Possible issue with Classé?

[Birdy]

Need some help from the experts.
My system is 202-700-2200-802D
Due to my living place I’m quite restricted in the way I can position my system.

So speakers are 3.60m from each other, listening position is about the same distance.
There is chimney, 80 cm deep, between the speakers (yeah I know what the B&W brochure says about chimney…), situated from the centre of the line joining the speakers and extending towards the right speaker. Only 10 cm of the depth of the speakers are hidden by the chimney, the rest of the speakers are free of its influence ( or anyway I believe so…).

Moreover, the distance from the back of speakers to wall is not the same on both sides, it’s about 70 cm for the left speaker and 50 for the right one. Also the material for this wall is not the same..

My problem is this, most of the time when I listen to music I have this strong impression that the soundstage from center to right is a bit dead, or too prominent on the left side.
Understand me correctly when an instrument is mixed to appear in the right hand speaker I hear it loud and clear; it is everything that is between the centre and the right which is a bit shy.
My wife describes the same phenomena as instruments look closer on the left.

Made a measurement with a sound meter and in order to have the same level I have to put the balance around 1.0 on the right.
Initially I was thinking that some cds were badly mixed, not well balanced; but it makes no sense as it is always the same left side more present, never the right one.
When I put the balance around 2,5 on the right side, sound looks more balanced.
I remember reading something on this forum about someone who had a similar issue (soundstage stronger on the left) but I can’t retrieve it…. Also I’m not sure I have an issue or not, I mean for the electronic part.

So what do you think?
Acoustic problem, speaker problem, cable problem or electronic problem?
Any advise will be really welcomed, as lately I’m more zapping the songs and playing with the balance than enjoying music ….

Birdy

[sikoniko]

you can answer part of that quick... swap the interconnects so left becomes right and right becomes left and see what happens.

it is probably acoustics though.

[Rosso_Corsa]

Yes, as the above poster suggested, swap things over and re-check. I'm willing to bet it's acoustics. I have a similar problem in my room where I have lots of padding on one side and is quite bare on the other. Bare side sounds louder.

[Glen B]

I too have always had a problem where one channel occasionally sounds louder than the other, though it has been dependent on the music material. I have a partial wall to one side of the listening space and open space on the other. This phenomenon has always been present despite equipment changes.

[ChrisssB]

I also had the same feeling as you Birdy.
That the left speaker sounded louder than the right one. Also speaker positioning is not optimal in my room.
So even though everything was telling me its room acoustics I still wanted to be sure about it. So here’s what you can do to find out what’s happening (I did found that there was no issue with my electronics):
Take a mono recording; does this make the soundstage more centered?
Using that mono recording, use an SPL meter and measure the sound of each speaker unit (tremble, mid, bass). What I did was to hold the SPL meter VERY close (1 cm) to the unit I was measuring so room acoustics would be minimal. For a given piece of music (mono always) you’ll get a max reading. Compare maximum readings of the left speaker’s drive units with the max readings of the right speaker’s units. You’ll see (as I did) that they will be identical and you’ll rest your mind about your electronics.
Its not a scientific way but lacking the proper tools to do measurements like those stereophile does, you can still have a pretty good picture on what is really happening.
I hope that helps
Best regards Chris

[Birdy]

I also had the same feeling as you Birdy.
That the left speaker sounded louder than the right one. Also speaker positioning is not optimal in my room.
So even though everything was telling me its room acoustics I still wanted to be sure about it. So here’s what you can do to find out what’s happening (I did found that there was no issue with my electronics):
Take a mono recording; does this make the soundstage more centered?
Using that mono recording, use an SPL meter and measure the sound of each speaker unit (tremble, mid, bass). What I did was to hold the SPL meter VERY close (1 cm) to the unit I was measuring so room acoustics would be minimal. For a given piece of music (mono always) you’ll get a max reading. Compare maximum readings of the left speaker’s drive units with the max readings of the right speaker’s units. You’ll see (as I did) that they will be identical and you’ll rest your mind about your electronics.
Its not a scientific way but lacking the proper tools to do measurements like those stereophile does, you can still have a pretty good picture on what is really happening.
I hope that helps
Best regards Chris

