Question about Lexicon MC-1 Amplifier

1 Answer

Volume has started to fade

I have a Lexicon MC1 which has been working fine for the last 6 years. it was properly setup by a specialist. Recently the volume has started to drop to zero on its own accord and has to be put back up manually. Other times when watching movies the sound goes all fuzzy and the only way to hear anything meaningful is to put it on 2 channel. DTS, THX 5.1, 7.1 all sound awful. Any ideas?

Any assistance would be greatly appreciated.

Thanks,

Danny

Posted by on

  • DannyPara May 29, 2008

    robotek,

    Many Thanks for the prompt response. I have access to a good solderer but how will I know which joints need re-soldering? I haven't opened up the case yet to take a look but I can guess that there will be a lot of electronics in there.

    Many Thanks again,

    DannyPara


  • DannyPara Jun 02, 2008

    robotek,

    Many thanks for taking the time to assist me. I still need to find the time to get the unit to an Electrician in order to get the soldering done. I will report back once that has been completed.

    Your help is greatly appreciated.

    Danny




×

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • Master
  • 1,512 Answers

HI DannyPara


If the problems are intermittent, then the amp will most probably be suffering from dry solder joints. This is not uncommon about power devices in the unit like output stages and power regulators. I suggest that the amp needs to be checked over for such problems, and where needed resoldered to bring it back to a reliable state. If you are a gun with a soldering iron, you could do it your self. For this sort of work, I prefer to use solder with a 2% silver content as it produces a mechanically stronger soldered joint, and has a higher resistance to failure from the rigours of heating and cooling that constantly happens in amplifiers. If you think you dont have the skills required(good quality soldering is an practiced, and aquired skill), then get it into a decent repair guy for some attention. If you dont fix these problems,new faults may manifest themselves, and even expensive failures to output stages if left unattended.

Happy to answer any other questions you may have about it, just give me a hoy :) Thanks for using FixYa, If you consider the advice I have given you as sound, a FixYa rating is a great reward for my efforts to help you. Cheers.

regards
robotek

Posted on May 29, 2008

  • Graeme Ross
    Graeme Ross May 30, 2008

    I would start with the power supplies, and audio power output stages. Any area that has has heatsinks, or where browning of the PCB is occurring, or just plain suspect looking joints. I also like to spend some time thouroughly inspecting the soldering of the PCB's under good light.

    I have a term that I use to describe this sort of work. BLANKET RESOLDERING. Pretty much means resoldering everything that may need it, or even not need it. Failing solder joints can be very difficult to find with the eye. You can often test for these sorts of problems by heating areas with a hair blow dryer(dont get too carried away with the heat), and then gentle repetitive tapping of the PCB in that area may help to locate the section that is contributing to the problem, and help to prove that you have indeed fixed it. The same percussive technique can isolate the problem whilst the unit is actually faulting also. Good Luck :) Let me know how you go. :)



    regards

    robotek

×

Add Your Answer

Uploading: 0%

my-video-file.mp4

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

×

Loading...
Loading...

Related Questions:

1 Answer

Cracking noise of Lexicon MC12HD


replace your hdmi cable between tv and preamp...lemme know if it works.

Feb 17, 2014 | Lexicon Amplifiers & Preamps

1 Answer

I am using a Lexicon CX-7 Power Amplifier in conjunction with a Lexicon MV-5 Processor. I have 7 B&W Speakers (2 Fronts, 2 Sides, 2 Rears and one Center). I also have a REL Stentor III subwoofer....


I assume you're wrestling with the choice of using its onboard amp fed by the MV-5 or driving it from the CX-7's unused channel.

Of course either way will work. I'd go with the preamp-to-REL method as the REL engineers undoubtedly gave some thought to the amp design for the price paid.

Attach it to the Sub1 Preamp out

http://www.retrevo.com/support/Lexicon-MV-5-Receivers-manual/id/22990ci271/t/2/

Dec 25, 2010 | Lexicon CX-7 Amplifier

1 Answer

Stereo Amplifier fades out. My Sansui dolby pro


No that's how to describe a problem, folks - with details. Using internal FM as the source is always the preferred way of troubleshooting system-wide receiver audio problems (no cables or setting in the way).

Does the sound come on immediately with power and then fade or is there a small delay while the electronics stabilize, a click and then sound that fades?

The fizzle probably means something is rapidly overheating or a capacitor is malfunctioning. If both channels do it, I'd suspect a common power supply problem. Can't help much more than that.

Dec 12, 2009 | Amplifiers & Preamps

1 Answer

The machine constantly switches off, goes to standby or simply freezes mid use. It got so bad that eventually it just wouldn't power up. It's been back to Lexicon twice - recently they replaced the the...


I have access to the Lexicon service guys, but will need a bit more info to assist in tracking this down.

