What compromises would you make?

Which of the following parameters would you let go of first?

  • maxSPL

  • low-end

  • group-delay

  • distortion


Results are only viewable after voting.
It's time for a little thought experiment.

Let's say you've settled on a certain active loudspeaker design.
The dimensions are set, the choice of drivers are chosen as well.
It's not possible to make any changes there.
Also the type of system is fixed.
For those who find this a little bit to abstract, lets just settle on a closed box system.
Let's say it's just a subwoofer or FAST system for now (I might make another poll for 2-way or mutli-way systems)

However, you want to squeeze out a little more performance out of the system.

In this world, nothing is for free, so this means we have to compromise.
Which parameter would you let go of first?
Aka, do you think is least important so you can improve the others?

maxSPL, low-end (how low the speaker will go), group-delay or performance in distortion?

Ideally tell us why as well with context. :)
 
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You realise it's difficult to rate them in the way shown in the poll, and you say this.. since it depends.

However if we want to talk about something consider low end extension. Multiple subs can build from the bottom up. Meet somewhere around the bottom of the vocals or the Schroeder frequency. Having mains flat to 20Hz has greater cost than benefit.
 
@AllenB
I am talking about just one single speaker design.
So no multi-sub or anything else, just as is.
But yes, you're right in a general sense, but that is not what this is about :)

The reason why I named those 4, is because they fall within basically the 4 parameters one has to make a compromise in within a design.

Or in other words;
  • If I want more SPL (from the same design), I have to let go of low-end (and maybe distortion).
  • If I want to get a better group-delay of the system, I have to let go of maximum SPL and sometimes low-end
  • If I want best distortion performance, I just can't go as low and loud

etc etc

In the end it's about the creators taste what direction to pick and how a design will perform eventually.

Out of those four, my pick would be probably group-delay.
Since in my experience it's the parameter that most people don't seem to care about that much in general.
And rather would have a bit more bottom-end or more SPL.
 
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stv

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Interesting subject!
I very much would like to hear the results of changing these parameters in person ... so right now: no idea.

However, for example, I would sacrifice low end below 40 Hz but rather not (much) above.
It also very much depends what the speakers are intended for. I would not sacrifice max spl for a party system.
 
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I agree it's too vague ( despite i answered the poll :) ): STV example is spot on, i can live with no lower octave but not much higher. I could live with distortion on this same lower octave if spl and group delay are met...
 
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I agree it's too vague ( despite i answered the poll :) ): STV example is spot on, i can live with no lower octave but not much higher. I could live with distortion on this same lower octave if spl and group delay are met...
That's exactly the reason why I asked for explanation and context ;)

Because yes, it obviously always depends on the use case and that is why it is so interesting :)
But in your case you would rather have the lowest group-delay as possible instead of less low-end?

edit; I might constrain the use-case a bit further, but we will just see how this goes :)
 
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That's exactly the reason why I asked for explanation and context ;)

Because yes, it obviously always depends on the use case and that is why it is so interesting :)
But in your case you would rather have the lowest group-delay as possible instead of less low-end?

edit; I might constrain the use-case a bit further, but we will just see how this goes :)

Yes i would favour group delay as long as spl requirements are mets. Low end extension i can 'see' through analysis visual program if needed and i feel distortion in low end is most often not disturbing ( if reasonable amount of course! Can even be pleasing and bring pleasing things - slam- to reproduction).

But that's my preferences. Others are as valid as mine.
 
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For a HT subwoofer I don't care for group delay that much. It is more a factor on the side line, giving some idea about the chassis matching the construction.
With HT you do not know how a low frequency effect "should be". Most important is the shaking "effect" it generates in the room. So the explosions pressure wave may come somehow late, but who cares.
With music things are a little different. We may know how the low note has to sound. Anyway, I consider 35 Hz the lowest frequency with most instruments that have somehow a fast attack. A huge organ, playing extremely low like 16Hz, produces slow notes with long duration. So even there, the advantage of perfect group delay, however you define the number, may be limited. Also, the recording will contain huge room influence.
 
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Group delay. If I decide to add some EQ to extend the in room response I would be concerned about power issues and potential excursion issues long before I would worry about the audibility of any added group delay from the EQ;

The EQ would be in the lowest ranges centered on the EQ frequency range and not at the crossover.

Rob :)
 
I am glad to see a thread which asks head on what you are willing to compromise first. My present compromise is having had put the wrong driver in the wrong box really. I tolerate it for now because I have chosen to until I find an answer that can deal with the bass bloat. Yah, I know, this is about sub woofers. Thing is, until I get the proper integration, the sub doesn't really sound right either. I realize that this at the very edge of the topic. Looking forward to hearing more from everyone.
 
