BBV's Room Measurement Saga Continues...

I think the PEQ was at 88Hz and... I forget where else.

By all means try it flat but don't forget the point is to enjoy the music! I rarely find a completely flat response sounds as good as a gently shaped one. Usually to the equal loudness curve @ 80dB.

I'm not sure what he point in posting the EQ settings would be, but by all means do!

Also consider that removing the 'acoustic lens' on the tweeter may simply make the off-axis response less even, not more directional. I did find that it gave more detail though. But as you know my room is pretty well controlled.

 

Indeed - the vice like grip of your acoustic enhancement units!

Is there any point to tweaking out the remaining bass peaks and troughs or would that be optimising the listening position at the expense of the rest of the room?

 

By the way Nick that Frente album is forking brilliant! Love it

 

Did you just rip that cd or did you do the soundtrack as well? I want to compare your deq with mine soon...

Many may find it hard to beleive I listen to music

 

Nah optimise away, just don't use huge amounts of gain if you can. The point where it has 12dB is a lot already. I think you are getting a bit obsessed with a perfectly flat response.

Oh no I forgot to rip that other one. No matter it was for Kev anyway! Will you be at the show? Could give me a copy then?

 

Which show?

Yes I was worried about the huge amounts of eq - maybe we can shave it down a bit. I am not being obsessive about The Flat Response (I leave that to others) - just trying to understand the boundaries and what makes a difference. I assume its the slower changes that are important accross the frequency range - the envelope as it were.

 

I don't know which show yet lol! Are they close enough to nip between both?

Absolutely, slow changes seem to make a bigger difference. Its a good idea to have a play around and find out what doing different things sounds like. It is worth looking at the measurements on your computer so you can relate the sound to what it looks like as well.

 

Both what? I am thoroughly confused.

 

Both Hi-Fi shows in 2 weeks time. Heathrow.

 

I see - one is beginning april what is the other one?

 

Hi,

Just a note, I found it desirable to use the DEQ mainly to attenuate, if you boost any band significantly you need to set the overall gain by the amount of boost lower or there will be a CD which will have something there and which will clip the DEQ in the digtal domain, not nice.

I tend to restrict myself to no more than 6db boost.

Ciao T

 

Yes we lowered the digital gain from 0db to -12db so it wouldnt clip. Though conceivably the PEQ might tip the GEQ over that so I need to check tonight.

 

I don't think it will tip it, it was only used at points where the GEQ was not able to 'get at' due to its coarse frequency adjustment.

I normally restrict myself to 8dB gain but there was just one point on nicks system (40Hz I think) that needed it. He does have lots of power and bass capable speakers though so I didn't think it would matter too much.

 

Indeed if I hook up the xbds the headroom is 126db!

 

At what frequency?

 

126db is peak spl - I assume for white noise.

 

Well, just don't use that figure to calculate any max EQ settings.

Better to look at it as adding the XBD (and twice the power-amp) will give you 6dB more headroom for EQ.

 

When I used the DEQ to EQ my system the amounts of correction were huge. This was with the mic placed at head height and at the main listening position. While is certainly sounded neutral I also found it flat and boring to listen to over a period of time. The solution was to use the DEQ auto derived settings as a guide - I kept the response trend but limited any cut and lift to about 5db.

90% of my music collection sounds great without the DEQ in circuit, but some material, mainly dance and reggae sets the room off at 40-50hz and the DEQ therefore only goes into circuit for problem recordings. The real solution is clearly proper room treatment and I've made a start down that road with one of those big perforated wooden coffee table with the removable lid. It sits in a corner filled to the brim with old hi-fi mags and does a decent job at absorbing excess LF. At last a use for those hi-fi mags

I really must look into using the DEQ as a DAC at some point.

It's amazing Just how many people pay little attention to room acoustics when it has a huge effect on performance - equal to any speaker or source change, but will happily pay thousands for the dubious benefits of audiophool cables costing many hundreds of pounds.

The rot set in when the hair shirt brigade hijacked the audio industry in the 80s and removed tone controls

Rob.

 

EQ Settings

Freq R L

20 0 0
25 -2 -5
31.5 -12 -8
40 +12 +9
50 +4 +6
63 +1.5
80 -13 -9
100 -1.5 0
125 5 3
160 2.5 -0.5
200 2.5 -0.5
250 1 -1
315 0 0
400 0 0
500 -3 -3
630 -8 -4
800 -4 -1
1000 -1.5 2
1250 -1.5 1.5
1600 0 +1
2000 -1 0
2500 2 2
3150 -3.5 -2
4000 -2 -2
5000 -2 -2
6300 -2 -2
8000 -2 -2
10000 -2 -2
12500 -2 -2
16000 0 0
20000 0 0

and for peq

88.3 1/5 octave +3.5
72.6 1/5 -3
36 +3.5

Obviously the last peq is closely enough to the 40 hz value that we are probably getting +15 db eq! Digital gain was only set to -12db which means there is a chance of digital distortion.

So I plan to delete the last peq and limit the eq at 40 hz to 9 db setting the gain to -10db.

I will also level down 1-2khz and 10 khz by a couple of dB and lift 125 to 250 by a couple of dB.

 

BTW, if you move your listening seat forward or back a few inches you should find you fill in some of that bass null making it less odvious to the ears. Eq'ing it will usually be a waste of energy.