SB4000 Support Thread

Can someone please repost the build manual, and schematic?
The dropbox link above is dead.  I want to see the calibration procedure.

I would really appreciate it!

Elegost said:

Can someone please repost the build manual, and schematic?
The dropbox link above is dead.  I want to see the calibration procedure.

I would really appreciate it!

Click to expand...

Bump!
I'd also appreciate a link...

I'd also appreciate a link to the build manual, if anyone's got it.

Me too (link to manual, please, thanks)... I'm finally finishing up this build, and can't find the build manual anywhere...  I emailed serpent, but nothing back from them (yet).

Guys,

Sorry not sure why the link was messed up.  It has been fixed.  If anyone else needs anything please email me at [email protected].  My schedule is a little crazy this week so might be a day or 2 before I can get back to you.

Could someone tell me how to mount the Quad VCA boards?? My kit had no pins or anything. I bought some op amp pins hoping that would work. But they are too big.

Or do I just use some trimmed leads left over?

Edit: Think i got it! Found some pins that i can use.

Seems I've got an extra 22k resistor here because I can't for the life of me find where this one's supposed to go! haha.

has anyone successfully put a crush-n-blend into an SB4000? if so, do you mind sharing were your tie-in points were
Thanks

Hi Guys

I have a problem with my power supply. I fired it up today making sure the molex connectors were NOT connected to the main PCB.

my AC voltages are good 240V for Australia. Here's the problem. My -12VDC  reads -19VDC which is very strange as all other DC voltages +12DC and + and - 15VDC are ok .... !!! 

I have to admit I accidentally put the regulators 7912 and 7812 in the wrong places then corrected them. Would this have caused a blown IC ? Mike from Oz   

ratty_7 said:

...My -12VDC  reads -19VDC ...

Click to expand...

a temporary load resistor (240R ... 1K) will show, if the regulator will behave correctly.

I have to admit I accidentally put the regulators 7912 and 7812 in the wrong places then corrected them. Would this have caused a fault in a cap or something...???? Mike from Oz 

Click to expand...

If you ever powered your device with the swapped places regulators, the 79xx won't survive this polarity reversed voltage feed, so it needs to get exchanged.

Hi Harpo,

Thanks for your quick reply.

I have replaced the 7912 and the 7812 with a new ones and put them in the right places, but I am still getting  -19DCV, when it should be -12VDC

All other voltages ok... Mike

ratty_7 said:

Hi Harpo,

Thanks for your quick reply.

I have replaced the 7912 and the 7812 with a new ones and put them in the right places, but I am still getting  -19DCV, when it should be -12VDC

All other voltages ok... Mike

Click to expand...

as already said, 'a temporary load resistor (240R ... 1K) will show, if the regulator will behave correctly.'
Without the rest of the circuit connected, the voltage regulator sees no load. The 79xx ones are a little more picky than the other. Just place a temporary resistor in range 240R up to 1K ohm for a 12...50mA load between the 0V and -12VDC connection (or across C151 or C152 for the same effect) in order to check if the vreg will behave correctly with load connected.

I want to buy the SB4000 board and front panel but I don't think it will be able to mount onto my par-metal 1U rack case. Can someone please inform me what is a compatible rack chassis? Will it be able to mount onto the circuit specialists 1U rack?

mattmartin831 said:

I want to buy the SB4000 board and front panel but I don't think it will be able to mount onto my par-metal 1U rack case. Can someone please inform me what is a compatible rack chassis? Will it be able to mount onto the circuit specialists 1U rack?

Click to expand...

I used a Par-Metal case when i built mine...

wave said:

I used a Par-Metal case when i built mine...

Click to expand...

My mistake, thanks for the verification!

Harpo said:

as already said, 'a temporary load resistor (240R ... 1K) will show, if the regulator will behave correctly.'
Without the rest of the circuit connected, the voltage regulator sees no load. The 79xx ones are a little more picky than the other. Just place a temporary resistor in range 240R up to 1K ohm for a 12...50mA load between the 0V and -12VDC connection (or across C151 or C152 for the same effect) in order to check if the vreg will behave correctly with load connected.

Click to expand...

Hi Harpo
Just thought I d say thanks for your help as I finally fixed the  all the rails and they now read +15-15  +12 -12  thanks again...
Mike from Oz 

Harpo said:

as already said, 'a temporary load resistor (240R ... 1K) will show, if the regulator will behave correctly.'
Without the rest of the circuit connected, the voltage regulator sees no load. The 79xx ones are a little more picky than the other. Just place a temporary resistor in range 240R up to 1K ohm for a 12...50mA load between the 0V and -12VDC connection (or across C151 or C152 for the same effect) in order to check if the vreg will behave correctly with load connected.

Click to expand...

Hi Harpo

I have a problem with calibration step 2.

1. I have put a 1k test tone at -5.5db =1.228 left ch to -5.5db - 1.236 right ch into the unit. The outputs back into the DAW.
2. I tried to adjust VR 1 and 2 but both adjustments have NO effect on either channel in the DAW ...any clues ..?

3. I then tried the alternative method using my Fluke True RMS meter and I was astounded that the left output ch read 1.224 AC volts  and the right ch a whopping 34 volts AC ...???

ratty_7 said:

Hi Harpo

I have a problem with calibration step 2.

1. I have put a 1k test tone at -5.5db =1.228 left ch to -5.5db - 1.236 right ch into the unit. The outputs back into the DAW.
2. I tried to adjust VR 1 and 2 but both adjustments have NO effect on either channel in the DAW ...any clues ..?

3. I then tried the alternative method using my Fluke True RMS meter and I was astounded that the left output ch read 1.224 AC volts  and the right ch a whopping 34 volts AC ...???

Click to expand...

You already read my reply #1117 from pg.56 ? Pg.62 might be useful as well.
Empty batteries in multimeters can give funny readouts, just an idea ...
good luck

Hi
I am having a big problem with Step 5 of the calibration of my SB4000
I have followed the instructions Ik test tone, adjusted the levels of my DAW to -10db. 
Adjusted the threshold on my compressor to 10db but the DAW did change to show -20db and also VR16 adjustment seems to have no effect.  Also the the attack and release seems to have a major impact on the output levels in my DAW.  Any help would be appreciated. :

I’ve had my SB4000 operating now for a little over a year but since day 1, I’ve had issues with the right channel being about 3dB louder than the left when running a signal generator through it. I figured it was close enough so I went ahead using it with the Trim plugin on my mix bus but think it’s time to get this figured out. Readings are the same with the compressor engaged or bypassed. Any idea as to what could be causing this loss to the left channel or where to begin to find the issue?  Thanks in advance.