1) Have you noticed any pattern to when the unit fails. In other words, does it tend to fail more readily after being on for a while, or is it consistant in behavior regardless of time?

2) Does the volume level of the unit change the total time before failure?

3) If you uinplug the unit for 1/2 and try using it, does the behavior change?

Please update this with the answers and also, if you could post what has already been done by the service center, that would help as well.
At this point, I would be suspicious of hte 5V line and/or the microprocessor internal controls. I'll research this a bit and try to get you more details as well.

Thanks,
Dan

Nov 04, 2009 | Lexicon RV-8 V2.0 Amplifier

1 Answer

My su g90 shuts off when i turn it up loud what do


Amplifiers get hot. The more you crank the volume up (or use extended for extended periods), the more current is required. When it gets hot, there is a fan motor (on the back), that should turn on. I believe your fan motor (brush) is worn out and therefore non-functional. Under this condition when the system overheats, it automatically changes mode to protect circuits.

Also note: if it works when you initially turn it on (cold) for a few minutes it should work fine...until it starts getting hot inside the case.

Oct 20, 2009 | Technics Amplifiers & Preamps

1 Answer

Amplification does not work


It sounds like a source slecton issue. Try the following and if that does not help I would start with a simple stereo setup and source and work up from there.

The RV-8 is powered on, but there is no audio.
1. Make sure volume level is audible. Volume level can be
increased with the front-panel volume knob or the remote
control VOL �� and �� buttons.
2. Make sure audio has not been muted. The message “MUTE
ON” or “FULL MUTE ON” will appear in the on-screen and
front-panel displays when audio has been muted. To deactivate
mute, press the Mute button or adjust the volume level.
3. Check the INPUT SETUP menu DIGITAL IN and ANALOG IN
parameters to ensure the appropriate audio connector is assigned
to the selected input.
4. Make sure the RV-8 is receiving an audio signal. To do this,
follow the instructions that begin on page 2-29 to open the
STATUS menu for the current input source. Hint: (Use the "STAT2" Button on the remote.)

Apr 29, 2009 | Lexicon RV-8 V2.0 Amplifier

1 Answer

Lexicon RV-8 wakupe failure


Did you try this....

In the event of a power outage, the RV-8 will display a BROWN
OUT!! PRESS STANDBY message. To turn the unit on, use the
STANDBY button. For more information, see “POWER
MANAGEMENT” on page 3-3....

POWER MANAGEMENT ON, OFF

"Setup" >> "Power Management"

Opens the POWER MANAGEMENT menu, which is used to automatically
put the RV-8 into standby mode during brownouts.
When set to ON, the RV-8 detects low voltage levels or a momentary
loss of power and puts the device in standby mode. In the event of a
power brown out, the RV-8 will display a BROWN OUT!! PRESS
STANDBY message. To turn the unit back on, use the front panel
STANDYBY button.

When set to OFF, the RV-8 will attempt to function during a
momentary power loss, however software settings may become
corrupt and need to be reset.
When the RV-8 is in standby mode, pressing the button turns the
unit on and activates all zones that were active in the previous
operating session.

The RV-8 does not power on.
1. Make sure the rear-panel power switch is set to the | (“on”)
position.
2. Attempt to power on the RV-8 with the front-panel Standby
button and remote control On button.
3. Examine the power cord to ensure a good connection between
the rear-panel AC input connector and the wall outlet.
4. Check the electrical circuit and breaker.

Apr 05, 2009 | Lexicon RV-8 V2.0 Amplifier

1 Answer

Help for AVR - 688


check the following1-no headphone jack is inserted.
2-check power cord firmly connected.3-if you have any doubt in remote change the battery with fresh new one4-unplug the system from power and replug it.5-check your volume level maybe it is in low level.-setup your speaker again.6-check speaker cables disconnection-7 -check that mute button not pressed.

Jul 12, 2008 | Denon Amplifiers & Preamps

1 Answer

MC1 Switched Power Supply


Hi Hansjo. You may find that if one capacitor has failed, then there may be more. If you see any signs of bulging, leaking, or pushing the bottom out of any caps, then It is a good idea to just change them all. For the small expense, it is worthwhile knowing that your power supply has fresh caps. Try the amp and then see how it goes. If you still have problems, get back to me here and we can talk about it more.

regards
Graeme

Feb 28, 2008 | Lexicon MC-1 Amplifier

Not finding what you are looking for?
Lexicon MC-1 Amplifier Logo

168 people viewed this question

Ask a Question

Usually answered in minutes!

Top Lexicon Amplifiers & Preamps Experts

 Grubhead
Grubhead

Level 3 Expert

4584 Answers

Donald DCruz
Donald DCruz

Level 3 Expert

17129 Answers

The Knight
The Knight

Level 3 Expert

68229 Answers

Are you a Lexicon Amplifier and Preamp Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...