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Hi,

What does compromise mean in this thought experiment, like when maxSPL is compromized for example, whats the level? pardon, having fun thinking about it, writing some chains of thought as it is a thought experiment :)

If maxSPL would go first to favor the other three. Question would be, can I still reach SPL I want it just comes with some distortion, right? so giving up maxSPL is actually just giving up on distortion?:) distortion would actually make it seemingly louder for what the SPL actually is, this would be good solution for some use cases, where sound quality isn't main focus in sense tha distortion is bad, right?

Ok lets try reverse, whats the most important feature on a subwoofer? I'd say most important feature of any sub would be the extension, to extend bandwidth to low enough. Nice, but what's low enough, and what SPL? Can I define low enough extension down to 10Hz? which would mean that nothing is actually compromized with 99% of music, because headroom at 30-40Hz would be plenty, with low group delay, right?:)

Ok, could I assume there is signal processor in the system? then I'd give up on group delay, because it can be manipulated with DSP, if FIR capability then no prnalty on the other parmeters. How would you actually change group delay of a sub whose box size and driver are already chosen? Do you mean that the box could be ported as well?

Well, its fun trying to think about the stuff, but cannot choose one without more constrains or details what need to go into it, context where it's targeted at. Add those and answer pops out. But to get good sound you want them all, you don't want compromize on sound. Then, real compromise would be size, and cost that comes with it, like complexity :)

Voted for distortion, because I imagine it will likely sound punchy and rocking nicely and seem worth the money, it still has max SPL capability and extension to get it to fun territory. It would sound clean with lower listening level, great for background music, without any compromize, right? :)
 
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@tmuikku
Getting more low end basically means higher distortion, this is even worse when you also want more SPL.
Therefor it is an option to choose :)
You can definitely make arguments that this parameter wouldn't be that important for lower frequencies, since our ears are not very sensitive to it.

What to compromise means, is totally depending how you look at things. ;)
I am mostly curious what people would pick and for what reason.
Yes it is an active system, so you can manipulate stuff if you want obviously.

FIR filters at those low frequencies can be expensive in DSP instructions though, so it it something to keep in mind.
In an active (sub) system, one could use HP filters or EQ to change the performance.
So, to squeeze out more SPL, one could use a 2nd order HP filter.
Obviously this will get less low-end and a worse group-delay in return.
 
With some DSP you can change parameters with signal level, so you can change your priorities with SPL. I have a notch on the left speaker from a bay window, so I fill it with the right speaker. At high levels, it can’t be done with the speakers I have, so when it’s loud, that frequency is lower than the rest, but nobody notices at parties
Brian
 
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There are so many facets for each of us individually. What, how much, which are totally at the listeners preference. Given stricter 'rules' of right and wrong in audio (and so many other things) still should be broken by preference.
When it comes to bass, nothing seems to impress like a clean low bass. I know, I know, pick ONE, leave one, but a few selected times in my life there was both.
 
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@tmuikku
Getting more low end basically means higher distortion, this is even worse when you also want more SPL.
Therefor it is an option to choose :)
You can definitely make arguments that this parameter wouldn't be that important for lower frequencies, since our ears are not very sensitive to it.

What to compromise means, is totally depending how you look at things. ;)
I am mostly curious what people would pick and for what reason.
Yes it is an active system, so you can manipulate stuff if you want obviously.

FIR filters at those low frequencies can be expensive in DSP instructions though, so it it something to keep in mind.
In an active (sub) system, one could use HP filters or EQ to change the performance.
So, to squeeze out more SPL, one could use a 2nd order HP filter.
Obviously this will get less low-end and a worse group-delay in return.
Could you put switch on the DSP to choose between presets? party mode that kicks more than normal mode that tries to keep it clean somehow. If you have box at hand with given performance, and can only do DSP to tweak the knee, one way or another, then tweak :) closed box, high pass filter, if the box doesn't get loud enough at party people would reach in the back of the box looking volume knob. If there was a turbo button that takes out stuff below 30-40Hz and gives slightly more headroom with cost in low extension ang group delay, I'd say it will get pushed and stay in. To really get more output you'd need to slice it higher up, which robs title from a sub. How much, few db? not gonna rock the house if it didn't before, so I'm not sure what you are after?

choosing a driver and size of the system you've selected what the performance is, slight tweaks won't do big difference I think, or do they? You can boost lows for 6db when there is plenty of headroom left. But can you do difference of doubling volume displacement for example, can you slice excursion in half with DSP for party tracks without losing the party? I'm using party meter, smile on the face, if the sub is big eough to have that then it is and tweak what ever, if it doesn't do it then I'm not sure any amount of DSP tricks do it? Or do they?
 
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