Great idea!! :T :T

Also it sounds more scientific than swapping cables ( although I thank the author for the suggestion... that I had no time to try yet)

Just have to find a mono recording now...... :roll: :roll: :roll:

Birdy

[ChrisssB]

One more thing.......you'll be amazed on how good a mono recording will sound thru your system :-)

[Birdy]

So I tried 8O
Was less easy than I thought...
First I found a good old Bill Evans, with a track in mono and exactly the same track in stereo.

Listened to the stereo first then the mono; clearly a big diffrence, the mono seems slightly offset on the left, but I have to give it a second try to be sure.

The measurement part was not so simple as I thought as you should measure exactly the same portion of track to be correct; also the reading is changing all the time as it is not a simple sound :roll:

Anyway the readings are +/- the same on left and right for each driver.
So I'm a bit puzzled now, mono sound seems to come slightly left of center; but measurements seem to be the same on both sides....
What am I supposed to conclude from this? That my system is symetrical and I have an accoustic problem? Dunno... :roll: :roll: :roll:

How did you resolve your problem ChrisssB? or is it unresolved?

Birdy

[Eliav]

I used to experience the same issue ( image drifting to left, "dead spots" and lack of detail from the right hand speaker) with my system. Since the problem started after rearranging my listening room, I had realized room acoustic response had something to do with this. It appeared in my case that my 802d were towed in too much, When I towed them out to a near parallel position, the sweet spot got back to life with a razor sharp central "spot light" and a great symmetrical field depth.
It took me a while to realize it was acoustics. it was easy to blame my system components;For a while, I too was suspecting my cp700 for not being balanced,especially after RebeMan described the problem he had had with his cp700. I also thought for a while that something was wrong with my CAM 400 monos.Like said, It ended up not being the case at all.
IMHO, since Classe and B&W are such reliable high end products, it is generally unlikely to be the cause of issues such as this, rather, room acoustics is a much more common cause.
Regards
Eliav

[RebelMan]

I too have always had a problem where one channel occasionally sounds louder than the other, though it has been dependent on the music material. I have a partial wall to one side of the listening space and open space on the other. This phenomenon has always been present despite equipment changes.

Which side was louder wall side or sans wall side?

[RebelMan]

Birdy, as other posters have already mentioned there is a high probability that room acoustics are producing the phenomena you observed. Hard surfaces like nearby walls can kill frequencies occurring below 1 kHz. This reduction in acoustic energy can produce a sonic imbalance or a lightening of the load on once side (or boost in some cases where soft materials exist).

Like Glen I have a wall on onside but not the other and it is this side where some weight to the presentation is lost. To compensate the right channel I boost balance by 1.0db. The balance feature wasn't intended to compensate for room acoustics like this but it can provide some temporary relief from room inadequacies.

All speakers have some level of imbalance to them but B&W goes to great lengths to ensure theirs are balanced and sonically matched. Classe' does likewise with the equipment they manufacture too. If you have a genuine problem with your gear you'll know it.

What Birdy is describing sounds like some minor speaker placement issues coupled with room/obstacle interferences. Some great advice has already been given, like switching cables and testing with mono recordings. I will add that a good test disc with sinusoidal test tones should also be employed and metered for each speaker (at the same close distance) to minimize room interactions. Then I suggest (temporarily) moving the speakers out as far into the room and free from most objects as possible. Follow on by playing a favorite tune, a tune that you are most familiar, and perform near field examination.

It will take some effort to setup but in the end you'll know for sure whether it’s your room, mind tricks or perhaps a little bit of both at work.

[Glen B]

Which side was louder wall side or sans wall side?

The wall side was louder.

[ChrisssB]

So I tried 8O
Was less easy than I thought...
First I found a good old Bill Evans, with a track in mono and exactly the same track in stereo.

Listened to the stereo first then the mono; clearly a big diffrence, the mono seems slightly offset on the left, but I have to give it a second try to be sure.

