One speaker quieter than the other

I'm new to these forums and I have a very limited knowledge of audio equipment. I have a ten year old Cambridge A1 amplifier, linked to a Marantz CD player of the same age and Cambridge Monitor Audio speakers (which were bought just before Christmas). I have noticed that the sound coming from the left speaker is lower than that coming out the right. At first, I thought that it must be the speaker itself, but when I swap the speakers over the speaker that was previously louder (i.e. the one on the right) is quieter and the one that was quieter (i.e. the left) sounds fine on the right. I have bought new cables but the problem persists. I took the amplifier along to a Hi-Fi guy today but he insisted that it must be the speakers and he wouldn't even look at the amplifier.

I don't have access to another amplifier to test my speakers. Any suggestions or ideas would be gratefully received. I can still listen to music as long as I turn the volume up on the left (quieter) speaker and 'even' out the sound. Obviously, this isn't an ideal situation though.

 

Have you switched cables for the CD player? Or just the speaker wire?

 

I have tried putting the CD cables into the Tuner inputs but the same thing happens. I have also tried selecting the phono option and playing a record through it but once again the sound is still imbalanced.

 

Just an easy thing to check and confirm...be sure the balance is centered (or level controls match). A balance control with a center detent may need to be "worked" occasionally on older gear as it can get a dead spot briefly, from dirt, smoke, or oxidation inside.

 

does the amp have a headphone out ?

 

Have you tried cleaning the pots with contact cleaner? Are they scratchy at all when you adjust the volume or balance?

 

Are the speaker cables the same length? I had a friend with this problem (more than 30 years ago) and the solution was the speaker wires. He was using VERY thin wire. The longer wire was attenuating the signal so much more than the shorter wire that the sound was unbalanced. We replaced the wire with equal lengths of "zip" cord and the problem was gone.

 

No. The headphone socket is on the CD player.

 

TH

No, I haven't done that yet. I will try it though, thanks. There is no scratchiness. The volume is just low. If I turn the volume up on the left speaker the dial just needs to be turned more to get a reasonable volume.

 

The wires are different lengths, but this didn't pose a problem with my previous speakers (which I replaced before Christmas because one of them died completely).

 

I think the problemi could be your room or incorrect position of your speaker. Corners, forniture etc. can increase or decrease volume. Try to find the best position.

 

If I understand you correctly you physically switched/moved the two speakers?
Moved the right speaker to the left side and left speaker to the right side?

If that is correct I would like you to try this test.

1) Make sure you have the phase/polarity of each speaker wired correctly from the amp's speaker left and right channel speaker terminals to each of the speaker terminals.

The speaker wire you are using should have some method of wire identification. Example, different insulation colors for each of the two wires. Like black and red.
Make sure you have the speaker wire connected to the Red color binding post on the amp, connected to the Red, + , binding post on the speaker. The other speaker wire connected to the Black color binding post on the amp to the Black binding post on the speaker. BOTH speakers must be wired the same. In Phase.

If wired wrong, correct the wiring connections. Listen to your system.

If you have them wired correctly then try this,

2) Switch the speaker cable wires on the back of the amp. (Only at the back of the amp)
Move the right speaker cable wires from the right channel binding posts of the amp to the left channel binding posts of the amp.
Move the left speaker cables from the left channel binding posts of the amp to the right channel binding posts of the amp.
Make sure you observe the correct wiring polarity for each speaker.

This test separates the output of the amp from the, speakers, speaker placement, room acoustics, and speaker wire conductivity issues.

Check for results. Is the right speaker now the lower level sounding speaker?

Post back your findings.

http://www.testfreaks.co.uk/stereo-amplifiers-receivers/cambridge-audio-a1/

 

First of all, many thanks for taking the time to help me with this. I checked the polarity and it was correct, so I moved onto your second suggestion (switching the wires at the back of the amp). When I did this, the right speaker (the one that was previously louder) is now quieter and the left speaker (the one that was originally quieter) is now louder. In effect, the problem has reversed. Does this tell us where the problem might be?

 

Sure does, your integrated amp has a problem. Take it to a different tech.

 

Good chance F1nut is correct.

You have narrowed down the problem.
Your test tells you speaker phasing is correct.
The speakers are not the problem.
Speaker placement or your room is not the problem.

Because in one of your posts you said you experienced the problem whether the front end source was the Marantz CDP or the TT. BUT, to be 100% sure it is not caused by a front end source or the interconnects that connect it to the Cambridge A1 I would suggest a simple test. Just reverse the interconnects from the CDP at the Cambridge A1 right and left inputs. (At the Cambridge A1 only) Take a listen. If nothing changed that rules out the CDP as well as the ICs.

One last test.
The speaker cables themselves.
Disconnect both speakers cables from the amp and speakers.
Reconnect the one that was on the right side on the left side.
Left side on the right side. (Observe phase polarity.)

Take a listen. If nothing changed the problem is the Cambridge A1.

Nicely explain to the repair tech the procedures you went through to eliminated everything else being the problem that lead to the Cambridge A1 being the problem.

 

Once again, many thanks for the advice. Nothing has changed when I reversed the interconnects. It would appear that it is as I thought and the Cambridge amplifier is at fault. Perhaps I hadn't explained this situation clearly enough to the tech so I'll give it another go. If it isn't economical to repair I will have to consider replacement which will be a real shame as I have had nearly a decade's worth of enjoyment from this system.

 

IF the speaker cables have terminations on each end like Banana or spades you also need to switched the cables to make sure 100% it is in no way a bad high resistive termination that is causing the problem. The connection could feel tight but still be highly corroded causing a voltage drop across termination connection. IME this would not only drop the volume level, the sound would suffer as well you hear from the speaker.
Now if you are just using stripped bare wire ends to connect the speaker cable wires, connected to the amp and speakers, then the test is not needed.
Jim

 

Yes, I just have the stripped bare wires. I can't even listen to music through headphones via the amp as the same thing is happening with the left channel (i.e. much quieter than the right). I've been quoted £40 just to diagnose the issue so I'm thinking that it might just be worth buying a new amp. I've had ten years out of this one.

 

You aren't likely to hurt SS gear if you drop it an inch or two on a hard surface. Unplug, lift, level, drop. See if it works properly then. A cold solder connection or oxidation in a connector may just respond to getting a micro-kick in the butt. Worth a try if done with care, especially if you are going to shelve it if you can't get it working.

 

i thought your amp does not have a headphone out ?
otherwise i would have suggested headphones to check if the amp is faulty.

 

That was a common fix for a Cambridge 840 integrated amp. Sometimes one of the relays that are used for the stepped volume control would stick screwing up the user's ability to control the volume of the amp. Only difference was the height the unit was lifted above the hard surface it was dropped on. If memory serves me right the distance was 3" to 4".
True story.

EDIT: On second thought, I think it was more like 2" or 3"

 

You're right, I should have added that I was listening through a headphone amplifier connected to the back of the amp.

 

well that pretty much leaves only the pre-amp stage in your amp as culprit. ( given you tried various sources)

 

Are the speaker wires equal length?

 

Not quite. One of them is about a metre longer.