726

CP4500 Stereo Bus Compressor / Re: Setup Help THRESHOLD potentiometer counter clockwise reduces the out ?

« on: September 01, 2021, 05:34:12 PM »

On step 4, TP13 does not show any DC, no matter where I have the pot.

7: +2.9V

TP13 and U21 pin 7 are connected together. Find out why the connection is broken.

727

CP4500 Stereo Bus Compressor / Re: Setup Help THRESHOLD potentiometer counter clockwise reduces the out ?

« on: August 30, 2021, 05:24:13 PM »

Are you numbering the pins like this?
Pin 8 should be +16V

728

LA502 Optical Compressor / Meter LED's low brightness

« on: August 28, 2021, 09:42:04 AM »

If you purchased your kit in 2021 summer and your meter is working normally but the LED's seems too dark, then you may have received a bad LM317LZ component for U10.
Indeed, we have received a batch of LM317LZ with about 14% of bad parts.
If this is your case, please send us a message on https://www.soundskulptor.com/en/contact.php and we will send you a new part.
I am sorry for the inconvenience.

729

TS500 Tape Simulator / Meter LED's low brightness

« on: August 28, 2021, 09:38:42 AM »

If you purchased your kit in 2021 summer and your meter is working normally but one (or both) row of 8 LED's seems too dark, then you may have received a bad LM317LZ component for U5 or U6 (or both).
Indeed, we have received a batch of LM317LZ with about 14% of bad parts.
If this is your case, please send us a message on https://www.soundskulptor.com/en/contact.php and we will send you a new part.
I am sorry for the inconvenience.

730

CP5176 FET compressor / Meter LED's low brightness

« on: August 28, 2021, 09:33:21 AM »

If you purchased your kit in 2021 summer and your meter is working normally but one (or both) row of 8 LED's seems too dark, then you may have received a bad LM317LZ component for U5 or U6 (or both).
Indeed, we have received a batch of LM317LZ with about 14% of bad parts.
If this is your case, please send us a message on https://www.soundskulptor.com/en/contact.php and we will send you a new part.
I am sorry for the inconvenience.

731

CP4500 Stereo Bus Compressor / Re: CP4500 Setup with XT500

« on: August 28, 2021, 08:43:36 AM »

Yes this is the easiest way.

732

DI503J Triple DI and Re-Amp / Error in capacitors C3, C7, C8 (ceramic instead of film)

« on: August 25, 2021, 11:07:11 AM »

Some early kits received by mistake ceramic capacitors instead of WIMA film for C3, C7 & C8.
Please let us know if it is your case and we will send you the correct 1uF film.

733

501 Single Host / Re: Noisey unit

« on: August 25, 2021, 09:35:42 AM »

This is not very likely because switching power supplies do not create hum noise generally.
The MP573 is very sensitive to radiated hum, that gets in through the input transformer.
Make sure it is not placed too close to a device with a power transformer, a light dimmer, mains cables.

734

MP573 Microphone preamplifier / Re: Replacement 2 colour LED

« on: August 18, 2021, 09:43:42 AM »

Yes, looks good.

735

TS500 Tape Simulator / Re: Question about TS 500 transformers

« on: August 17, 2021, 08:41:15 AM »

Yes it is safe but generally not needed because they are not long enough to touch the chassis plate.

736

CP4500 Stereo Bus Compressor / Re: High signal Output first channel

« on: August 17, 2021, 08:39:04 AM »

Of course, no problem.

737

CP4500 Stereo Bus Compressor / Re: High signal Output first channel

« on: August 16, 2021, 05:54:10 PM »

I am short of ideas, maybe it is time to send us the unit for a closer check?

738

CP4500 Stereo Bus Compressor / Re: High signal Output first channel

« on: August 15, 2021, 08:38:03 AM »

All OK except pin 1 which should be at 0V (actually floating).
Do you see any DC voltage on TP1?

739

TS500 Tape Simulator / Re: Soldering Positive voltage regulator

« on: August 15, 2021, 08:30:29 AM »

You need a good heat transfer from the iron to the component so, you must use a big enough tip on the iron. Avoid the needle type.
Then you must heat the regulator metal tab until the solder starts flowing nicely. If your iron is set to a 320°C temperature max, there is no risk of overheating the component.

