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Mike Coatham Mike Coatham is offline
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Default ESL57s - loss of high frequency?


"John Smith" wrote in message
...
[This reply got trapped in some e-mail limbo but has re-emerged so I'm
letting it be sent now in the hope someone remembers what were discussing]

Jim, Mike,

I bought the meter from Maplins about 3 years ago. I don't remember the

make
and I'm not at home to check. Maplins had it at £50 or £60 but claimed the
full price was around £100 and when I looked around the net it was on sale
elsewhere for around £100 so I guess it's accurate enough for my needs.

I set it up 12 inches from the centre of the speaker mounted on a camera
tripod (the meter has a tripod mount). Each speaker was measured

separately
so 4 runs of the test. I set the volume control as I would for normal
listening. The test CD (EMI) has a series of tracks playing a fixed
frequency for about 10 seconds (20Hz-20kHz). The volume coding is the same
for each track (15dBA below peak I think). For each frequency I noted the
meter reading (its a digital readout). While the TDL readings stayed about
the same from 8-15kHz the Quads dropped over 12dBA and by 20kHz they were
over 15 dBA less than the TDLs. I can't hear much above 10kHz these days

but
the meter had no problem and I knew what frequency was playing by the

track
number on the CD player.

Does this help or do you need the actual meter readings?

Thanks for the interest.

John.

"Jim Lesurf" wrote in message
...
In article , Mike Coatham

wrote:

"John Smith" wrote in message
...
Hi,

I compared my 1974 pair of ESL57s against a pair of newish TDL
speakers using a test CD with stepped tones and measured the output
with a sound level meter. The high-frequency roll-off of the ESL57s
was very noticable. The higher tones (10kHz up) were there but the
volume dropped off rapidly.

[snip]

Actually you may not have a problem with the ESL's per se but with the
listening position. The treble panels in the ESL 'beams' the sound to
one specific spot.


John: Could you tell us more about the microphone and speaker locations,
etc? Also could you give the details of what sound levels you measured

and
at what frequencies? My initial reaction is was the same as Mike's, but

it
would help us to diagnose/advise if we have more detailed/specific info.

Slainte,

Jim


Hi John,

Your meter was way too close to the Quads to get any meaningful ( accurate)
readings. Trouble here is you could be trying to fix something that isn't
broke by assuming the data you have collected is actually correct.
The Quad ESL, as I mentioned earlier certainly beams the HF content, so you
need to be far enough back to get accurate measurements. Unfortunately, I
have no idea what the original test parameters were for the ESL, but you
can bet your boots the measuring mic wasn't 12 inches from the centre .
What I suggest you do is set up the meter at your normal listing position,
and have someone tilt the ESL backwards and forwards whilst playing some HF
content. Note the meter change as the ELS is moved - and set them up at the
position where the HF content is at a peak. Then measure the whole spectrum
and see what results you get.