Measure your C50 in REW and tell us how your bass sounds!

[NIN]

Thanks. Still looking for improvements but because it is a "normal" living room there are limitations to what I can do. I have still not played with DSP for the bass.

 

[mydust]

很好的参考！

 

[Hexspa]

I don't know how to interpret the clarity measurements but here are mine. Please note that I took another measurement for the decay and waterfall plots because I had higher ringing ~120Hz that reduced 3-4dB the second time.

Bass decay shows impulse, 140 and 160ms, waterfall shows about 30dB on y-axis, full spl is variable smoothing, bass spl is no smoothing, impulse response envelope and clarity graphs are what they are. I only measured from 27Hz because that's A0 in musical terms and my sub doesn't play with accuracy to that range anyway.

This is post-EQ from 18 measurments around my listening position, nine in a grid then nine more at seated height, averaged then placed into EqualizerAPO. Speakers are Yamaha HS50 with HS10w subwoofer (quoted -10dB @ 30Hz) @ ~1m with a calculated level from REW of 74.4dB in a treated space of ~2500ft3 and irregular shape.

How does my bass sound? I take you to mean with the mains because without them it sounds just like a subwoofer. It sounds spacious, accurate and flat, slightly elevated but not overwhelming. My taste is not to have a ton of bass so it's fine. This calibration is for music creation more than enjoyment and a similar calibration I used before this worked well, allowing me to achieve the "translation" that audio people chase, as least in the low end. My plan is to swap out my mains when I can.

Let me note that 120Hz is a problem frequency for me right now. I had to use the high pass filters on my mains to 80Hz to get the most even response at that range. I tried 100Hz and inverting the subwoofer's polarity but none of that worked. Quarter wavelength is around 2' so I think it's either a desk bounce and/or a front wall reflection; I have no absorption behind the speakers except for two floor-to-ceiling 32"-wide fluffy superchunks in the corners. If I look at the minimum phase generation, I'm pretty sure it's not flat right there either. As far as I know, that means EQ is less effective there and that could be why there's more decay.

 

[Flaesh]

I don't know how to interpret

In this case, the interpretation is trivial - the result is good and sufficient, because

@ ~1m.. in a treated space of ~2500ft3

From a greater distance, smaller values of C(D) can be measured (and heard), down to an inarticulate bass in ordinary rooms

 

[Hexspa]

In this case, the interpretation is trivial - the result is good and sufficient, because

From a greater distance, smaller values of C(D) can be measured (and heard), down to an inarticulate bass in ordinary rooms

Thanks for your response. Can you point me to a good resource on understanding these Clarity graphs? The REW help says it’s the ratio between direct and ? sound in dB but I’m not sure if lower or higher is more “clear” and why the lines would not be horizontal whether they should conform to a certain shape or what importance wiggles in the lines have. Thanks.

 

[Flaesh]

I think there is some discussion in this thread. As a metric of the quality of bass reproduction, these indicators are not generally accepted and are quite rough.
See also discussions about MATT test aka Stereophile Test disk 2 track #11.
Ideally, the D50 graph line is approximately horizontal between 99% and 100%
BTW here's an ordinary sound card:

 

[Hexspa]

I think there is some discussion in this thread. As a metric of the quality of bass reproduction, these indicators are not generally accepted and are quite rough.
See also discussions about MATT test aka Stereophile Test disk 2 track #11.
Ideally, the D50 graph line is approximately horizontal between 99% and 100%
BTW here's an ordinary sound card:
View attachment 340251

Thanks for this. I'll check out MATT and review this thread. Cheers.

 

[Ollie99021]

My Setup consists of Revel F226Be, x2 Rythmik E15s, Benchmark AHB2 & DAC3L, SMSL PO100, I7 laptop running Audirvana upscaled x2,x4 to 176/192 VST3 HLC, EQ and phase adjustments with REW and Rephase with convolution filter. Semi treated medium sized open basement living area located in unsymmetrical part of the room approximately 9 feet from speaker to MLP, 27'Wx14'Lx7'10"C opens up to more to sides of listening area, Rspkr 6' from right wall. Have a serious ~60hz dip on right channel. Looking for any comments - RT60 is definitely not as good as some here, may need more treatment (RT60 350) and the upward tilt >10k is intentional, EQ 10hz-6k boos<3db and rephased closer to flat >200hz. Probably more than necessary info. Curious if any thoughts on my measurements or improvement ideas. Sounds great, better than my Arya hps, really tight imaging vertically and horizontally, good texture in the bass and clear but I am discovering that until you hear it you just don't know how good it can get. Measurements are both speakers and subs.

can always learn something.

