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Graham Audio LS5/9

Comparing the top pair of curves to the bottom pair of curves, I don't see much difference between 2kHz-7kHz. Perhaps you're confusing the left and right channels of each measurement?

For clarity, the top two traces show the right hand LS6 and LS5/9. The bottom two traces show the left hand LS6 and LS5/9.
 
could be this (in the midrange) the "BBC dip" mentioned before who the 5/9 would have?

A BBC dip would be a couple of dB around the 2-3 kHz region. From what I’ve seen, modern BBC Heritage designs don’t have this dip. It would be easy enough to add a dip with eq if you want.

Edit: To be clear there are two separate effects here:
a. A dip in the on axis FR. Modern BBC heritage speakers don’t seem to have this dip. It can be added by eq, if one wants.
b. A dip in the *power response* due to the increasing directivity of the, typically, 20 cm woofer crossing over around 3kHz. This is intrinsic to BBC designs and cannot be emulated by DSP.

Current mainstream speakers aim for more constant directivity.
 
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No. Look again at the differences in 2.5 -7 kHz region. The LS 6 clearly has the flatter FR. The difference will be audible.

The larger drivers may well have lower distortion, but audibility of speaker distortion, if not too high, is a matter of some debate. Certainly, FR and directivity are more important. IOW, somewhat lower distortion is unlikely to affect preferences in the same way as FR.

I agree that the LS6 will probably have less directivity issues due to the smaller midwoofer, but that is not aparent in these measurements.
I don't really see it as flatter trend except for the region above 3kHz where it's less bumpy. This is a single point in-room measurement and with a bit more smoothing the two speakers' response won't be that much different.


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A BBC dip would be a couple of dB around the 2-3 kHz region. From what I’ve seen, modern BBC Heritage designs don’t have this dip. It would be easy enough to add a dip with eq if you want.

Edit: To be clear there are two separate effects here:
a. A dip in the on axis FR. BBC heritage speakers don’t seem to ha ve this dip. It can be added by eq, if one wants.
b. A dip in the *power response* due to the increasing directivity of the, typically, 20 cm woofer crossing over around 3kHz. This is intrinsic to BBC designs and cannot be emulated by DSP.

Current mainstream speakers aim for more constant directivity.

I've got measuremens of most BBC and BBC-inspired speakers and the only models with an obvious presence dip on-axis are the Spendor SA3 and the Harbeth HL.
Most other models will show a dip off-axis but that may or may not reflect on the response at the listening spot depend on the room width and whether the side walls are treated or not.
 
I agree that the LS6 will probably have less directivity issues due to the smaller midwoofer, but that is not aparent in these measurements.
I don't really see it as flatter trend except for the region above 3kHz where it's less bumpy. This is a single point in-room measurement and with a bit more smoothing the two speakers' response won't be that much different.


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Less bumpy = flatter. A 3dB peak at 4 kHz, where the ear is highly sensitive is not trivial. This is in-room, not quasi-anechoic, so indicative of what the listener would percieve.
 
I've got measuremens of most BBC and BBC-inspired speakers and the only models with an obvious presence dip on-axis are the Spendor SA3 and the Harbeth HL.
Most other models will show a dip off-axis but that may or may not reflect on the response at the listening spot depend on the room width and whether the side walls are treated or not.

As I've said, modern BBC heritage speakers, unlike say, a BC-1, don't have this dip, so we agree.

Power response certainly affects timbre. This is not the same as FR.
 
Less bumpy = flatter. A 3dB peak at 4 kHz, where the ear is highly sensitive is not trivial. This is in-room, not quasi-anechoic, so indicative of what the listener would percieve.

It is in room, so it also includes reflections. It is also representative of a single point in space; move the mic 10mm in each direction and the response will change.
I don't see a peak at 4kHz but a broad (low-Q) hump.
The LS6 treble is shelved down by 3dB.

But these are in-room measurements, not ideal for detailed comparisons.
 
As I've said, modern BBC heritage speakers, unlike say, a BC-1, don't have this dip, so we agree.

Power response certainly affects timbre. This is not the same as FR.

Power response is 360º frequency response.
 
I don’t normally fill this particular model, but they can be supplied with holes for filling.

I used the same model with Spendor speakers many years ago, but I had to fill them otherwise they resonate producing bad effects on sound
I filled more ore less 70% of the capacity
 
I used the same model with Spendor speakers many years ago, but I had to fill them otherwise they resonate producing bad effects on sound
I filled more ore less 70% of the capacity
Surprised you needed to fill them. From all the older photos of bbc design speakers e.g. spendor bc1 they all seem to be on open frame metal stands.

I recently bought Harbeth shl5+ and debating whether to go with metal (same custom design ones strictly stereo mentioned) or wooden designs.
 
I have GA 5/9, initially I used them with their original open frame stands. Later I found some rare Foundation Designer stand for Rogers 5/9, they sound better in all the parameters compared to the original stands.

I would not use not filled stands, they simply resonate.

The open fram stands are different, they cannot be filled....but they don't resonate or resonate less than the customsdesign stands
 
Thread crap incoming, but has anyone heard the latest Rogers LS5/9?

The whathifi Australia suite of measurements look ok, the hifiworld not so much. Varying reports anecdotally, good mag reviews FWIW. Assuredly the most expensive LS5/9 type in production.
 
I have GA 5/9, initially I used them with their original open frame stands. Later I found some rare Foundation Designer stand for Rogers 5/9, they sound better in all the parameters compared to the original stands.

I would not use not filled stands, they simply resonate.

The open fram stands are different, they cannot be filled....but they don't resonate or resonate less than the customsdesign stands
Do you think wood would be best? Currently have on wooden ikea stools and sound very good.
 
It is in room, so it also includes reflections. It is also representative of a single point in space; move the mic 10mm in each direction and the response will change.
I don't see a peak at 4kHz but a broad (low-Q) hump.
The LS6 treble is shelved down by 3dB.

But these are in-room measurements, not ideal for detailed comparisons.


My comment was limited to the differences in the curves *as presented*. Whether these are due to room effects, voicing, etc. is a separate discussion. The 3 dB between the two, call it a peak, hump, convex feature, whatever, it’s there and will be audible. The LS6 is flatter in the region under discussion, again, my comment was limited in scope to the 2.5-7 k region.

Note that I am not judging the audible or technical merits of either speaker based on these curves, only commenting on what looked like interesting differences.

Power response is 360º frequency response.

That is not correct.
 


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