11

EQP501 Passive Equalizer / Re: Son faible et pas d'EQ

« Last post by JPK on October 06, 2025, 09:23:29 AM »

Merci pour votre retour. À ce stade, c’est notre premier cas de défaillance sur ce modèle de switch parmi plusieurs milliers d’unités livrées, d’où notre étonnement.

Pour affiner le diagnostic, pouvez-vous confirmer s’il n’a pas pu être altéré lors du montage ou d’une manipulation ? En particulier :

• Contraintes mécaniques : Choc, effort sur l’axe/capot, torsion du levier, mauvais alignement avec la façade.

• Thermique/soudure : échauffement prolongé (> 3–4 s par patte), reprise multiple.

Selon ces éléments, on confirmera rapidement s’il s’agit d’un défaut pièce ou d’un incident de montage.

12

EQP501 Passive Equalizer / Re: Son faible et pas d'EQ

« Last post by Pierro on October 05, 2025, 08:38:36 PM »

Bonjour, 

J'ai donc envoyé le kit à reparer, cela venait du switch SW3 qui était defectueux. 
Maintenant l'EQ marche correctement. J'ai vu dans un autre post que si le probleme venait d'un composant defectueux il ne fallait payer que le transport, mais Fabrice m'a chargé 89€.

13

EQ573 Equaliser / Re: Ceramic Capacitor Issue

« Last post by cmcclellan on October 01, 2025, 04:35:33 AM »

Well what a silly mistake on my part! I dumped out the bag of capacitors and started organizing them by the marking on the front. I did not turn over the capacitors with the K1J and K2J markings... I snapped the picture once they were sorted and put them back in the bag. I was able to complete the build now, all of the ceramic capacitors were indeed included in both kits. Appreciate the help in figuring this out. Thanks. 

14

EQ573 Equaliser / Re: Ceramic Capacitor Issue

« Last post by fabrice on September 28, 2025, 08:56:16 PM »

Hi,

K1J (K2J)means :
K radial
1(2) voltage code
J tolerance
Did you rotate the capacitors with K2J or K1J? The references are normally written on the other side.

15

EQ573 Equaliser / Ceramic Capacitor Issue

« Last post by cmcclellan on September 27, 2025, 04:15:39 AM »

I ordered two EQ573 kits and just got around to building them. The two kits have different variations of ceramic capacitors provided. The issue lies in the ceramic capacitors 471 and 470. To be clear, the BOM states that you need five ceramic capacitors reading 470 (47p) and five ceramic capacitors reading 471 (470p).

The first EQ573 kit provided three ceramic capacitors reading 470, two reading 471, five reading K2J and one capacitor reading K1J. These are pictured below. There is nothing in the BOM reading K1J or K2J.





The second EQ573 kit provided three ceramic capacitors reading 470, three reading 471, and then four reading K2J.
These are pictured below.


It seems I should have been provided five 470 ceramic caps and five 471 for each kit. Am I misunderstanding something with the other capacitors provided? Any clarification is appreciated. Thanks.

16

MU524 Vari-Mu Tube Compressor / Re: Stuck on step 7

« Last post by soundguy937 on September 18, 2025, 06:48:38 PM »

Thanks a million, definitely taking notes on my mistakes.

17

MU524 Vari-Mu Tube Compressor / Re: Stuck on step 7

« Last post by JPK on September 18, 2025, 05:48:33 PM »

Hello, your module is repaired.
There were two problems.
The first was the broken 2n7000 (be careful of static electricity, this component is very sensitive) and the second was the defective solder on the tube's PCB. I think the solder you're using isn't the best quality for proper soldering. I noticed some residue due to the solder. The connection to the tube wasn't perfect (there was noise in the tube and the tube's balance voltage was impossible to achieve).

The module has been calibrated and reassembled. It's ready to use!

18

MU524 Vari-Mu Tube Compressor / Re: Stuck on step 7

« Last post by soundguy937 on September 18, 2025, 04:39:22 PM »

My unit should have arrived late last week. Do you have an eta when you or your staff will be able to take a look at it?

19

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

« Last post by JPK on September 16, 2025, 05:50:42 PM »

The L272 has become difficult to find these days.
You can replace it with a TCA0372DP1.
Like any other integrated circuit, it can be killed by overvoltage on any pin, a short circuit on some pins and by overheating.

20

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

« Last post by mrevans on September 15, 2025, 09:01:37 PM »

Thanks for the fast reply! I followed your instructions, and I can measure 12V between V- and TP8 and 225V between 0V and TP2 on both units. 
I will replace the U4 on both of them and let you know if they work fine now.
They both failed at the same time. I think it was a problem related to the 500 Rack PSU where  I had mounted them. One voltage rail was having problems.
I do not think they overheat. In your experience, what is the most common failure cause of the L272?

Cheers. 
Jorge