 

[Tim Link]

My Setup consists of Revel F226Be, x2 Rythmik E15s, Benchmark AHB2 & DAC3L, SMSL PO100, I7 laptop running Audirvana upscaled x2,x4 to 176/192 VST3 HLC, EQ and phase adjustments with REW and Rephase with convolution filter. Semi treated medium sized open basement living area located in unsymmetrical part of the room approximately 9 feet from speaker to MLP, 27'Wx14'Lx7'10"C opens up to more to sides of listening area, Rspkr 6' from right wall. Have a serious ~60hz dip on right channel. Looking for any comments - RT60 is definitely not as good as some here, may need more treatment (RT60 350) and the upward tilt >10k is intentional, EQ 10hz-6k boos<3db and rephased closer to flat >200hz. Probably more than necessary info. Curious if any thoughts on my measurements or improvement ideas. Sounds great, better than my Arya hps, really tight imaging vertically and horizontally, good texture in the bass and clear but I am discovering that until you hear it you just don't know how good it can get. Measurements are both speakers and subs.View attachment 371145 View attachment 371136can always learn something.
View attachment 371135View attachment 371141

Clarity looks very good. I don't know if it would sound better to damp it down further or not. You'd have to try it and decide. Your room clarity looks very similar to mine, except yours is better below 200 Hz. I think my room sounds really good above 200Hz so I'm not inclined to add more absorption. I had some Revel M16 at one time in this room and they made the room sound overdamped. Not sure why, but my current setup that's all horns doesn't come across that way. I percieve it as more lively even though it has a considerably higher directivity index. So, I think it's hard to say exactly where that RT60 should be. Cn you include the RT60 too? Just curious to see it. Mine hovers around 280ms except in the bass, where it gets up to 600.

It is interesting that you've got such a very flat response from 200Hz on up. My latest settings have me at a 1 dB/ octave slope at the listening position, which is surprising to me but sounds good. I've had some very flat response in recent times. This occured more by accident than intentional, as a result of crossover settings. It was intriguing in some ways but overall too bright for me.

 

[Ollie99021]

Clarity looks very good. I don't know if it would sound better to damp it down further or not. You'd have to try it and decide. Your room clarity looks very similar to mine, except yours is better below 200 Hz. I think my room sounds really good above 200Hz so I'm not inclined to add more absorption. I had some Revel M16 at one time in this room and they made the room sound overdamped. Not sure why, but my current setup that's all horns doesn't come across that way. I percieve it as more lively even though it has a considerably higher directivity index. So, I think it's hard to say exactly where that RT60 should be. Cn you include the RT60 too? Just curious to see it. Mine hovers around 280ms except in the bass, where it gets up to 600.

It is interesting that you've got such a very flat response from 200Hz on up. My latest settings have me at a 1 dB/ octave slope at the listening position, which is surprising to me but sounds good. I've had some very flat response in recent times. This occured more by accident than intentional, as a result of crossover settings. It was intriguing in some ways but overall too bright for me.

Thanks for the feedback. Attached is my RT60 which sounds like it is much higher than your RT60. Mostly in the 400s and in bass gets quite high.

I think running Rephase adjusting for crossovers and making the speaker to speaker phase flattish and <+/-15 degrees apart 200hz up helped clarity a bit. The flat frequency response was intentional although I may add some slope. My hearing isn't what it used to be. Need to rerun EQ etc. and do some comparisons. Look forward to any thoughts you may have.

 

[Tim Link]

Thanks for the feedback. Attached is my RT60 which sounds like it is much higher than your RT60. Mostly in the 400s and in bass gets quite high. View attachment 371596I think running Rephase adjusting for crossovers and making the speaker to speaker phase flattish and <+/-15 degrees apart 200hz up helped clarity a bit. The flat frequency response was intentional although I may add some slope. My hearing isn't what it used to be. Need to rerun EQ etc. and do some comparisons. Look forward to any thoughts you may have.

That is interesting. You've got good clarity despite a higher RT60 time, especially between about 600 Hz and 2 kHz. I imagine that probably sounds really nice! Without seeing further detail, I'm guessing the initial sound is relatively loud compared to the reverb tail. So even though there's a longer reverb time, it doesn't dominate the direct sound enough to murk it up.

 

[Ollie99021]

Not exactly sure why but it does sound great despite the higher RT60 - maybe what you suggested. Imaging is great both vertically and horizontally and sounds really clear to me with good texture in the bass.

I definitely noticed a jump in quality adding some acoustic treatment on the ceiling, front and back wall. I haven't done anything to the side walls yet but may add some at the reflection points on the closest wall to see if I notice an improvement or if it measures differently. I am always tweaking so if I make a significant improvement I will post again. Cheers!

 

[rvsixer]

Most of the references I found for clarity on the web, had to do with large spaces/venues. I stumbled upon a paper that had interesting research regarding clarity in our domestic sized spaces/listening distances:
https://www.acoustics.asn.au/conference_proceedings/ICSV14/papers/p328.pdf

Back to OP request. Here's my before and after C50 clarity graph (uppermost data is completed/treated/optimized 80/20% HT/2ch room, lowermost data is empty room with only basic initial MLP/speaker/sub setup in it).

