Dry bass

[Deleted member 48726]

I've seen numbers on other forums IR to live gig subs like +20 dB. No wonder people can't fathom what is needed to recreate that.

Lot of power.. Lot of air movement.

 

[Zapper]

It isn't. It is defined by the RT30/RT60, and spectrogram and waterfall plots. Or a long bass tail at the end of an impulse response.

For quite a long time, I believed that "dry" bass sounds "tight", as in - after a transient kick like a bass drum, the note ends and decays into nothing. This was why I chose Rythmik subwoofers. But lately I have been struggling to understand why my bass lacks impact, and I was wondering whether its dryness had something to do with it. Hence why I started the thread.

So "dry bass" is associated with rapid decay / short RT30/RT60?

 

[dasdoing]

first time I heard of someone in a big room wanting a small room sound lol

Several reverb plugins emulate early reflections

 

[Keith_W]

So "dry bass" is associated with rapid decay / short RT30/RT60?

Yes.

first time I heard of someone in a big room wanting a small room sound lol

Several reverb plugins emulate early reflections

This "someone in a big room" spent too much money on his house and not enough on his hifi system and he's too cheap to buy bigger subwoofers

 

[tinnitus]

@Keith_W
can you expand your pulse respond. And your step respond looks ugly. Your rt60 is good, if you change to studio you will see it.
I have a very dry bass with good punch. For this, 4 ten-inch woofers work on each side.

 

[Bjorn]

RTx measurements are invalid in small rooms.

And again, the waterfall doesn't show "dry bass" at all. When especially the mid and upper bass is ringing and decays slowly, what you're describing is exactly what you get.

Even smaller speakers can achieve an experience of impact and some slam if the time domain behaves well enough. The subjective experience of start, stop and weight is something entirely else.

 

[Deleted member 48726]

Yes.



This "someone in a big room" spent too much money on his house and not enough on his hifi system and he's too cheap to buy bigger subwoofers

You think you gonna get big sound with small drivers then?

 

[tinnitus]

RTx measurements are invalid in small rooms.

And again, the waterfall doesn't show "dry bass" at all. When especially the mid and upper bass is ringing and decays slowly, what you're describing is exactly what you get.

Even smaller speakers can achieve an experience of impact and some slam if the time domain behaves well enough. The subjective experience of start, stop and weight is something entirely else.

What is a small room? 7x6x3 meters.

 

[3ll3d00d]

I have read and re-read your post #16 in this thread about resonant filters and using two shelf filters on the same channel. I think I am starting to understand, the overshoot from the overlap of the two curves will somehow cause the sub and the woofer to resonate more, which will "wetten" the lower frequencies, thus creating bass punch? Or am I wrong here?

it's just a standard IIR filter so adjusts the frequency response, a higher Q shelf filter just means you get a steeper slope and some overshoot at either end of the shelf (which is akin to putting a couple of peaking filters at either end). You can add them in jriver PEQ without having to fiddle in acourate or using some VST.

 

[Bjorn]

What is a small room? 7x6x3 meters.

It's frequency dependend but Manfred Schroder defines the following: A large room for speech with a low frequency limit of 80 Hz is = to or >991 m³ (35,000 ft³) and a large room for wide range music with a low frequency limit of 30 Hz is = to or >7079 m³ (250,000 ft³).

So all rooms in a home is acosutically a small space for music.

 

[Sokel]

Sometimes I feel that people in here don't go around listening.
What subs are you're talking about?

Slam needs zero subs.Zero.
All it needs is a nice more than 10" driver in a big cabinet crossed between 250-500Hz to a mid.

Remember this old broad speakers with their big drivers that went down to 40-50Hz at the most?They could kick like donkeys in your chest.
Experienced any PA kicking you?Doesn't do 30s' either,but it does do a whole big 80-250Hz big time,that's where this energy is.

Just watch at RTA of a song with a good kick and see where things happening,is as simple as that.

 

[Kvalsvoll]

Sound field properties relevant for low frequency reproduction

This will be an excerpt from a text I made 5 years ago, intended for a series of technical articles on bass and calibration.We need this to understand the \"Case: …

www.kvalsvoll.com

This gives some insight into why bass can be experienced very different even if measured frequency response is equal. The text is incomplete, so bear with me here, this is what there is.

So, after frequency response is reasonable, i.e. no huge resonances or missing parts, and timing/impulse is decent enough, it still may sound, well, not so great.

What can be done? Move listening position, move subwoofer units and calibrate (both eq and individual delay). Though, in this case, I also suspect the subwoofers may be inadequate.