The measurement part was not so simple as I thought as you should measure exactly the same portion of track to be correct; also the reading is changing all the time as it is not a simple sound :roll:

Anyway the readings are +/- the same on left and right for each driver.
So I'm a bit puzzled now, mono sound seems to come slightly left of center; but measurements seem to be the same on both sides....
What am I supposed to conclude from this? That my system is symetrical and I have an accoustic problem? Dunno... :roll: :roll: :roll:

How did you resolve your problem ChrisssB? or is it unresolved?

Birdy

Keep the process as simple as possible. By this I mean that you don’t have to see if the SPL reading is the same at lets say 0.46 secs (song time) on the left and right speaker. This would be difficult to do. What I did was to let song playing for 2 minutes. The SPL meter reading all that time (2 mins) keep changing, but what I do keep from all these readings is the maximum one. Then I do the same with the other speaker using the same 2 minutes from the same song. I get a maximum reading once again. I then compare those maxima.
But at the end of the story as you’ve already seen the readings are the same, so that means that there’s no problem with your electronics or your speakers. You should not forget that if we talk about cars, high end is the equivalent of F1 not a neighborhood car race. By this I mean that the system is so good that for one (as yourself) to get the best results is to try to eliminate faults that have to do more with the “environment” (rack, isolation, electric filtering, room acoustics etc.) than with the system itself .
Room acoustics can do nasty tricks which are more obvious when a system is of higher quality (as yours). You must be sure that your system will sound very different in another room while itself will be always the same
In my case, on the left side there are more reflective surfaces (heavy polished large furniture, mirror etc) than on the right side.

Best regards Chris

[Birdy]

I used to experience the same issue ( image drifting to left, "dead spots" and lack of detail from the right hand speaker) with my system. Since the problem started after rearranging my listening room, I had realized room acoustic response had something to do with this. It appeared in my case that my 802d were towed in too much, When I towed them out to a near parallel position, the sweet spot got back to life with a razor sharp central "spot light" and a great symmetrical field depth.
It took me a while to realize it was acoustics. it was easy to blame my system components;For a while, I too was suspecting my cp700 for not being balanced,especially after RebeMan described the problem he had had with his cp700. I also thought for a while that something was wrong with my CAM 400 monos.Like said, It ended up not being the case at all.
IMHO, since Classe and B&W are such reliable high end products, it is generally unlikely to be the cause of issues such as this, rather, room acoustics is a much more common cause.
Regards
Eliav

Tks for sharing your experience Eliav. :T

Funny that all people that encountered this problem had it with a proeminent left side.

Never tried to place your speakers asymmetrically, in depth, wideness or toe in? :roll:
Or is it a crime?

Birdy

[Birdy]

Birdy, as other posters have already mentioned there is a high probability that room acoustics are producing the phenomena you observed. Hard surfaces like nearby walls can kill frequencies occurring below 1 kHz. This reduction in acoustic energy can produce a sonic imbalance or a lightening of the load on once side (or boost in some cases where soft materials exist).

Like Glen I have a wall on onside but not the other and it is this side where some weight to the presentation is lost. To compensate the right channel I boost balance by 1.0db. The balance feature wasn't intended to compensate for room acoustics like this but it can provide some temporary relief from room inadequacies.

All speakers have some level of imbalance to them but B&W goes to great lengths to ensure theirs are balanced and sonically matched. Classe' does likewise with the equipment they manufacture too. If you have a genuine problem with your gear you'll know it.

What Birdy is describing sounds like some minor speaker placement issues coupled with room/obstacle interferences. Some great advice has already been given, like switching cables and testing with mono recordings. I will add that a good test disc with sinusoidal test tones should also be employed and metered for each speaker (at the same close distance) to minimize room interactions. Then I suggest (temporarily) moving the speakers out as far into the room and free from most objects as possible. Follow on by playing a favorite tune, a tune that you are most familiar, and perform near field examination.

