Klipsch RP8000-f output volume different between the two speakers

Faiek P

Novice Member
Hi everyone,

I have just purchased a new pair of Klipsch RP8000-f speakers and running them off a new Cambridge AXR100 amp. I am noticing a slight difference in the output (bass, mids & highs) between the two speakers. Its not very noticable when playing them at zero balance but when I use some of the speaker stereo (left,right) tests available online I could clearly tell the one was louder than the other.

I have tried changing the amp and tested on my old Denon avr;
I have tried changing the speaker cables;
I have double checked the speaker binding posts for contact and tightness, and checked polarities;
I have used different input sources;
I have also swapped the location of the two speakers;
I have also got a second person to listen with me and they heard the same

There is no issue with the quality of the sound itself, its just a lower volume. Has anyone had a similar issue like this with Klipsch or should I just be contacting the store. I feel I have exhausted all testing options.
 

Ugg10

Distinguished Member
Have you tried a second set of speaker to rule out the amp having a bias in its balance circuit ? Also you can use a free phone SPL app and pink noise track on spotify to measure the output (same distance from each speaker with the other disconnected). Finally depending on your room the speaker/room interaction may be providing a boost or a null on each speaker giving different volumes from each speaker. Have you tried moving the speakers within the room or better still moving them into another room to see if the difference persists.
 

Faiek P

Novice Member
Have you tried a second set of speaker to rule out the amp having a bias in its balance circuit ?
I did not as I don't have another set of speakers. I did try the speakers on my Denon avr and I am noticing the same problem there. Also swapped the speaker channel cables left to right and vice versa but its the same one thats having the lower volume.
 

Ugg10

Distinguished Member
If you didn't change the position of the speaker it could still be Room/Speaker interaction ahich can be as much as 10db for big bass and mid bass nulls.
 

Faiek P

Novice Member
If you didn't change the position of the speaker it could still be Room/Speaker interaction ahich can be as much as 10db for big bass and mid bass nulls.
That was also my first thought so I swapped the location of the speakers and the one with the lower volume was the same even in the new location. New speakers & new amp really shouldn't be giving me so many headaches lol
 

Ugg10

Distinguished Member
In terms of location I mean moving the speaker a foot or so to the left/right, forward/back. Even if the new position is not practical then it will at least show you if it is the speaker or the position of the speaker in the room.
 

Faiek P

Novice Member
In terms of location I mean moving the speaker a foot or so to the left/right, forward/back. Even if the new position is not practical then it will at least show you if it is the speaker or the position of the speaker in the room.
Thanks for the troubleshooting help Ugg10. I've just tried that now and moved them both about a metre and a half forward but no improvement. I've had a good listen again and the most noticable loss is in the low bass. Not sure if this helps pinpoint anything
 

Ugg10

Distinguished Member
Does sound like a faulty speaker, the only other thought is that if they are brand new speakers can take up to 100hrs to reach a stable sound due to loosening/bedding of the mechanical and rubber parts. If you are past this point it’s probably time to contact the dealer for a replacement or return.
 

Ugg10

Distinguished Member
The other obvious thing, and we have all been there, it so make fully sure that the speaker cables are connected red to red and black to black with the amp. And if they are biwirable that you have the jumper in tightly if single wiring.
 

Faiek P

Novice Member
The other obvious thing, and we have all been there, it so make fully sure that the speaker cables are connected red to red and black to black with the amp. And if they are biwirable that you have the jumper in tightly if single wiring.
Yeah I've wired and rewired, triple checked polaries, twice now. I have one more thing I'm going to try. Will remove the bi wire jumper and test the upper and lower post separately. Could give me a better indication of exactly where the loss is once separated. Will update once I have some joy. Thanks Ugg10
 

password1

Distinguished Member
Every single Cambridge Audio amp I've owned has right bias at low volume.

Have you tried swapping the left and right speakers and tried swapping the left and right from the source (simply swapping the left and right phono on the back of the amp or source would be easier)

If the speakers are made together and tested at the factory then I can't imagine why one would be louder than the other, other than poor quality control and one or both of your speakers slipped through the inspection/quality checks.
 

Faiek P

Novice Member
Every single Cambridge Audio amp I've owned has right bias at low volume.

Have you tried swapping the left and right speakers and tried swapping the left and right from the source (simply swapping the left and right phono on the back of the amp or source would be easier)

If the speakers are made together and tested at the factory then I can't imagine why one would be louder than the other, other than poor quality control and one or both of your speakers slipped through the inspection/quality checks.
At low volume yes I can understand this could be the case. Tried all as you mentioned. I also downloaded one of these db meters from the App Store, yes I know it’s not very precise but at least it gives me an indication and validates my ears lol. When playing at around 60db volume I am seeing a 2-3db difference from left to right. I suspect I have one of the lemons
 

password1

Distinguished Member
I would let the dealer you bought them.off know and see what they suggest.. hopefully swap for another pair or at least test against another pair.

The only other thing i can suggest is to test each speaker's db level separately on the sane channel and adjust the balance on the amp fully to that channel.
 

Faiek P

Novice Member
I would let the dealer you bought them.off know and see what they suggest.. hopefully swap for another pair or at least test against another pair.

The only other thing i can suggest is to test each speaker's db level separately on the sane channel and adjust the balance on the amp fully to that channel.
I will get an actual sound meter today from a friend and try this out. Thanks
 

Faiek P

Novice Member
Just did a test using a sound meter now; used same one channel; same 20 seconds of a song; same volume; speakers side by side; sound meter on a tripod in the centre of the speakers; results was around 4db difference between the two speakers. Wish I could add the video I made of it but here's a screenshot showing highest db of each test. Guess its time to contact the dealer

Screenshot 2021-06-18 at 16.51.12.png
Screenshot 2021-06-18 at 16.51.59.png
 

password1

Distinguished Member
If everything is the same and one speaker is louder than the other then there is definitely something wrong with the speakers.. contact the dealer and see what they suggest.. hopefully swap for a different pair.
 

3rdignis

Active Member
Test your hearing with a free app on your phone and earphones.
 

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