21

MP566 Tube microphone preamplifier / Re: MP566 fault troubleshooting help needed.

« Last post by JPK on September 14, 2025, 04:39:05 PM »

The problem is on U4 or U5 or U6 or U7 or several of these.
Remove U4 and create a small jumper with a little piece of wire, between pins 2 & 3.
Place the voltmeter between 0V and TP2 and power on. If the high voltage is present then U5 is OK.
Remove the jumper and place anotherone between pins 1 & 2.
Place the voltmeter between V- and TP8 and power on. If the 12V is present then U6 and U7 are OK.
If both tests are OK, you just need to replace U4.

Did the 2 pres broke down at the same time? Did they overheat?

22

MP566 Tube microphone preamplifier / MP566 fault troubleshooting help needed.

« Last post by mrevans on September 12, 2025, 02:01:03 PM »

Hi, I have a pair of MP566 that I have used for some years, suddenly stopped working. I have followed the guides and read the forum for clues or maybe solutions. 
from the test guide
1. There is no short circuit on v+ or v- and GND
2. I get 0Vdc  when testing the High voltage between TP2 and 0V
3. On 1 unit the v+ is 15.9V and the V- is around+7V, on the second unit  the v+ is -6.5V and V- is-16V. 
4. The current consumption on the rails is 400mA on one and 30 mA on the other. 
5. I read in one of the threads to remove U1 U4 and the Tube   to check if the V+ rail and V- rail would get +16 V and -16V respectively.  I removed U1, U4 and the vacum tube on both units and  I do get +16V on V+ and -16V on V- . 
6. I am looking for the next steps to follow since on the other threads there was another issue. Regarding a reversed diode.

Thank you! Please let me know what other tests should I do. I am suspecting that either U1 or U4 are damaged, but how to test that?. The revision of the board I have is 1.5
BR Jorge

23

Discussions about the products / Re: Christmas wish-list new modules suggestion!

« Last post by JPK on September 09, 2025, 11:39:45 AM »

Thank you for the clarification.

24

Discussions about the products / Re: Christmas wish-list new modules suggestion!

« Last post by Lud on September 08, 2025, 06:57:07 PM »

And a U47 or 48

25

Discussions about the products / Re: Christmas wish-list new modules suggestion!

« Last post by Lud on September 08, 2025, 06:55:18 PM »

For the widener i don't like the plugin i use, it works but it does not sound pleasent to my ears. The idea is using my comps for mix bus and to have the widener with it in the analog path. It does not need to be very complex with a lot of features so it could be not much expensive. Beeing able to center the low end would be super cool though, and M/S.

The limiter it's a bit tricky cause i have a free plugin that is stunning so i don't need one but if it can be added to a widener and works as amazingly as my plugin it would be tremendous.

I already have two CP5176 and two MU524, they sound super cool but matching them is not super easy, plus a stereo comp should be less expensive maybe. I would be more on the stereo fet.

I would love an analog chorus that i can use with my guitar or for mixing. I have no valuable reasons for that but i would pull the trigger for a pair.

A 10 slots lunchbox with faders pan and aux sends in differents racks 

Some 19 racks (everything tubes)

Also maybe some other kind of products like a bass head amp (solid state first), guitar head amps...

26

Discussions about the products / Re: Christmas wish-list new modules suggestion!

« Last post by JPK on September 08, 2025, 05:48:30 PM »

Thank you for these suggestions, they are much appreciated. We are constantly thinking about what the next module should be.

Stereo width module: already considered. What do you think would be the advantage of analog over plugin?
Stereo fet compressor: It is already available in the form of 2 CP5176. Same thing with the varimu.
Analog chorus: Really? This would also needs a stereo module. Would you use it on stage or in the studio?
Analog delay: I think the best delays are digital (like Eventide).

27

Discussions about the products / Christmas wish-list new modules suggestion!

« Last post by Lud on September 08, 2025, 05:04:27 PM »

Here is a list of modules i wish!

 - A stereo width module, with the ability to center the low end, something like the TK audio M/S station maybe with a limiter added and the possibility to switch before or after.

- A stereo fet compressor would be pretty cool. (a varimu stereo comp too)

- A analog chorus, something like the Pope audio dirty C would be super cool.

- Maybe an analog delay too.

Cheers!

28

MP573 Microphone preamplifier / Re: Loud Pop When Changing dB Rotary Switch

« Last post by musicarr on August 30, 2025, 05:01:28 PM »

Got it. I know what to get for the C20, then. Thanks.

29

MP573 Microphone preamplifier / Re: Loud Pop When Changing dB Rotary Switch

« Last post by JPK on August 30, 2025, 09:12:22 AM »

10% tolerance is enough for these DC removing tantalum caps.
Electrolytic aluminum caps are generally 20%.
Ceramic and film are 5%, 10% or 20% depending on their role.

30

MP573 Microphone preamplifier / Re: MP573 LED not behaving correctly

« Last post by JPK on August 30, 2025, 09:04:49 AM »

It does make sense!
What we do is remove the cover of the XLR plug to access the pins and connect the meter to them.