Quad ESL2805 [was: And so...]
 

In article , Serge Auckland
wrote:

"Jim Lesurf" wrote in message
...

Question is: What decent, flexible, high quality adjustment boxes
are there that would let me do what I want? I don't want one of the
multiband 'graphic equalisers' as they may well do more harm than
good!

Jim, the Behringer DEQ2496 may do what you need. I use one with my
Meridian 'speakers to EQ the last few dBs of error in the frequency
response above 200Hz. They have both analogue and digital I/O and
decent true-peak (I think) metering. It also has a measuring microphone
input if one wants to do Real-Time frequency analysis. A great box for
around £220.

Thanks. That looks very interesting. I'll have a read though the manual. It
also makes me think that it may be used between the digitial sources and
the actual dac. A quick glance at the manual makes me think it will follow
the input sample rate for spdif. Does that then always follow at output as
well, or can that be left at 24/96 as per its internal computations?

Is there a particular dealer you'd recommend? I may try contacting the
makers anyway for info/advice.

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

Quad ESL2805 [was: And so...]
 

In message , Jim Lesurf
writes
In article , Serge Auckland
wrote:

"Jim Lesurf" wrote in message
...

Question is: What decent, flexible, high quality adjustment boxes
are there that would let me do what I want? I don't want one of the
multiband 'graphic equalisers' as they may well do more harm than
good!

Jim, the Behringer DEQ2496 may do what you need. I use one with my
Meridian 'speakers to EQ the last few dBs of error in the frequency
response above 200Hz. They have both analogue and digital I/O and
decent true-peak (I think) metering. It also has a measuring microphone
input if one wants to do Real-Time frequency analysis. A great box for
around £220.

Thanks. That looks very interesting. I'll have a read though the manual. It
also makes me think that it may be used between the digitial sources and
the actual dac. A quick glance at the manual makes me think it will follow
the input sample rate for spdif. Does that then always follow at output as
well, or can that be left at 24/96 as per its internal computations?

Is there a particular dealer you'd recommend? I may try contacting the
makers anyway for info/advice.

Slainte,

Jim

The DEQ2496 does offer a lot for the money and is a well known unit.

I would be wary of the SNR at the outputs though. My hearing is not at
all good any more, but the noise level when using one of these at low
output levels is not really adequate. The solution is to follow the
unit with a multi-channel analogue gain control (rather than using the
internal digital gain control), so that the crossover is working at a
high internal signal level.

Four-way log pots are easily available, but for more ways you might have
to have a look at some of the kits that use Analog Devices digital pot
chips. I can vouch for the quality of these chips, as I use them in my
PA and VA amplifier designs for my employer.
--
Chris Morriss

Quad ESL2805 [was: And so...]
 

In article ,
Chris Morriss wrote:
The DEQ2496 does offer a lot for the money and is a well known unit.

I would be wary of the SNR at the outputs though. My hearing is not at
all good any more, but the noise level when using one of these at low
output levels is not really adequate. The solution is to follow the
unit with a multi-channel analogue gain control (rather than using the
internal digital gain control), so that the crossover is working at a
high internal signal level.

Sounds like my view of most things Behringer. Good value, but more home
studio than professional.

--
*How can I miss you if you won't go away?

Dave Plowman London SW
To e-mail, change noise into sound.

Quad ESL2805 [was: And so...]
 

"Jim Lesurf" wrote in message
...
In article , Serge Auckland
wrote:

"Jim Lesurf" wrote in message
...

Question is: What decent, flexible, high quality adjustment boxes
are there that would let me do what I want? I don't want one of the
multiband 'graphic equalisers' as they may well do more harm than
good!

Jim, the Behringer DEQ2496 may do what you need. I use one with my
Meridian 'speakers to EQ the last few dBs of error in the frequency
response above 200Hz. They have both analogue and digital I/O and
decent true-peak (I think) metering. It also has a measuring microphone
input if one wants to do Real-Time frequency analysis. A great box for
around £220.

Thanks. That looks very interesting. I'll have a read though the manual.
It
also makes me think that it may be used between the digitial sources and
the actual dac. A quick glance at the manual makes me think it will follow
the input sample rate for spdif. Does that then always follow at output as
well, or can that be left at 24/96 as per its internal computations?

Is there a particular dealer you'd recommend? I may try contacting the
makers anyway for info/advice.

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics
http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

The output sample rate follows the input rate, at least mine does! If one's
using the analogue inputs, then the output rate can be set to whatever one
wants. It won't act as a sample-rate converter, for example taking in 44.1
and outputting 96k. As to dealers, I've bought from Dolphin Music, Digital
Village and GAK successfully with no problems. I use mine at the input of
my Meridian DSP 'speakers, effectively at the input of the DAC.

In an analogue system, it could be used as the DAC, as the digital and
analogue outputs are effectively in parallel, carrying the same signal.
Whether this would be considered good enough quality I won't make any
comment. I've not had a problem.

S.

Quad ESL2805 [was: And so...]
 

In article , Chris Morriss
wrote:
In message , Jim Lesurf
writes

Is there a particular dealer you'd recommend? I may try contacting the
makers anyway for info/advice.


The DEQ2496 does offer a lot for the money and is a well known unit.

I would be wary of the SNR at the outputs though. My hearing is not at
all good any more, but the noise level when using one of these at low
output levels is not really adequate. The solution is to follow the
unit with a multi-channel analogue gain control (rather than using the
internal digital gain control), so that the crossover is working at a
high internal signal level.

I presume the high effective noise level in a normal domestic audio is
because the DEQ2496 seems to be based on 3V / 10V levels? That isn't
necessarily a problem from my POV as the Armstrong 700 preamp I use can be
set to generate 10V output fairly easily. (It was designed in an era when
some of the USA high power amps needed to be given well over 1V to reach
their max output.)

