Question about Music

1 Answer

Problems with certain channels and there gain pots

I have a similar problem in the the gain for channels 6, 9, 12 and 16 all seem to have intermittent faults.
Channel six and nine seem to come back on after a gentle tap on the channel strip, 12 is a lower gain then the rest but is useable and 16 has a problem when you turn the gain pot past 11 o'clock - the level just drops.

Is this an issue that could be repaired?

Posted by on

1 Answer

  • Level 2:

    An expert who has achieved level 2 by getting 100 points

    MVP:

    An expert that gotĀ 5 achievements.

    Novelist:

    An expert who has written 50 answers of more than 400 characters.

    Governor:

    An expert whose answer gotĀ voted for 20 times.

  • Expert
  • 133 Answers

I assume you are talking about an audio mixer, here's what i think:

I'm not sure about channels 12 and 16, but channels 6 and 9 seem like having some loose solder contacts, which usually occur with long term use - you need to remove the problematic channel strips and check the solder contacts on any of the pots / switches / connectors that protrude through the top panel - resolder any loose or bad solder contacts (i usually resolder ALL pins on ALL connectors, pots and switches just to be sure).

As for the lower gain on CH12 - see if the mixing slider is connected via wires, if so, compare it to the connections on other channels, see if there is a loose wire or if the wires are connected in a wrong way (i had a "lower gain" issue with a mixer once that turned out to be a wrongly connected mixing slider - i obviously wasn't the first person to repair that mixer...)

Channel 16: check input preamp IC, could be a bad electrolytic filter capacitor or other components, possibly a faulty IC.

Hope some of this helps...

regards

3rq8 (Triarcuate)

Posted on Sep 08, 2009

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

How to replace a potentiometer


Disconnect from the mains.
Unscrew the four screws in the top
Slide out the chassis
Remove the knobs
Unscrew the pot nuts
Unclip/unscrew the PCB
Unsolder the pot
Solder in new one.
Re-assemble in reverse order
Strongly suggest you youse a better quality pot
Also the treble pot tends to go on these, replace at same time
All the best, Chris

Apr 14, 2013 | Marshall MG15DFX 15 Watt Compact 2...

1 Answer

Still have sound through speaker with channel B gain input set to OFF


This could be fixed checking/changing the vol pot of the "B" channel, also i would highly recommend to clean all back switches, including Stereo/Bridge switch, which it should be outwards to operate in Stereo mode, let me know if i can help more.

Jan 26, 2013 | Peavey PV 900 Power Amp

1 Answer

Power problems with my Peavey PV-1500


Suspect that the pot is broken, or start cleaning all the back switches, this pv amps suffer from a terrible switch quality.

Mar 15, 2012 | Peavey Electronics Peavey Pv 1500 Power...

1 Answer

The right output channel on the right side of my pmc 05 pro 4 has very low output. I can hear both right and left output channels in the headphones when I have the cue selected but when I try to monitor...


I assume you swapped thee output leads as well as the inputs which you di mention, to verify you amps and cables...
The Vestax schematic I have is NOT your same model, but the companies often re-use circuitry. In the schematic I have it appears that the two channels go through two levels of NJM2068L op amps.
In these two levels there is both a master gain control. It is important to know whether the gain control varies the output level of the right, even if it is low. Also in this gain control area is a master balance pot which varies the ratio of the left and right and is CAPABLE of taking either channel to near zero output... IF you have that control check it for sure !!! The pot is a dual employing both an A taper and C taper which is a reverse of the A.
The right tool for troubleshooting this is an oscilloscope, but first an inspection looking for board cracks around the output and pot area is in order.

Jan 01, 2011 | Vestax PMC-05PRO IV PMC-05 PRO 4 DJ MIXER

1 Answer

I just bought a used valveking 100 half stack and the 1st channel does not work, second channel works but seems to have a loose input jack as connection is intermittent and affected by wiggling the input...


Same thing... they probably broke both jacks. Sometimes the guts of the jack is broken and it doesn't appear to be broken but is broken internally. You may find broken solder on the pins to these jacks as well.

Note that the two input jacks have a different gain.

Here is schematic: http://elektrotanya.com/peavey_valveking_100_212.pdf/download.html

Dec 02, 2010 | Peavey Valveking Head

1 Answer

Line 6 AX2 212, Are all of the pots 10K Linear ( apart from the volume which is dual ) or are any Log pots? I have changed the pots for linears as I was suffering intermittent problems, the sound is back...


Given your description of intermittent problems, I would venture an educated guess that the problem was NOT the pots to start with. Usually pots will have a part number and you may find an "A" or a "B" indicating the taper.

Look for a circuit board crack in the vicinity of the guitar input section, especially near the pots. Use a BRIGHT led flashlight from opposite side of the board and inspect all solder joints around the input section.

Line 6 seems to play games with a "guitar sense" line that goes to the DSP so problems with that or a break in the circuit trace could cause the symptom.

Aug 22, 2010 | Music

1 Answer

The gain control no longer works on the clean/crunch channel. all other features work fine, whats wrong with my amp?


Hi there. Try re-soldering the control pot to circuit board connections. If not, use ohm meter to verify pot functionality. If bad, replace.
Thanks
Paul

Jul 10, 2009 | Marshall Mg100dfx 100-Watt Combo Guitar...

1 Answer

I need to know the value pots to buy for vol,bass


If you have the old pots look on the edge of the cans (metal backs) for the code. Take them to a good electronics supplier and they can match them or measure the resistance from each outside pin with all pins free of interconnection. You will also need to know the audio tapers. The supplier should be able to tell from the codes.

Jul 08, 2009 | Music

2 Answers

MG100HDFX Amp - crunch setting seems too loud


There are 2 channels, Which means there are 2 sets of knobs ... One for clean and one for crunch. Start out with a low master volume and set up the crunch, Then the clen and switch between the 2 and make adjustments until they match volume wise ... Then turn the master up.

May 12, 2009 | Marshall MG100HDFX 100-Watt Amplifier Head

Not finding what you are looking for?
Music Logo

Related Topics:

98 people viewed this question

Ask a Question

Usually answered in minutes!

Top Music Experts

Vito Vacirca Jr.

Level 2 Expert

140 Answers

yadayada
yadayada

Level 3 Expert

75744 Answers

kakima

Level 3 Expert

102366 Answers

Are you a Music Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...