[JustAudio]

Hi, my 14b has provided years of enjoyment. I recently upgraded my speakers and cables and since then noticed that the left speaker sounded lifeless compared to the right speaker. Switched the speaker cables around and this time the other speaker sounded lifeless as compared. I have not played around with all the different permutations to positively identify which is the culprit, but have a feeling it could be due to the power amp. May I know if there could be something wrong with the power amp? Sound I bring it in for to my dealer for service? I am using a bp25 as pre amp. Thanks..   

[Phil A]

Have you tried a mono recording to see if the balance on both is equal?  Is there a difference in gain settings on the channels?

[Phil A]

By the way - welcome to the forum.  Have you also tried different inputs on the preamp?

[brucek]

Hi, my 14b has provided years of enjoyment. I recently upgraded my speakers and cables and since then noticed that the left speaker sounded lifeless compared to the right speaker. Switched the speaker cables around and this time the other speaker sounded lifeless as compared. I have not played around with all the different permutations to positively identify which is the culprit, but have a feeling it could be due to the power amp. May I know if there could be something wrong with the power amp? Sound I bring it in for to my dealer for service? I am using a bp25 as pre amp. Thanks..

The test as you've described it indicates that the problem is following the cable.

You've been pleased with both left and right speaker (as you indicate), and you've been pleased with both left and right power amp channel (as you indicate).

Suspect one cable.

brucek

[1ZIP]

What did you do again....you swapped speaker cables from left channel to right channel and the problem moved to the right channel.  Or did you connect the left channel to the right speaker and the problem went to the right speaker? 

[JustAudio]

Realised there was something wrong in my description above, so I'll try again. I switched to mono on the pre amp during the test and used the balance to compare the left and right speakers. In each of the below case, there is only 1 change made from the normal configuration.

Base Case: Normal Configuration
Result: Left Speaker lifeless compared to right speaker

Case 1: Changed preamp inputs
Result: Left Speaker lifeless compared to right speaker

Case 2: Changed RCA input on power amp from left out (on pre amp) into right in (on power amp):
Result: Right Speaker lifeless compared to left speaker

Case 3: Changed RCA input on pre amp from left out (on cd player) into right in (on pre amp)
Result:  Left Speaker lifeless compared to right speaker

From the above, I kind of eliminated the following as the culprits
- Speakers
- Speaker cables
- pre amp inputs

I do not think cables are the problems as they are new. Could there be something not right with the pre/power amp?

Phil, thanks  I tried using the different input on the preamp, but same thing happened.

Brucek, I only noticed this issue when changing to revealing speakers and cables.

1ZIP, explained in greater detail what i have done..

Thanks to all!

[Mad Mr H]

Hi,

From your last post.......

Change the RCA lead from your pre to power amp - change the stereo pair to a different set.
Report results

IF both ok then was that cable, if still an issue then issue can only be power amp.

Could you describe "lifeless" is it just a lower level - you can adjust with balance to get the level the same if its level related (MONO audio to check this)

OR is it different audio response?

[jdandy]

JustAudio.......Since the problem moved to the right channel speaker when you swapped the premplifier output, but did not travel to the right channel when you swapped the CD player outputs, I would suspect a problem with the preamp or the interconnects between the preamp and the power amp.  New interconnects are not always trouble free.

[1ZIP]

Agree;

Left pre out to left pwr in
right pre out to right pwr in

Left side lifeless

Left pre out to right pwr in

Right side lifeless

Seems to rule out the pwr amp and points to left side out of the pre or the left pre out to right pwr in cable/connector

[rob80b]

Case 2: Changed RCA input on power amp from left out (on pre amp) into right in (on power amp):
Result: Right Speaker lifeless compared to left speaker

Thanks to all!

Agree;

Left pre out to left pwr in
right pre out to right pwr in

Left side lifeless

Left pre out to right pwr in

Right side lifeless

Seems to rule out the pwr amp and points to left side out of the pre or the left pre out to right pwr in cable/connector

Have to agree it's not the amp, just swap the the speaker cable connections at the amp to confirm. Sounds like a possible short in one of the interconnects from the preamp to the amp, it can happen with new cables.

Robert

[JustAudio]

Thanks to all for your feedback! Makes a newbie feel real welcomed.
When I say lifeless, I mean that it does not capture the inner harmony of the music as much... The sound signature is the 'same' but less....

I will try the recommendations as described and report back..

 

[Eric]

Boy am I glad my Drill Instructor is not here

[Elizabeth]

The new cable may have a 'cold solder' joint? Thus it works, but not perfectly.

[brucek]

Thanks to all for your feedback! Makes a newbie feel real welcomed.
When I say lifeless, I mean that it does not capture the inner harmony of the music as much... The sound signature is the 'same' but less....

I will try the recommendations as described and report back..

 

Yeah, take the cable that you feel works and use it on both right and left channels individually to ensure you're satisfied. Then take the cable in question and perform the same test and ensure you don't like the sound regardless of channel.

ltr