone....

I ask because the silkscreen seems large for 1/4w

Re: Build Thread:MS76
« Reply #36 on: January 07, 2016, 03:53:40 AM »
Can anyone advise are the resistors 1/4w or 1/2w

bump, looking to get going on this, anyone....

I ask because the silkscreen seems large for 1/4w

1/4 watt is fine.  Not sure why you'd think the silk screen seems large for that. For reference, its whats used in the assembly guide.

Gustav

Re: Build Thread:MS76
« Reply #37 on: January 07, 2016, 08:34:44 PM »
Thanks Gustav, I build a lot of euorack modular stuff and I guess due to form factor restrictions the footprints seem smaller (just what I'm used to). I'm glad to hear that I can just pick parts out of my inventory  ;D

hugo

Re: Build Thread:MS76
« Reply #38 on: February 27, 2016, 06:10:18 AM »
Hi All,
My name is Hugo, i'm from France and it is my first post on this forum, even if it helped me a lot on the past ; thanks all for your contributions.

I just finished my MS76 and not any problem, it works well....but i have some general questions about troubleshooting some details...i think gustav has a lot of questions to answer so if anybody can answers, it would be great.

- Left and right are not really matched, which transistors can i change to have the same gain and compression on both channels ? during the calibration, it seems that the input of right channel is lower than the left one. I can measure HFE but not sure about which transistors to change for a complete matching of gain and compression.
- The blend is working well, but it affects the L/R balance..i saw some posts about it, is there one solution ?.
- When i switch to dual mono, i really don't have the same sound than in stereo mode, is it normal ?
- In the stereo mode, with both vu meter on "GR", the left moves good whereas the right one do not move, or just a little bit, is it normal, or may i have the same gain reduction tracking on both channels  (the signal sent to the left is the same as the signal sent to the right) ?

Re: Build Thread:MS76
« Reply #39 on: February 27, 2016, 06:13:22 AM »
Hi All,
My name is Hugo, i'm from France and it is my first post on this forum, even if it helped me a lot on the past ; thanks all for your contributions.

I just finished my MS76 and not any problem, it works well....but i have some general questions about troubleshooting some details...i think gustav has a lot of questions to answer so if anybody can answers, it would be great.

- Left and right are not really matched, which transistors can i change to have the same gain and compression on both channels ? during the calibration, it seems that the input of right channel is lower than the left one. I can measure HFE but not sure about which transistors to change for a complete matching of gain and compression.
- The blend is working well, but it affects the L/R balance..i saw some posts about it, is there one solution ?.
- When i switch to dual mono, i really don't have the same sound than in stereo mode, is it normal ?
- In the stereo mode, with both vu meter on "GR", the left moves good whereas the right one do not move, or just a little bit, is it normal, or may i have the same gain reduction tracking on both channels  (the signal sent to the left is the same as the signal sent to the right) ?

I replied to your mail, but will reply here as well.

I think most of the problems can be boiled down to the misunderstanding that the unit has a stereo mode. You can either use is in dual mono or M/S. In M/S mode, you can do stereo track processing, but one channel will be referenced to the M content, while the other will be linked to the S content.

I hope that clears up some issues.

Edit:And as mentioned in the calibration guide, its important that the unit is not in M/S link mode while you calibrate.

Gustav