[BUILD] 1176LN Rev D DIY

[muffy1975]

Team REV D ;D,

What is the effect of having 22k instead of 25k on the attack potentiometer?
What is the effect of having 220K instead of 250k on the output potentiometer?

has anyone got a few of those 25k linear SPDT pots for sale in England/Europe/UK? Or can order a few more if they are putting in an order and sell them on to me?

What is the fastest someone has put one of these REV D's together ( saying you have a precut 2u case ) ?

PACE

Michael

XOX

 

[dmp]

Anyplace I can buy a faceplate?
Do folks build faceplates?

 

[RedNoise]

Try to check echonorth , hairball shop ...

 

[Stagefright13]

Changing the pot values slightly like you suggest Muffy will be no problem. But changing the input tpad will certainly cause problems. Best to get the t-pad from hairball if you want it to work correctly. I didn't use the switched attack on any of mine. I just wired it to the off pushbutton. So I didn't run AC to the faceplate cause I am paranoid... But I gave my friend a switched attack pot and is working great for him.

John

 

[ilfungo]

hello
it is normal that the compressors have a lot 'of noise (shhhhhh)?
the problem may be that I connected to a tac scorpion  inserts unbalanced?
sorry for my english....

 

[bdubya]

Yeah, I get that if i feed it an unbalanced input.  It amplifies the open pin 3 (ssshhhhhhh) along with the hot pin 2.  Use it on a balanced buss, instead?  It should be quiet as a mouse when it gets a balanced signal, though, or somethings up  . . .

bw

 

[canidoit]

hello
it is normal that the compressors have a lot 'of noise (shhhhhh)?
the problem may be that I connected to a tac scorpion  inserts unbalanced?
sorry for my english....

The Rev D is pretty quiet from my experience. I am using balance XLR connections. People here have commented on how quiet this build is on theirs.

 

[ilfungo]

my problem is that the Tac Scorpion inserts unbalanced ..

another question

I must  measure the voltage -10
with all the controls connected (ratio board, meter board)?
whether the measure before connecting everything -9.5
If you measure with everything connected -8.6
correct?
Thanks

 

[ilfungo]

I have solved a problem
I have changed r81 1K with 560 R and the negative tension is now ok
can this create a problem?
Thanks

 

[spacecho]

Hello Guys!

Im building a pair of these and using the mnats power supply board - i noticed that the wonderful boards mako made (12.05.08) have a marking for +30 at the left side of where R87 (1.1k 1 watt resistor) would go, and -10 at the right side of where CR6 (in4740 diode) would go.

I'm assuming these points are where i would send the +30 and -10.
I want to use the terminal blocks at the edge of the board (where power would normally be routed from the torrodial transformer)

My question is: do i jumper from the base of where CR7 and CR8 / CR10 would be? to the respective voltages points mentioned earlier?
as far as i can tell from the schematic and looking at the pcb (black is hard to see) these pads on the pcb would be a direct link to the power transformer and not connected to anything else (as long as the onboard power parts are ommited) so it should be ok?

Sorry if i'm not explaining this well - i've read through the entire thread and didnt see a mention of this - mako's site has a picture of a rev G board with jumpers on it - bet they are in different places and i thought it better to ask,

 

[muffy1975]

Spaceho,

you have the right idea. +30 needs to see +30 and -10 needs to see -10V.

Use a continuity function on your multi meter to connect the header points on the circuit board to the +30 and -10 destinations. Most people use a cut to size piece of wire or the leg of a resistor.

Muffy

 

[bdubya]

nevermind, I thought you were using the onboard P.S. . . .

 

[Ringwraith]

I'm at the same point but using the main boards PS. Just got the Power Supply parts stuffed & want to check & make sure all things are go before continuing. I'm curious if I need to ground the board?? After stuffing all the parts in the PS block, I don't thing the board itself is grounded yet.

Also do I just use one set of wires on the primary side for 115V? (Canada)
Then tape up the other two?

Thanks
Sean

 

[bdubya]

The ground occurs through the center tap connection on the edge of the board where you're connecting your AC off the power transformer.  Look back through the thread, and on mnats' page, there's a diagram for wiring up the primary properly for 115V. 

bw

 

[williamjf77]

hello im new to this forum but im in a bind this may sound dumb but i have mnats rev f board ind can't find where to wire the input pot?

 

[Ringwraith]

I'm a little confused about how folks are wiring the input XLR these days. Mnats wiring guide is using a different board & no T-Attenuator. I understand where the + & - wires go from the XLR to the T-Attenuator then Input trannie & finally the board but how do I run the shielding?? I have the latest main board from Mnats & the latest Input transformer board from Hairball. Also the latest T-Pad from Hairball. Do I just connect the ground pin on the XLR to the case then run a connected shield to the T-Pad/Input transformer/main board & leave it unconnected along the way??

Thanks
Sean

 

[Moolason]

That looks very nice，It's a work of art!!! 

 

[ilfungo]

Ciao
I have made 2 REV D and
sounds very nice!!!
It's possible to make another REV d - OEP input and output ?
Thanks

 

[Ringwraith]

Just fired up my build last night & it worked right off the bat! Woohoo!!
Sounds awesome & is compressing wonderfully. I also did the two Mnats video calibrations without problems.

I have a couple minor issues I'm trying to track down, maybe someone can help?

My Ratio buttons are reversed. I get 4:1 when 20:1 is pressed & 20:1 when 4:1 is pressed.
I wired the Ratio board up the way it says in my Hairball kit instructions. I've triple checked & all "looks" well but obviously I'm missing something.  :-\

Also I have the SPDT attack switch & wired it up the way the Hairball kit says to. I see in other posts & diagrams they use the a shielded wire & connect into it but there is no mention of this in Hairballs instructions. I'm not sure if Hairballs Ratio board eliminates the need for this or what but I'm not connecting into the ground pad beside 22. The switch cuts off compression but the meter still shows it.

Any thoughts?

Thanks
Sean

 

[Echo North]

Just fired up my build last night & it worked right off the bat! Woohoo!!
Sounds awesome & is compressing wonderfully. I also did the two Mnats video calibrations without problems.

I have a couple minor issues I'm trying to track down, maybe someone can help?

My Ratio buttons are reversed. I get 4:1 when 20:1 is pressed & 20:1 when 4:1 is pressed.
I wired the Ratio board up the way it says in my Hairball kit instructions. I've triple checked & all "looks" well but obviously I'm missing something.  :-\

Also I have the SPDT attack switch & wired it up the way the Hairball kit says to. I see in other posts & diagrams they use the a shielded wire & connect into it but there is no mention of this in Hairballs instructions. I'm not sure if Hairballs Ratio board eliminates the need for this or what but I'm not connecting into the ground pad beside 22. The switch cuts off compression but the meter still shows it.

Any thoughts?

Thanks
Sean

Your ratio's are probably correct.

The 4:1 ratio has a lower threshold then the 20:1 ratio.  As you increase the ratio (4 to 8 to 12 to 20) your threshold gets higher, which means with the same signal you will see less and less compression on your meter as you move from 4 to 20.  

Looking at the meter is a little misleading.  Check out gswan's explanation of ratio and how to measure it here:
http://www.axtsystems.com/index.php?option=com_content&view=article&id=54:1176lnratios&catid=34:1176ln&Itemid=62

The shield you are seeing on the switch is the signal ground connection.  The bypass switch disables GR when pad 22 is shorted (connected) to ground.  You can get the ground from a shield connected to ground or anything connected to ground.  When pad 22 is shorted to ground you should not see compression on your meter.

Thanks,

Mike