[BUILD] 1176LN Rev D DIY

[usekgb]

Hey all question:
I'm stuffing the power supply right now, and my C23 is a 6.8uF 100 volt capacitor instead of 6.8uF 35v (On the B.O.M).  Should I order the exact part or does anyone know whether it would be okay to use a capacitor thats 65v (100-35...) over the Bill of Materials part.  Also my rectifiers were 1N4004 instead of 1N4003, but I scoured the forum and found out those are okay to use, however anyone confirming that would be great.

I appreciate the help I've looked for the answer before posting this but havent found anyone who has encountered the same capacitor issue I'm having.

Thanks!

As long as it fits on the PCB, you're fine.  Going with a higher voltage won't hurt at all.  If anything, it may extend the life of the cap in that position.  Also, those diodes will be fine.  Enjoy your comp!  I love mine.

Cheers,
Zach

 

[number2]

Can someone confirm that it's ok to use Ceramic disc 200pf capacitors for C3 & C6?  the BOM states Mica's...

did this ever get answered? I have the same question

 

[usekgb]

I don't see why ceramic wouldn't work.  Someone correct me if I'm wrong, but it looks like they are part of the feedback section of the signal pre-amp, feeding the gain reduction FET.  Shouldn't be a huge deal.

Cheers,
Zach

 

[mrcase]

Hey!

Am I the only one with this issue? Could it be a calibration mistake? I would really like to solve this!!!!

thanks
M

hey all!

I´m enjoying my Hairball 1176 for quite some time now. The only thing that bothers me or strikes me as not quite right is the input threshold. It feels like it starts compressing too soon, especially compared to a original unit. this is a pity because I can´t drive the circuit as hot without having too much compression. Any ideas or hints where to start looking at?

thanks as always
M

 

[dmp]

Can someone confirm that it's ok to use Ceramic disc 200pf capacitors for C3 & C6?  the BOM states Mica's...

I think the general consensus is that NPO/COG ceramics are good in most applications.

 

[number2]

I think these came with the hairball mouser cart: http://www.mouser.com/ProductDetail/Xicon/140-50P2-201K-RC/?qs=SY6bF4iPirSvcgGt8%252bAkww%3d%3d
that's what I have. I guess I'll try them

 

[mrfunk81]

Hi everybody, I've read all the post but I can't find a solution to my problem:

1176 mnats board rev d 2.2 purcheased a couple of weeks ago from australia mnats.

R32 burn in a couple of seconds if I switch on the 1176.

The output trafo is wired correctly VIOLET, GREY, BLK, WH/RED, WH/BLK, BROWN.
I've 2N3708 instead of 2N3708, I don't know why, they were in mouser cart..

The MAIN voltage 30V are ok but others not match the voltage in mnats page..

I've no idea how can solve this problem, please help me.
Marco

 

[Soundmugician]

Just finished calibrating this unit today, so far everything calibrates and sounds good, as far as the distortion adj, I was reading somewhere that it wont make that much of a difference, and can just be set in the middle. Is this true? How important is that adjustment. Also on the bom it says to use 2n3708's but the original schematic says 2n3707's, I know someone who has the 3707's will it have much of a difference if i use 3707's instead of 3708's ?

Also id like to add, this build was pretty fun to do, and id have to say if you follow the instructions with surgical precision ( and have some electrical knowledge ) you should have no problems. Thanks mnats and all the other people here who make this possible for people like us ( diy'ers ) to tinker and build they're own gear!

 

[Soundmugician]

bottom view of the plotting of the standoff's

 

[braeden]

That's a good looking unit... what was the reasoning behind using two power transformers?

 

[Soundmugician]

That's a good looking unit... what was the reasoning behind using two power transformers?

Thanks! I wasn't sure about current draw n such, I have seen other dual units that were using 1 xformer, but I figured for only 25 bucks more could just have 2 and not worry about it. Is it possible to use just use one and wire the a/c out to each main board in parallel? I also read where you could take the rectified dc from one board and pass that to the other, just seemed more straight forward with 2 xformers.

 

[braeden]

Yes that's correct, mnats made a PSU board that supports dual 1176 configurations. You can wire two 1176's from that one PSU and use just the one transformer.

