PSB Image B6 review from Stereophile

[3db]

Another good review..

http://stereophile.com/standloudspeakers/psb_image_b6_loudspeaker/index1.html

 

[echoesian]

Would B6 overwhelm for surround use?

 

[GO-NAD!]

Would B6 overwhelm for surround use?

No, it won't overwhelm. But, all you would probably gain over the B4/B5 is bass frequency extension. Used as surrounds and crossed over at around 80Hz, that deeper extension would go to waste.

 

[jostenmeat]

No, it won't overwhelm. But, all you would probably gain over the B4/B5 is bass frequency extension. Used as surrounds and crossed over at around 80Hz, that deeper extension would go to waste.

My impressions have generally not been in accordance with this statement. As the saying goes, "crossovers are not brick walls". I like the extension that larger speakers can give with surrounds. To me, the difference can be rather obvious. I don't know if we can't really localize below 80hz, but even if that was utterly true, I might guess that just the midbass itself can be much improved.

That said, the biggest compromise, IMO, is with the aesthetics of larger surrounds.

If you ask someone like TLS Guy, depending on the format in question, he might be much more assertive with the need for bass/midbass capable surrounds.

If you have a guitar in the house, and it is in tune, the lowest string is a hair above 80hz, I think it may be about 82.5 when using perfect intervals from "A". Give it a slight tug, and then it's probably 80hz. Have your wife pluck it from anywhere in the room, and yeah the attack/harmonics will make it all the more localizable, but you might think more similarly to me after the experiment. I dunno.

FWIW, I have terrible extension for a bass singer, but I can almost hit 80hz. Many singers can go below 80hz. And just to beat the dead horse, crossovers are not brick walls. IOW, if the singer was a speaker instead, all of a sudden you may very well hear even lower frequencies (in the reproduction sense).

 

[AJinFLA]

My impressions have generally not been in accordance with this statement. As the saying goes, "crossovers are not brick walls". I like the extension that larger speakers can give with surrounds. To me, the difference can be rather obvious.

There are good reasons for this. First, by adding more LF sources, you are spatially averaging the summed responses at your seated position, which tends to smoothen the Frequency response (the multi-sub concept). Secondly, it is likely possible that you are going to be closer to one of those rear CH LF sources. The closer you are to that monopole LF source, the less effect modes will have on the response, you are essentially in the "near field" of the source, further smoothening the perceived LF response.

I don't know if we can't really localize below 80hz, but even if that was utterly true, I might guess that just the midbass itself can be much improved.

We can't per se....but that's doesn't mean we can't hear/localize a LF source (sub) crossed, even steeply/brickwall filtered, at 80hz .
The reason is that when driven hard, the motor of the driver itself, can generate IM products, subharmonics well above 80hz, into the localizable frequency range. The filter (XO) has absolutely no effect on this, because it is occurring after the filter.

That said, the biggest compromise, IMO, is with the aesthetics of larger surrounds.

Bingo .
Not just surrounds. Aesthetics (which also includes placement) is the number one seller of all things speakers (etc.). SQ is usually off in the distance somewhere, even if most would be loathsome to admit it, or blissfully ignorant of it .

cheers,

AJ

 

[GO-NAD!]

My impressions have generally not been in accordance with this statement. As the saying goes, "crossovers are not brick walls". I like the extension that larger speakers can give with surrounds. To me, the difference can be rather obvious. I don't know if we can't really localize below 80hz, but even if that was utterly true, I might guess that just the midbass itself can be much improved.

That said, the biggest compromise, IMO, is with the aesthetics of larger surrounds.

If you ask someone like TLS Guy, depending on the format in question, he might be much more assertive with the need for bass/midbass capable surrounds.

I wasn't trying to give the impression that a crossover is a brick wall. Are you saying that the LF response of the B4/B5 hits a brick wall at 80Hz? I would surmise that the B5, at least, will have sufficient extension below 80 Hz to do the job adequately. The B4 could be debatable.

I stand by my view that little, if any benefit would derived from the B6 in the surround mode.

 

[jostenmeat]

I wasn't trying to give the impression that a crossover is a brick wall. Are you saying that the LF response of the B4/B5 hits a brick wall at 80Hz?

Of course not!! Sheesh.

I would surmise that the B5, at least, will have sufficient extension below 80 Hz to do the job adequately. The B4 could be debatable.

I've used three different PSB speakers for surrounds in the last two years, two of which are from the previous Image generation. The extension is rather obvious, as I previously stated, with larger bookshelves. In fact, and I've said this many times already just at this forum, that if I did it all over again, I would have drilled right into the (largest) B25s because in fact I do miss the extension. PSB since has given me instructions on how to do so, if I ever go back to those. It is noticeable even with 80hz xover. If my present rears and sides were capable of lower extension, I would in fact love to try a lower xover since my larger than life Danley DTS10 subwoofer is on the backwall (where my sub was previously on the sidewall), and that while it is known to have a strong resonant peak at around 54hz that must be EQd . . . I'd love to experiment more with xover settings . . . but enough of my story . . .

