SB4000 Support Thread

[sheadstedford]

Thats strange, my VU Meter only displays one bar at a time???? like 1 floating LED and not all of them at one like most led meters......is mine faulty?
I do kinda like the one floating LED though

 

[ruckus328]

Shead, you have it set for Dot Mode.  Remove JMP7 on the control board, or just cut it off - This will put it into bar mode.  Will draw 10x's as much current, but looks alot cooler.

 

[sheadstedford]

Realy, oh man....i really like the dot one.
Ill see

 

[sheadstedford]

so am i literally just cutting between the two jmp7 holes? im not quite sure

 

[jandoste]

Umit:

1) Your ribbon cable is backwards.  You have pin 1 on the main board going to pin 20 control board.  It needs to be corrected before we can continue.  Please verify the rest of you wiring polarities are correct.  Pin 1 is labeled on all connectors.

2) When in bypass does the unit pass audio?

3) I see all of the bargraph LED's are illuminated.  If you turn down the volume of your input signal, do the lights start to turn off?

Thanks Mike,
You are right it was  my ribbon cable !
So, I can say yopiiiiiiii youpppppupuupupupupiiiiiiii
It works 

 

[Ptownkid]

so am i literally just cutting between the two jmp7 holes? im not quite sure

I think he means to simply have nothing installed there...

 

[sheadstedford]

yeah there is nothing there at all.
Thats why i was confused. If there is nothing connecting JMP7 and its still only DOT mode, is it faulty? No probs if it is as i like it

 

[ruckus328]

yeah there is nothing there at all.
Thats why i was confused. If there is nothing connecting JMP7 and its still only DOT mode, is it faulty? No probs if it is as i like it

My bad - shead, umit, and everyone else - it's jumper INSTALLED for bar mode.

And shead, give it a try, trust me, you'll like it

 

[ruckus328]

Umit:

1) Your ribbon cable is backwards.  You have pin 1 on the main board going to pin 20 control board.  It needs to be corrected before we can continue.  Please verify the rest of you wiring polarities are correct.  Pin 1 is labeled on all connectors.

2) When in bypass does the unit pass audio?

3) I see all of the bargraph LED's are illuminated.  If you turn down the volume of your input signal, do the lights start to turn off?

Thanks Mike,
You are right it was  my ribbon cable !
So, I can say yopiiiiiiii youpppppupuupupupupiiiiiiii
It works 

Haha, easy fix.  Awesome!

 

[Adam Smith]

Ive about got mine built, however, I'm having a heck of a time getting my ribbon cable to crimp correctly. Is there a special tool I need to crimp these guys? I've been searching the forum for 45min and I remember reading something about this somewhere on this forum, but for the life of me, I can't find anything specifically about this ribbon. 

Any help is appreciated.

 

[sheadstedford]

Same here bro, in the end i just used pliers, be careful not to snap the brackets tho.
And rukus, thanks bro ill do that today and see what i prefer.
Tube drive works damn well as well!

About 75% done wit the mods, i found that the tube stage lost some low end in the signal so ive got an eq module to incorporate after to compensate for it.

Was thinkin of a tranny on output but maybe a little overkill.

 

[Rellister]

Adam,

struggled with these myself. A small vice did the trick for me.

tip from Ptown;

Yes, they need to be assembled with pure force. The best way to go about it (assuming you don't have a connector press, lol) is to use a vise or screw clamp to exert the pressure somewhat evenly.

Cheers

Rune

 

[ruckus328]

Ive about got mine built, however, I'm having a heck of a time getting my ribbon cable to crimp correctly. Is there a special tool I need to crimp these guys? I've been searching the forum for 45min and I remember reading something about this somewhere on this forum, but for the life of me, I can't find anything specifically about this ribbon. 

Any help is appreciated.

Vice or "C" clamp.  Should be a slam dunk with either.

Shead - what are the cap values on the output of your tube stage? 

Eq isn't going to do jack to boost frequencies that are no longer there.

 

[sheadstedford]

I bellieve they are 470nf

 

[Adam Smith]

Vice or "C" clamp.  Should be a slam dunk with either.

Great. Thanks!

 

[ruckus328]

I bellieve they are 470nf

I figured you were going to say somewhere around there.  This is too low for driving the input of the compressor.  The output capacitance of your tube stage into the 22K input impedance is creating a nice High Pass Filter.

You need to put a cap in parallel with each of the 470nF caps to increase the capacitance.  A 10uF or 22uF bipolar electrolytic cap should do the trick.  Or you can use two polarized electrolytic caps back-to-back.  Remember capacitance is halved when you put two caps in series, so if you use two back-to-back I'd go with the 22uF's for a total of 11uF.

Do this, your bass will come back.

 

[sheadstedford]

Your the man! Really appreciate your help with this bro!

 

[jandoste]

Thanks Mike for the great projects !

 

[sheadstedford]

I bellieve they are 470nf

I figured you were going to say somewhere around there.  This is too low for driving the input of the compressor.  The output capacitance of your tube stage into the 22K input impedance is creating a nice High Pass Filter.

You need to put a cap in parallel with each of the 470nF caps to increase the capacitance.  A 10uF or 22uF bipolar electrolytic cap should do the trick.  Or you can use two polarized electrolytic caps back-to-back.  Remember capacitance is halved when you put two caps in series, so if you use two back-to-back I'd go with the 22uF's for a total of 11uF.

Do this, your bass will come back.

So i literally just solder a 22uf cap to tje legs of the each of the 474 caps?
This is parallel right?

 

[snipsnip]

What degree are you doing?