New toy - not quite what you'd expect (graphic equaliser)

Man of Honour
Man of Honour
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Yep, you read that right, I'm having a play with a graphic equaliser at the moment.
Having said that, not the usual 80s stuff. Here's a pic:

deq2496_medium.jpg


and a link:
http://www.behringer.com/DEQ2496/index.cfm?lang=ENG

This is a pro-audio piece of kit, usually for use in recording studios. The side effect is that it doesn't get anything like the markup that's on most decent stereo kit, and the RRP is just £225. Mine was s/h, making it cheaper than most of my cables.

As a unit, well it's got a lot of functionality that'll I'll probably never use, but also has the ability to do parametric equalisation. In english, it can complete frequency range adjustments similar to an old graphic equaliser, which can be useful for dealing with troublesome room acoustics.
In hi-terms, graphics are usually bad news as they tend to screw over the sound quality along the way.
This unit can be put between a CD transport and DAC (or run as a DAC) and then completed ALL normalisation in the digital realm, meaning that the impact should be fairly minimal. The bad news is that whilst I'm waiting for a set of decent XLR leads to be made up, that I'm using optical cables. The result is a slight softening to the normal presentation along with a minor loss of definition. I'm hoping that the XLR replacement leads will resolve that, meaning that it'll be fairly benign in operation.

The next step will be to optimise it for my room, which I'm not too sure about yet, but am reading around options.
 
is that 19" rack mount???... :cool: :cool:

Niiiiiiiiiiiiiiiiiiiiiccccccccccceeeeeee!... I wish I had the room to built a pro-audio system!... plus the wif'd not be too happy!... "Sounds no different to me" is all I get whan I demo her stuff!!.. :(
 
Yep, it's a 19" rack mount.
Pro-audio kit is not something I'd usually play with, but it came well recommended, and I can probably sell if for close to what I paid for it if I don't like it.
The build quality is actually a bit cheap and nasty when compared to say my amp, but then it costs peanuts in relative terms.

I know what you mean by "can't tell the difference". My mother tells me that when she listens to my system after her own £200 Denon midi unit. Maybe I should have bought a PEP instead.
 
If it is parametric, USE IT! Dont use the graphic part of it!

Do you have a way of generating slow sine sweeps? This is the only real way to go about doing it properly - doing it with music is a bad idea :)
 
DRZ said:
If it is parametric, USE IT! Dont use the graphic part of it!

Do you have a way of generating slow sine sweeps? This is the only real way to go about doing it properly - doing it with music is a bad idea :)

Err, could you translate that into non-techie speak please. I am interested.
 
Ok :p

Graphic equalisers work by allowing you to set the gain over a set frequency range - usually in octave bands, the frequency you see being the centre frequency of that octave band. An octave is a doubling of frequency so you see bands like 63, 125, 250, 500, 1000, 2000, 4000 etc.

Thats all well and good for a general "curve" of the response of the room, but if you have a bad cabinet resonance at say, 48Hz, dialling down the 63Hz octave band is going to attenuate all of the frequencies in that band - thats bad for the frequency response!

Parametric equalisers let you set the exact frequency and Q value of the filter. This means that, to a reasonable degree at least, you can dial out specific frequencies. Remember that there isnt a perfect filter, they all have an order so surrounding frequencies will be affected (the further away they are, the less they are affected). I have never used a digital filter in the digital domain, but digital filters in the analogue domain tend to be pretty poor compared to analogue filters in terms of response etc.

Sine sweeps are just that, a sine wave that sweeps upwards in frequency at the same amplitude. There is software that will generate sweeps, some free, some costly. Adobe Audition will do it, but I have a freeware app that I got from one of the major download sites, CNET I think.

Slow enough, say a 30s sweep, you will be able to hear lumps in the response if there are any. Using that as your guide, removing the lumps will give you a much flatter response and therefore it will (in theory) sound better with these removed. Of course, your hearing plays a part in this! Take a look at "equal loudness contours" for say 70 phon. That is the "average" ear's response - far from flat! There is nothing you can do about that, so tinkering until you cant hear the lumps should be fine :)

One thing though, leave 1kHz alone - it is the reference frequency :)
 
My thoughts were to use a test disk that I have to conduct some frequency sweeps and try to do it by ear.
The 2496 does have parametric equalisation and can set itself up if you plug a mic in. Having said that, I've heard that it's better to do the job yourself.
From what I remember the frequency range that you can play with is variable.
 
Nice bits of kit these, been tempted to get one and have a play myself after reading so many favourable things about it at Zerogain. Problem is, my own knowledge in how best to use it is somewhat limited (need to get Tenson, 3dSonics or Isaac Sibson to have a go).