I don't think there's anything wrong with using two transformers, I'm sure the more experienced may disagree with me on that though.

Congratulations on your build regardless! I need to finish my 1176, still waiting on parts unfortunately  :-X

 

[mrfunk81]

Here you are my wiring:

r32 burn in 10 sec, I've 17V on BRN OT, 11V on WHT/BLK, 23V on Q6 base, 10,5 V across R32..

Does the voltage posted on the mnats document match if I use 2N3708??

Heeeelpppp!! Thanks

 

[Scrappersa]

Hey guys, I've been trying to wrap my head around this whole thread but I can't seem to find this anywhere although I'm sure many people have had the same issue. My Rev D (Rotary version with Mnat's Little PSU) is passing audio fine. The input attenuator and output seem to be working properly but the the output signal seems to spike occasionally when I turn it up OR down. The main problem that I'm having is that the actual unit is not compressing. GR mode on the VU meter doesn't show anything happening as well but +4 mode shows the signal just fine. Does anybody know where I should start looking? Been troubleshooting this thing for the past few days to no avail. I'll get some pictures up if it helps.

 

[telefunk]

Hey guys, I've been trying to wrap my head around this whole thread but I can't seem to find this anywhere although I'm sure many people have had the same issue. My Rev D (Rotary version with Mnat's Little PSU) is passing audio fine. The input attenuator and output seem to be working properly but the the output signal seems to spike occasionally when I turn it up OR down. The main problem that I'm having is that the actual unit is not compressing. GR mode on the VU meter doesn't show anything happening as well but +4 mode shows the signal just fine. Does anybody know where I should start looking? Been troubleshooting this thing for the past few days to no avail. I'll get some pictures up if it helps.

More info of what you have tested by far would be helpfull...

But for starters check that the pad 22 does not connect to ground, that's bypassing the GR.

 

[Scrappersa]

I've just checked continuity on all of the wires to pads. Haven't checked any voltages yet except for the ones coming off the little psu which are fine. My pad 22 off the main board is running straight to pad 22 on the meter board. I didn't ground it.

Edit: Rechecked all of my wiring for the 20th time and it looks like my release pot was wired backwards on the board. I fixed it but now the compressor is going crazy. When I adjust the output pot, it makes a weird as oscillating sound and almost no signal is passing. The more I turn it, the more intense the sound gets. Would this happen to be a grounding error or does it sound like something a little more in depth?

 

[mrfunk81]

Why in your opinion?? The measure were made with the OT unplugged because when I plug it R32 burn and there is no time to measure..

 

[Scrappersa]

I grounded the output xlr to the case and the oscillating seems to have disappeared. Now it seems like the compression is working, but the compressor is sucking out all of the bass. Not sure why, but when I change the ratio back and forth, it seems to come back after a little while. It's being pretty intermittent.

Edit: Yeah, what could cause it to suck the bass out?

 

[Scrappersa]

Wow, I can build a freaking compressor but I can't wire a cable correctly. Just to give a heads up to anybody else who may encounter a compressor or piece of hardware that completely sucks the bass out (e.g. low cut/high pass filter/unintentional asshole), the problem was my input cable. I was running the compressor into my patch bay using an XLR to 1/4" TRS cable that was wired incorrectly causing phase problems. The compressor seems to be working correctly. I'm going to try calibrating it tomorrow and make sure that everything else is functioning correctly before I get my hopes way to high, but for now it sounds great!

 

[berkleystudios]

Wow, I can build a freaking compressor but I can't wire a cable correctly. Just to give a heads up to anybody else who may encounter a compressor or piece of hardware that completely sucks the bass out (e.g. low cut/high pass filter/unintentional asshole), the problem was my input cable. I was running the compressor into my patch bay using an XLR to 1/4" TRS cable that was wired incorrectly causing phase problems. The compressor seems to be working correctly. I'm going to try calibrating it tomorrow and make sure that everything else is functioning correctly before I get my hopes way to high, but for now it sounds great!

haha i have made that simple mistake a few times. i blew an avalon 747 before i found out too