I stand by my view that little, if any benefit would derived from the B6 in the surround mode.

Little is indeed subjective. If you said it like that the first time, I might have been a bit less likely to respond. What I did respond to earlier was this: "Used as surrounds and crossed over at around 80Hz, that deeper extension would go to waste." That is what I disagree with.

(Honest question for anyone to answer): Why is it that some people recommend setting the xover at a full octave above the F3? Is it because real world material will simply exceed the 1w/2.83v, often at a distance beyond 1m? Perhaps for either headroom at the midbass, or to make sure mechanical limits are never tortured? Is it that because the stated specs are so exaggerated?

As of now I have S50 bipoles on the sides, and Alpha B1s for the rears, ceiling mounted. PSB states F3 at 65hz for the Alphas. Audyssey finds that instead to be at 90hz, and in so doing, will not even try to EQ below that point. Like the B5, it uses a 5.25" driver, with cabinet size being pretty similar.

If the aesthetics are totally fine with the OP, I heartily vote for the B6, assuming that it is the B5/B4s equal, outside of the increased extension (and/or power handling).

 

[TLS Guy]

Of course not!! Sheesh.



I've used three different PSB speakers for surrounds in the last two years, two of which are from the previous Image generation. The extension is rather obvious, as I previously stated, with larger bookshelves. In fact, and I've said this many times already just at this forum, that if I did it all over again, I would have drilled right into the (largest) B25s because in fact I do miss the extension. PSB since has given me instructions on how to do so, if I ever go back to those. It is noticeable even with 80hz xover. If my present rears and sides were capable of lower extension, I would in fact love to try a lower xover since my larger than life Danley DTS10 subwoofer is on the backwall (where my sub was previously on the sidewall), and that while it is known to have a strong resonant peak at around 54hz that must be EQd . . . I'd love to experiment more with xover settings . . . but enough of my story . . .



Little is indeed subjective. If you said it like that the first time, I might have been a bit less likely to respond. What I did respond to earlier was this: "Used as surrounds and crossed over at around 80Hz, that deeper extension would go to waste." That is what I disagree with.

(Honest question for anyone to answer): Why is it that some people recommend setting the xover at a full octave above the F3? Is it because real world material will simply exceed the 1w/2.83v, often at a distance beyond 1m? Perhaps for either headroom at the midbass, or to make sure mechanical limits are never tortured? Is it that because the stated specs are so exaggerated?

As of now I have S50 bipoles on the sides, and Alpha B1s for the rears, ceiling mounted. PSB states F3 at 65hz for the Alphas. Audyssey finds that instead to be at 90hz, and in so doing, will not even try to EQ below that point. Like the B5, it uses a 5.25" driver, with cabinet size being pretty similar.

If the aesthetics are totally fine with the OP, I heartily vote for the B6, assuming that it is the B5/B4s equal, outside of the increased extension (and/or power handling).

I think most people recommend setting the crossover at X2 F3 to protect the woofer, in ported enclosures.

The high pass filter is usually in a receiver is generally second order and the low pass fourth order. So if you set the crossover at X 2 F3, then the small woofer is electrically 12 db down at F3 at the point where it off loads from the enclosure.

Also the combination of second order high pass and fourth order low pass is likely to result in the best splice at X 2 F3. Also bear in mind when set up this way roll off will be 12 db per octave on the high pass from the crossover point to just above F3 and then it will become sixth order. So it is small wonder it is difficult to get it ideal

Now for sealed enclosures the driver does not offload and rolls off 12 db per octave acoustically at a higher point than a vented enclosure would.

So if you set your crossover at F3 then the high pass will be fourth order adding the acoustic and electrical slopes, and the fourth order receiver low pass filter will make a good splice.

So for AV ported speakers should ideally have an F3 no higher than 40 Hz and sealed enclosures between 60 and 80 Hz.

So when setting a crossover at 80 Hz extension to 40 Hz on all speakers is actually required for optimal results.

It all comes down to least of evils. Small drivers ported are cheaper and you can get F3 low enough to make the crossover in a satisfactory range.

To get sealed enclosures to have an F3 in the right range requires more expensive drivers and sensitivity will be lower.

I can attest to the fact that results improve the more capable all the speakers are.

 

[GO-NAD!]

Of course not!! Sheesh.

I knew you weren't trying to say that. I just wanted to make a point. If I (or anyone else for that matter) makes a statement that might be open to misinterpretation, I'd appreciate a chance to clarify, rather than have assumptions made about my underlying thought process.

For what it is worth, and looking at it in retrospect, my statement was ambiguous and I apologize for that.

Little is indeed subjective.

Yes, it is. I suppose it all depends on how far one is willing to strive in order to wring the best sound from his system.

So when setting a crossover at 80 Hz extension to 40 Hz on all speakers is actually required for optimal results.

So, I guess it'll have to be towers all around, eh?