Using a High WAF Design to Block the Back Wave

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Command central.:music:

bd180.jpg


"Engage"... Jean Luc Picard should have that much control over the Enterprise ;)
 
Speaking of which: $10 million for a Tricorder

I use a laptop as a source so can apply EQ digitally. Speaking of which WMP's digital effects/eq just sound attrocious. Some achievement! SRS Wow? Yuk.

I'm sure there is much better s/w around for EQ than that particular offering.
 
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Justin, as someone who can alter the FR of his system at will, IME the hardest thing to get right is the 6-20kHz region. I'm constantly tweaking it to varying levels of dissatisfaction. To make matters worse and because there are no studio standards, FR varies from recording to recording, so that what sounds terrific with albums A-M may sound flat and lifeless for albums N-Z. There are no ideals and, yes, it's all subjective.

It'd be nice if you could set EQ up on a per album basis - then get it to switch automatically with each album change selected in a player.:)
 
As high as 4db in variation with tube rolling? Yikes. I'll stick to solid state. I don't need any more variables in the equation. haha

That's absolute worst case and only over a small part of the frequency spectrum. Overall, when viewed at the same level as the first graph I posted, they're all fairly close. But nonetheless different:D
 
It'd be nice if you could set EQ up on a per album basis - then get it to switch automatically with each album change selected in a player.:)
Album by album is a bit of a stretch, but I have 9 presets, each of which I've set up with slightly different emphases on LF/HF, so I can usually find one that sounds subjectively good.

As Toole has repeatedly pointed out, we need standards for music like those for film. Absolutely zero signs of that happening, alas!
 
Here's the bass response, set at 24 ppo, for 20-200 Hz. The red curve is with no traps while the blue is with traps.

BassResponse.jpg
 
Bass decay with traps. I noticed that without the traps the curves varied a lot from sweep to sweep, whereas with the traps it was fairly consistent from sweep to sweep.

BDecayWithTraps.jpg
 
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Bass decay with traps. I noticed that without the traps the curves varied a lot from sweep to sweep, whereas with the traps it was fairly consistent from sweep to sweep.

View attachment 15126
Not bad, at all!

Here's the bass response, set at 24 ppo, for 20-200 Hz. The red curve is with no traps while the blue is with traps.

View attachment 15124
I'll bet you've got a room dimension right around 16', no? Within the Mellor/Hedbeck guidance (+/- 10dB @ 1/24th oct; +/- 5dB @ 1/3rd oct), though more linear will sound subjectively better. Corner bass traps, if practical, would help, esp. in the mid-bass. Note that the two frequency peaks in the 30's and 50's mirror the decay peaks in the frequency response. If you could lower those peaks, the corresponding decay times would also decrease.
 
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The room dimension is more like 14'.

Unfortunately bass traps in the corners are not an option. The only thing I could do is rework the traps I built, filling them with stuff, but I don't know if that will help. I bought Toole's book, and need to read it before doing more experimenting. BTW, thanks for your help - I have learned a lot.
 
...The only thing I could do is rework the traps I built, filling them with stuff, but I don't know if that will help.
It really won't do anything for the bass response, though it might further reduce the ETC spike for the rear wave, if you want to chase that.

My pleasure, Bernard.
 

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