It will take some effort to setup but in the end you'll know for sure whether it’s your room, mind tricks or perhaps a little bit of both at work.

Rebel, thanks for your sound advise.

I'm quite new at this game I must confess.
I mean I always listened with great pleasure to music since many years but it is only recently that I discovered that it was possible to achieve such a high level of performance ( and anyway it's also only recently that my wallet and my crazyness authorized me to start auditioning that kind of material... )
So I jumped immidiately from a quite basic system to an high end one with no intermediate steps.... ops:

Also as I said above my room is quite complicated and not dedicated to music only.
i had to place the speakers on the "wrong length" of the room, there is this chimney, the back wall not at the same distance, side walls not equidistant, also there is hole in my ceiling starting from mid left-center till just overhead the right speaker, bright room with no carpets for waf,very light curtains again for same waf, a big sofa in front and close to right speaker, a supportive column for the ceiling just on the right side and a bit in front of the listening position and to complete everything a big stair also on the right side of piece in front of right speaker.... :M :M :M

The only good news is that it's a renting and we hope to buy something in a not too far future... :

Anyway in the mean time I would like to optimize what I have....

So I'm still discovering all this high performance system and I would like to understand clearly a few things you said.

I will add that a good test disc with sinusoidal test tones
Where in hell can I find such a disc???? :E :E :E

Then I suggest (temporarily) moving the speakers out as far into the room
Isn't it more easy to simply advance the listening position instead of try to move those heavy speakers ( even if they have rollers... :lol: ) or the result to be achieved wouldn't be the same?


and perform near field examination.

You sound like a doctor to me...
Seriously, this is a term encountered a lot of times that I still don't understand very well... ops:

Tks for your help,

Birdy

[Birdy]

Keep the process as simple as possible. By this I mean that you don’t have to see if the SPL reading is the same at lets say 0.46 secs (song time) on the left and right speaker. This would be difficult to do. What I did was to let song playing for 2 minutes. The SPL meter reading all that time (2 mins) keep changing, but what I do keep from all these readings is the maximum one. Then I do the same with the other speaker using the same 2 minutes from the same song. I get a maximum reading once again. I then compare those maxima.
But at the end of the story as you’ve already seen the readings are the same, so that means that there’s no problem with your electronics or your speakers. You should not forget that if we talk about cars, high end is the equivalent of F1 not a neighborhood car race. By this I mean that the system is so good that for one (as yourself) to get the best results is to try to eliminate faults that have to do more with the “environment” (rack, isolation, electric filtering, room acoustics etc.) than with the system itself .
Room acoustics can do nasty tricks which are more obvious when a system is of higher quality (as yours). You must be sure that your system will sound very different in another room while itself will be always the same
In my case, on the left side there are more reflective surfaces (heavy polished large furniture, mirror etc) than on the right side.

Best regards Chris

I will try your method for my second measurement.

Kalimera!

Birdy

[RebelMan]

So I'm still discovering all this high performance system and I would like to understand clearly a few things you said.

I will add that a good test disc with sinusoidal test tones
Where in hell can I find such a disc???? :E :E :E

You can find test discs at stereophile and Chesky Records but sites like testaudio.com have more flexible options.

Then I suggest (temporarily) moving the speakers out as far into the room
Isn't it more easy to simply advance the listening position instead of try to move those heavy speakers ( even if they have rollers... :lol: ) or the result to be achieved wouldn't be the same?

Not in your case. Your setup is asymmetrical and you have objects in between. You would need to clear a path for the sound waves to travel.

and perform near field examination.

You sound like a doctor to me...
Seriously, this is a term encountered a lot of times that I still don't understand very well... ops:

LOL, not trying to be but I’ll take that as a compliment. “Near Field” is a poor man’s version, rather attempt, to reproduce an anechoic chamber response from your speakers. In other words, to coerce the actual response of the speakers in your listening space while simultaneously minimizing the room’s influences. You situate your listening position as close as possible, usually within 1 meter. Then you study the acoustic behavior of the drivers individually overlooking sound-staging and imaging accuracy.