Using it in digital passthrough mode (acting as EQ only, not a DAC) would be my preferred method of operation in my setup, though I do worry about additional jitter and also the way some have said it 'kills the music' and makes everything a bit flat and lifeless (Isaac over at ZG uses it to help with speaker positioning and similar by measuring the frequency response with it, but doesn't have it plugged in all the time as whilst the EQ can do great things, especially at the low end, it doesn't sound very musical afterwards :().
 
Will said:
Nice bits of kit these, been tempted to get one and have a play myself after reading so many favourable things about it at Zerogain. Problem is, my own knowledge in how best to use it is somewhat limited (need to get Tenson, 3dSonics or Isaac Sibson to have a go).

Using it in digital passthrough mode (acting as EQ only, not a DAC) would be my preferred method of operation in my setup, though I do worry about additional jitter and also the way some have said it 'kills the music' and makes everything a bit flat and lifeless (Isaac over at ZG uses it to help with speaker positioning and similar by measuring the frequency response with it, but doesn't have it plugged in all the time as whilst the EQ can do great things, especially at the low end, it doesn't sound very musical afterwards :().

Never heard one, but you have echoed all my fears and preconceptions !!!!
From the reading I did, along with DRZ's help, frequency issues in room is best done with room correction, and not electronically, as it is only slightly useful at correcting low frequency, due to bass notes having a longer duration...A perfect resonce I think is not requirement in the grand scheme of things, a dam fine enjoyable musical performance is....
Mr_S I fear you have slipped to the dark side..... :( ..... I think some group therapy at your nearest Linn/Naim dealer is required to rescue you :p
Just think back to those Kaber days........keep saying it but you will have to find your way to sunny suffolk sometime !!! (Keltiks will have gone by then once someone bids !! :eek: )
 
9, what's next post the Keltiks? Didn't quite gel with them I guess.

Ref the Behringer. I'm using it between my transport and DAC via optical cables and it is NOT completely benign. Does't really "rob the life", but does defocus the sound a little.
Later this week a set of XLR terminated cables will be arriving from Zanash and I'll be trying those as my transport and the 2496 have appropriate XLR connectors for the digital side of things. I'll also be giving it a try as a DAC directly into my amp via balanced XLR connections. I don't expect it to outperform my BC DAC, but thought it would be interesting to give it a go.

Strikes me that it's a question of balance, i.e. whether the detrimental effect that it has upon the sound is made up for by the reduced bass bloom at room nodes. Right now, simply can't answer that, but I'll keep you posted.
 
Sure the right balance is an illusive thing, tried curing my “Bass Bloom” … in practice I think my room doesn’t have coincident nodes, just a few single nodes values. The use of bass traps only had a small effect, think it would take far to many in the room to have much effect…..

Did achieve a better result, with the Keltiks, by reducing the bass extension on the active cards. Cut them back to 40Hz….. now the room does get driven so much. Simply think I need a bigger room to benefit from real low bass….. Better power amps also helped the problem…. Tried them with my Klouts now !!!!
Re Keltiks, like them, sound very good, but think I can do better ..Akurate 242 may be.
If I’m not using the 20 – 40Hz ability fully why not focus on a better mid and top ?
Might go back to my active Dynaudio’s, better tweeter anyway, few more cabinet tweeks, and the use a better power amps….the new Chakra ones….
Then I could look at some Wilson Benesch, Dynaudio, Linn Akurates, and possible SEAS kit from Wilmslow Audio.....
 
I just picked one up this week, also (that's me who revived Issacs thread), and my reaction is mixed.

Using at just as a DAC, it's not much better than the analogue output on my G5. But hey, you don't buy a DEQ because it's a great DAC (and I certainly don't plan on modding it), you buy it for the room correction :)

I'll pick up a callibration mic as soon as I can, and give that a shot. :)
 
bit of a bump,

have you given this a go ?

I managed to borrow a decently calibrated SPL Meter & as I suspected I have some hideous peaks in my cinema room at low frequencies, sub has been moved all over the place & there is no way I could fit enough bass traps in the room to kill it.

I'm thinking about fitting one of these inline with my sub to try & flatten the response out a bit, just wondering how you have got on with it ?
 
Since getting the unit, I've also got some much better interconnects, so that I can use XLRs for AES/EBU digital input and balanced output to my stereo amp.
It certainly doesn't sound rubbish, though it's not as good as my normal dac. For the price however, it's good value (bear in mind that the RRP for my DAC was 6 times that of the 2496, and my DAC has none of the additional functionality).

I've just moved, so haven't had much more time to play with it, hope to be able to do so in the next couple of weeks.
 
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