 

[Sokel]

Those huge dips? I suspect that's the room, not the crossover. I realize that the x axis markings are a bit difficult to see. Acourate does not boost dips, it only cuts peaks. I chose not to cut the peaks too much because (as you can see from the depth of those dips) I would lose a lot of volume. And yes, the drivers are wired up correctly. Here is the set of crossovers, with driver correction, time alignment, phase correction, and room correction baked in. Overlaid on top (black curve) is the sweep.

View attachment 333143

I don't think a room can do that up there,no matter how big,mine is more than double than yours and looking around seeing other people's measurements I never saw such a thing.
This looks a LOT like a driver put in the wrong polarity after some odd crossover.

 

[dweeeeb2]

I don’t have any experience with this really so feel free to ignore but I’m of the thinking that the impact of transients such as drums is just a function of FR at different volumes. ie for best sound the FR curve at 90db should be parallel to the FR curve at 80db (for example) any dips will sound like that frequency is lacking punch. A bit like Erins compression graphs. If this is making any sense try a sweep at your listening volume and then another 10db lower.

 

[Sokel]

I don’t have any experience with this really so feel free to ignore but I’m of the thinking that the impact of transients such as drums is just a function of FR at different volumes. ie for best sound the FR curve at 90db should be parallel to the FR curve at 80db (for example) any dips will sound like that frequency is lacking punch. A bit like Erins compression graphs. If this is making any sense try a sweep at your listening volume and then another 10db lower.

You're absolutely right about it.
The ability of high level true peaks without clipping,compression or limiting like some EQs do is without saying.

 

[mcdn]

I don't think a room can do that up there,no matter how big,mine is more than double than yours and looking around seeing other people's measurements I never saw such a thing.
This looks a LOT like a driver put in the wrong polarity after some odd crossover.

Exactly - in this quite large room 500hz is way above the transition frequency. @Keith_W you reallly do need to take an independent measurement with REW using the moving mic method. If you have a polarity issue it could even be that your mains and subs are fighting each other at 80hz…

 

[ernestcarl]

I am not sure where the blame lies. For those systems that have impactful bass, they were all using much bigger subwoofers than mine - one guy has four 15" subs, and another has two subwoofers, with each subwoofer containing 3x 12" drivers. So I am not sure whether my result is due to using smaller subs, or whether it is because my bass is too dry.

It would be illuminating if you had the IR measurements taken at their own rooms as a sort of benchmark reference and compare that to your own.

 

[NTK]

@Keith_W You may want to take a look at this white paper by Nyal Mellor and Jeff Hedback. (Mellor got an endorsement from Amir.) In particular, your low frequency decay time seems longer than the recommended <0.35 s (decay to -40 dB), and therefore your bass may be less dry than you think.

Acoustic Measurement Standards for Stereo Listening Rooms published

Some of the many questions that can be found scattered across the internet and overheard in conversations amongst audiophiles today relate to room acoustic measurements: What are the key measurements? How do I interpret them? What does good look like? How do they relate to each other? These...

acousticfrontiers.com

 

[Chrispy]

Read some....but wtf is dry bass let alone wet bass particularly in technical terms?

 

[Keith_W]

I don't think a room can do that up there,no matter how big,mine is more than double than yours and looking around seeing other people's measurements I never saw such a thing.
This looks a LOT like a driver put in the wrong polarity after some odd crossover.

This is the unwrapped phase of the system from 10Hz - 24kHz. I have zoomed in to +200deg / -2000deg. If the polarity of the mids was inverted at the crossover point, you wouldn't expect to see the smooth phase change, is that correct?

@Keith_W
can you expand your pulse respond. And your step respond looks ugly. Your rt60 is good, if you change to studio you will see it.
I have a very dry bass with good punch. For this, 4 ten-inch woofers work on each side.

I am not quite sure what you want to see with the pulse response. By "expand" do you mean, "zoom in", or "display a longer time scale"? Here are both anyway:

You can see individual jaggies corresponding to the limit of resolution of the 48kHz sampling rate, which is 0.208ms. This is zoomed in to a 4ms window.

And this is zoomed out to a 100ms window.

And yes, I did see that the bass is within target for studio, but then everything above 200Hz is above target. Regardless, either the bass is too dry, or everything above 200Hz is too wet. Subjectively, I like the sound of everything that is 200Hz and up so I am more inclined to focus on the bass.

Read some....but wtf is dry bass let alone wet bass particularly in technical terms?

Too little reverberation = "dry". Too much reverb = "wet". Or in the graph above, if the RT60 is below the target it is too dry, if it is above the target it is too wet.