Tc electronic stereo chorus flanger low volume problem with mono output

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Nicale19
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Post by Nicale19 »

Howdy

I would need help to understand if this pedal that was sold to me, has or not a problem
Basically if I connect in a series guitar amp effect, the mono output has a fairly low volume.
If I plug in the output next to stereo, the volume is ok.
There is a pronounced decrease in volume both in bypass and with the pedal on, the trimmer gain compensates for this drop.
But, as mentioned, the volume on the stereo input is ok.

In case I connect the pedal in loop instead everything seems ok.
The volume and emphasis of the effect are optimal.

I do not understand if it is defective or if it is really so.
I have control values on the pcb, especially the Dual op4558.. And everything looks ok..

I don't know.. Tips?
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Lani
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Post by Lani »

Hard to say if this is the same circuit as the older version. May be able to trace it if you can get a shot of the other side of the board at the same angle and distance you took the first photo at. Not sure how hard it would be to get it out though so that would be your call if you want to attempt to get it out. Jacks and pots should be easy enough but it looks to be mains powered still so make sure there are no caps with charge still on them by measuring them with a meter, and if so, discharging them with a 100k resistor to ground. If you don't feel confident doing this then I would not attempt it because you may do more harm than good (to the pedal or yourself).

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Nicale19
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Post by Nicale19 »

Lani wrote: 30 May 2023, 14:20 Hard to say if this is the same circuit as the older version. May be able to trace it if you can get a shot of the other side of the board at the same angle and distance you took the first photo at. Not sure how hard it would be to get it out though so that would be your call if you want to attempt to get it out. Jacks and pots should be easy enough but it looks to be mains powered still so make sure there are no caps with charge still on them by measuring them with a meter, and if so, discharging them with a 100k cap to ground. If you don't feel confident doing this then I would not attempt it because you may do more harm than good (to the pedal or yourself).

Hi thanks for the reply
On the security of the device no problem, I tried to open it but without insisting I'll try again later
Ideally you have any idea what it could be?

I wrote to the musictribe technical support that adeso manages tc electronic and they told me to take it to an authorized center. Useless answer

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Nicale19
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Post by Nicale19 »

No solution or suggestions from music tribe

The sound, from the mono right output, comes out empty and low

Not bass in a problematic way intended as a grounded sound, but not full of harmonics like I would like to think
Even when switched off, sound is too thin..

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Nicale19
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Post by Nicale19 »

Do you think it is normal to have 6v on the mono output signal?

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deltafred
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Post by deltafred »

Nicale19 wrote: 07 Jun 2023, 04:26 Do you think it is normal to have 6v on the mono output signal?
You should have NO DC offset on the output signal.

Trace the output back. There will most probably be an electrolytic capacitor between the final opamp or transistor and the output. If this capacitor is leaky then it will not block the DC effectively.
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Nicale19
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Post by Nicale19 »

deltafred wrote: 10 Jun 2023, 16:10
Nicale19 wrote: 07 Jun 2023, 04:26 Do you think it is normal to have 6v on the mono output signal?
You should have NO DC offset on the output signal.

Trace the output back. There will most probably be an electrolytic capacitor between the final opamp or transistor and the output. If this capacitor is leaky then it will not block the DC effectively.

Thank you. It's my same thought Finally I disassembled the top I will try to check

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Nicale19
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Post by Nicale19 »

deltafred wrote: 10 Jun 2023, 16:10
Nicale19 wrote: 07 Jun 2023, 04:26 Do you think it is normal to have 6v on the mono output signal?
You should have NO DC offset on the output signal.

Trace the output back. There will most probably be an electrolytic capacitor between the final opamp or transistor and the output. If this capacitor is leaky then it will not block the DC effectively.

Bingo!!

+1

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Post by Nicale19 »

This was the culprit
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IMG_20230617_210255.jpg
IMG_20230617_210554.jpg

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