740

MP566 Tube microphone preamplifier / Re: Gain is too low

« on: August 09, 2021, 04:56:57 PM »

the new one has a significant amount of less gain then my first one.

Try swapping the tubes between the units, in case one tube would be defective.

With the drive pot to max and level pot to min, send a strong sine signal (like 0.5VAC) to the input then measure the AC levels you get on TP1 for both units. Are they different?
Next, with both drive and level pots to max, lower the input signal in order to get no distortion on the output and measure the AC levels on TP3 for both units. Are they different?
Next, measure the AC levels on TP4 for both units. Are they different?

741

CP4500 Stereo Bus Compressor / Re: Cant Level Match Channel 2 - Measured Channel 1 voltages and some were off

« on: August 06, 2021, 09:28:19 AM »

In Step 5:

• TP4 goes from 0.060VAC to 0.190VAC 0 VDC 

You must measure the AC voltage.


What is the revision number of your PCB?
Check that your solder residues are not conducting : https://www.soundskulptor.com/forum/index.php?topic=4.msg4#msg4
In such a case carefully cleanup the PCB's with isopropyl alcohol.

742

MP599 Microphone preamplifier / Re: MP599 not working SK99 ok

« on: August 06, 2021, 08:55:36 AM »

Good news! Anyway, the MP599 should work with the XT500. Check the cable with the DMM in ring mode.

743

XT500 Lunchbox connector extender / Re: XT500 Test Pins

« on: August 05, 2021, 05:05:58 PM »

Yes it will be easier to make measurements (if necessary) with the pins.
The pins are inserted with the short, square section end first.

744

CP4500 Stereo Bus Compressor / Re: High signal Output first channel

« on: August 05, 2021, 05:03:08 PM »

With U2 to U5 and U6 removed what are the DC voltages on the 8 pins of U5?

745

MP599 Microphone preamplifier / Re: MP599 not working SK99 ok

« on: August 03, 2021, 10:18:21 AM »

IN:      VPP: 7,35V      Vrms: 2,56mV

These values are not coherent for a sine signal. Please check again.

TP2:
VPP: 12,9V gainswitch on high, varies with the inputsignal
Vrms: 4,19V gainswitch on high, varies with the inputsignal

These values look correct. Do you see the sine on the scope?

Do you see the sine on L1 (top pin)?
Do you see the sine across R24?

746

CP4500 Stereo Bus Compressor / Re: High signal Output first channel

« on: August 03, 2021, 10:01:12 AM »

I don't understand the picture you send.

Sorry, this is for revision 1.4.

You have DC on U6 pin7 (=TP2). It should be 0.
Remove U2 to U5.
The DC on TP2 should be back to 0.
Insert sequentially U2 to U5, checking each time the DC on TP2.
Is there one IC that causes the DC rise ?

747

CP4500 Stereo Bus Compressor / Re: Unable to level match Channel 1

« on: August 01, 2021, 08:48:26 AM »

I'd be interested if you have any thoughts on what occurred.

Sorry, I can't find an explanation without knowing your setup details.

748

CP4500 Stereo Bus Compressor / Re: High signal Output first channel

« on: August 01, 2021, 08:36:42 AM »

Check that there is no component lead touching the chassis plate.
Check you have the correct resistors in R106, R46...R53.
Can you report the DC volts on the 8 pins of U6?
Can you check with an ohmmeter in ring mode that the solder joints of the THAT2181A are all good, in case we missed some.
The connections are marked in red in the attached picture. Verify the continuity between the IC pins and the corresponding pads.
You will need sharp meter probes to do this.

749

CP4500 Stereo Bus Compressor / Re: Unable to level match Channel 1

« on: July 31, 2021, 08:19:00 AM »

Your levels are good on TP2 so the issue must be in the output stage.
Check value, direction and solder joints of U7, BR2, RLY1.
If OK, try the other THAT1646 in U7.

750

CP4500 Stereo Bus Compressor / Re: Meter and IN switch light ossilating

« on: July 29, 2021, 08:14:12 AM »

I foud that R24 reads .815R

Set the attack to 30 and redo the test. It should read good.

Replug the front PCB but unplug the meter. Does it work?