And for digital sources I could feed them in via spdif or AES/EBU.

Also, my guess is that if I decided to use something like this I'd feed its
digital output to a seperate dac which would then give the more usual kind
of analogue output levels.

If using an equaliser I almost certainly wouldn't also use a sub. For me
the choice is an 'either/or'. The sub has the advantage of going to the
heart of dealing with any lack of LF sensitivity without affecting the main
signal path. The equaliser has the advantage of being able to deal with the
sense of 'boosted presence' I get with some recordings.

The alternative I have in mind for the latter is to simply DIY a simple
analogue box of my own. Not exactly rocket science, and no worries about
resampling, added noise, etc. Just mean the usual delays whilst I play
about and wait for the 'round tuits' to arrive. :-)

Something like the Behringer is interesting, though, purely out of
curiosity - and it also has some entertaining features like its displays,
metering, etc, so nice as 'eye candy' as as general exploration kit. I'd
probably end up blanking that all out, though... ;-

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

Quad ESL2805 [was: And so...]
 

In article , Serge Auckland
wrote:


The output sample rate follows the input rate, at least mine does! If
one's using the analogue inputs, then the output rate can be set to
whatever one wants. It won't act as a sample-rate converter, for
example taking in 44.1 and outputting 96k. As to dealers, I've bought
from Dolphin Music, Digital Village and GAK successfully with no
problems. I use mine at the input of my Meridian DSP 'speakers,
effectively at the input of the DAC.

It is quite likely that if I used one I'd add an external DAC like a
DACMagic or similar. The highest data rate I normally use is 24/96 and the
vast bulk of what I listen to is still CDDA.

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

Quad ESL2805 [was: And so...]
 

"Jim Lesurf" wrote in message
...
In article , Chris Morriss
wrote:
In message , Jim Lesurf
writes


Something like the Behringer is interesting, though, purely out of
curiosity - and it also has some entertaining features like its displays,
metering, etc, so nice as 'eye candy' as as general exploration kit. I'd
probably end up blanking that all out, though... ;-

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics
http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html


The metering is nice, in a rather depressing sort of way, as it indicates
all too obviously when CDs are clipped. There are some CDs that turn on the
"clip" indicator rather often.

S.

Quad ESL2805 [was: And so...]
 

"Chris Morriss" wrote in message
...
In message , Jim Lesurf

The DEQ2496 does offer a lot for the money and is a well known unit.

I would be wary of the SNR at the outputs though. My hearing is not at
all good any more, but the noise level when using one of these at low
output levels is not really adequate. The solution is to follow the unit
with a multi-channel analogue gain control (rather than using the internal
digital gain control), so that the crossover is working at a high internal
signal level.

I would say that a little different - the goal is to have the output of the
crossover working at a high level.

Inside the box, the digital data path is 24 bits wide, and you have misset
levels by a mile to have noise there.

At the output of the box, the transition into the digital domain is
designed, per pro standards, for FS = approximately 10 volts RMS (+22 dBu)

Most power amps have input sensitivities below 2 volts for full output, so
approximately 16 dB worth of available dynamic range are lost. The unit has
approximately 110 dB dynamic range, so losing 16 dB puts you down at 94 dB
which still isn't all that bad if you actually set levels that way. Many
people miss that goal.

Or, simply have power amps that have input level controls.

Four-way log pots are easily available, but for more ways you might have
to have a look at some of the kits that use Analog Devices digital pot
chips. I can vouch for the quality of these chips, as I use them in my PA
and VA amplifier designs for my employer.

Stepped attenuators will suffice, as will hand-built ones.

Quad ESL2805 [was: And so...]
 

In article , Arny
Krueger
wrote:

"Chris Morriss" wrote in message
...


I would be wary of the SNR at the outputs though. My hearing is not
at all good any more, but the noise level when using one of these at
low output levels is not really adequate. The solution is to follow
the unit with a multi-channel analogue gain control (rather than
using the internal digital gain control), so that the crossover is
working at a high internal signal level.


Inside the box, the digital data path is 24 bits wide, and you have
misset levels by a mile to have noise there.

At the output of the box, the transition into the digital domain is
designed, per pro standards, for FS = approximately 10 volts RMS (+22
dBu)

That was my understanding of the specs in the manual. Although it also
mentions +12dBu, but I wasn't clear if that meant both input sensitivity
and output level for 0dBFS could be set to that as an alternative.

Most power amps have input sensitivities below 2 volts for full output,
so approximately 16 dB worth of available dynamic range are lost. The
unit has approximately 110 dB dynamic range, so losing 16 dB puts you
down at 94 dB which still isn't all that bad if you actually set levels
that way. Many people miss that goal.

I would need to test the unit to really know, but my inclination would be
to always keep well below -6dBFS anyway since otherwise some internal
processes might overflow. All depends on the details of the internal
processing. With genuine professional gear I'd assume this isn't a problem.
But with 'prosumer' or 'amateur' - or 'audiophile' - I'd be more wary
initially.

FWIW It seems to me to make more sense in a domestic audio situation to use
something like the DEQ with digital in and out. Cuts down the number of
conversions, and also lets you use a consumer DAC which outputs the more
familiar (for home use) Phono/RCA with circa 2V for 0dBFS.

That said, I've still personally come to no conclusions about the need in
my case. I may well end up deciding that the Quads with my modified Quad 34
are still fine for me. May try a sub or something like the DEQ out of sheer
curiosity. :-) More likely I'll just be 'distracted' by listening to
music, though! Recent Proms have been great, and I've been ordering and
getting some more Jazz CDs. Perhaps I should start another thread about
that...

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html