Room is 13.7 x 12.5 x 9 ft, asymmetric with several alcoves (i.e. a bad room). Best possible/probable MLP/speaker locations were discovered by doing an SPL heat map of the room before build (room mode calculators and setup rules-of-thumb such as sit 38% from back wall need not apply, they were all WAY off). Basic but decent equipment (Arendal 1723 bookshelf S LCR, Arendal 1961 bookshelf surround/Atmos, Denon X4800H AVR, dual DIY sealed passive subs w/Crown XLS1502). Absorptive GIK treatments, supplemented by a huge DIY R19 2' deep x 8' long fluffy fiberglass trap above the closet alcove (really helped with two horrendous 42/48Hz room modes). Dip in left/right clarity at 625Hz is due to the 83" TV between the mains (TV is on an extending wall mount, and can be moved out of the way for more serious 2ch listening; the mic says its sounds better but my ears say its fine either way). The initial 200Hz area clarity dip was side SBIR, improved through lots of panel placement experimentation, resulting in assymetric placement of side absorbers which was new for me.

Bass before was meh, bass in completed room is wonderful. Ditto for the rest of the auditory experience.

In the next couple of weeks hope to have four new/larger DIY passive sealed subs completed and installed (goal is to extend the great bass across the entire sofa and dig deeper). Will post if clarity results are significantly better (or worse).

 

[Tim Link]

Most of the references I found for clarity on the web, had to do with large spaces/venues. I stumbled upon a paper that had interesting research regarding clarity in our domestic sized spaces/listening distances:
https://www.acoustics.asn.au/conference_proceedings/ICSV14/papers/p328.pdf

Back to OP request. Here's my before and after C50 clarity graph (uppermost data is completed/treated/optimized 80/20% HT/2ch room, lowermost data is empty room with only basic initial MLP/speaker/sub setup in it).


View attachment 400494


Room is 13.7 x 12.5 x 9 ft, asymmetric with several alcoves (i.e. a bad room). Best possible/probable MLP/speaker locations were discovered by doing an SPL heat map of the room before build (room mode calculators and setup rules-of-thumb such as sit 38% from back wall need not apply, they were all WAY off). Basic but decent equipment (Arendal 1723 bookshelf S LCR, Arendal 1961 bookshelf surround/Atmos, Denon X4800H AVR, dual DIY sealed passive subs w/Crown XLS1502). Absorptive GIK treatments, supplemented by a huge DIY R19 2' deep x 8' long fluffy fiberglass trap above the closet alcove (really helped with two horrendous 42/48Hz room modes). Dip in left/right clarity at 625Hz is due to the 83" TV between the mains (TV is on an extending wall mount, and can be moved out of the way for more serious 2ch listening; the mic says its sounds better but my ears say its fine either way). The initial 200Hz area clarity dip was side SBIR, improved through lots of panel placement experimentation, resulting in assymetric placement of side absorbers which was new for me.

Bass before was meh, bass in completed room is wonderful. Ditto for the rest of the auditory experience.

In the next couple of weeks hope to have four new/larger DIY passive sealed subs completed and installed (goal is to extend the great bass across the entire sofa and dig deeper). Will post if clarity results are significantly better (or worse).

Wow, that's quite a change with the treatment, going from pretty bad to exceptionally good in terms of clarity. That looks like a really reverberant room to start with, at all frequencies. Hopefully I'll get a chance to read that paper you linked to tonight.

 

[TheZebraKilledDarwin]

View attachment 400494

For a reflection of human hearing 1/3rd octave points are recommended. IMO bars work better for visualizing the smoothness.

 

[rvsixer]

Wow, that's quite a change with the treatment, going from pretty bad to exceptionally good in terms of clarity. That looks like a really reverberant room to start with, at all frequencies. Hopefully I'll get a chance to read that paper you linked to tonight.

To clarify, the graph/impressions I posted were for "empty room" to optimized/treated. "Empty room" being initial LCR/sub placement, before room buildout, no TV installed (but with basic Audyssey calibration to set delays, subwoofer crossover, etc.). And you called it...the "empty room" was at T60M of ~550ms from 200Hz up (going up to 1.4s in bass direction, and with a quickening drop-off after 3kHz).

Here's are graphs of the room after buildout but no treatment installed (with final speaker locations, TV mounted in place, verifying delays/crossover via impulses, phase, nice smooth peak energy line at sub crossover (REW spectrum wavelet)); and with final treatments added. Also associated T60M before/after treatment:

 

[rvsixer]

For a reflection of human hearing 1/3rd octave points are recommended. IMO bars work better for visualizing the smoothness.

Please clarify. The controls section has c50 1/3 octave points selected, or am I missing something else? I always prefer lines over bars visually, but will try the bars and see if I can see smoothness better.

UPDATE: Just tried the bars still doesn't work for me. Does this really look smoother/clearer than the otherwise identical lines graph above?:

 

[TheZebraKilledDarwin]

Please clarify. The controls section has c50 1/3 octave points selected, or am I missing something else?

1/3rd octave is good.

I always prefer lines over bars visually, but will try the bars and see if I can see smoothness better.

UPDATE: Just tried the bars still doesn't work for me. Does this really look smoother/clearer than the otherwise identical lines graph above?:

The goal is smoothness and the bars show differences in neighbouring frequency ranges more clearly.