Hi,
For multi sub setup based on Earl's method the phase of sub is a variable, in the sense that the polarity of sub could be inverted if needed.
However I am trying an approach where all the subs are in phase and use Eq only to blend them to produce a smooth response at listening position.
The Eq could be a parametric equaliser like this one Parametric and Sub-Woofer Equaliser in the intended sub range of 25Hz to 180Hz.
How many parametric bands are needed at the minimum?
Thanks and Regards,
WA
For multi sub setup based on Earl's method the phase of sub is a variable, in the sense that the polarity of sub could be inverted if needed.
However I am trying an approach where all the subs are in phase and use Eq only to blend them to produce a smooth response at listening position.
The Eq could be a parametric equaliser like this one Parametric and Sub-Woofer Equaliser in the intended sub range of 25Hz to 180Hz.
How many parametric bands are needed at the minimum?
Thanks and Regards,
WA
It depends on the room.
Just one or two parametric equalization filters helps a lot, though if ten are available, why not use them all.
Today it makes more sense to implement the parametric equalization in a DSP rather than an analog circuit.
Just one or two parametric equalization filters helps a lot, though if ten are available, why not use them all.
Today it makes more sense to implement the parametric equalization in a DSP rather than an analog circuit.
Agreed. Definitely one for DSP.
If you're struggling for filters, though, I'd say 2-3 as a minimum. With my current system and room, I can do the broad strokes with two filters below 100Hz.
However, parametric EQs are just bell curves, and those don't match the lumps & bumps of the room particularly well. With a few of them together, though, you can get pretty much any shape you want.
Chris
If you're struggling for filters, though, I'd say 2-3 as a minimum. With my current system and room, I can do the broad strokes with two filters below 100Hz.
However, parametric EQs are just bell curves, and those don't match the lumps & bumps of the room particularly well. With a few of them together, though, you can get pretty much any shape you want.
Chris
I thought the whole point of multsub was it reduced the need for EQ?
Rod's design I would say gives you enough to work on. The more channels you have the more you will drive yourself mad trying to chase the impossible!
Rod's design I would say gives you enough to work on. The more channels you have the more you will drive yourself mad trying to chase the impossible!
How quaint. Nostalgia trip. Elliott is great but today you'd simply buy the all-singing-all-dancing goddess, the Behringer DSP DCX2496. Why would any serious audiophile be without one?
B.
B.
1. the sub response can be linearized but should be already by construction.
2. the room standing waves have better to be tackled by positioning and low frequency absorbers. It is not possible "to fill in dips" of this kind. Boosts can be attenuated, usually only 2 in this range
3. Interference between the subs use low <80Hz xover
2. the room standing waves have better to be tackled by positioning and low frequency absorbers. It is not possible "to fill in dips" of this kind. Boosts can be attenuated, usually only 2 in this range
3. Interference between the subs use low <80Hz xover
Well, since you asked...
- No FIR
- Wrong signal levels for most home HiFi gear
- The limiters aren't great
- Limited processing - it runs out of DSP power if you try to do a few crossovers and some EQ on every output.
They're pretty useful, and cheap, but better products are available.
If you're curious about what sort of processing that's on offer in the Pro Audio world, download Amonia+ from Powersoft and have a play around.
Chris
Having access to equalization is almost free today. The point of multisub is to have less variation of the frequency response as measured across different seating positions.
Of course general efficiency must be good and there must be no dips in the frequency response, but those problems are not specific to multisub.
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I have a minidsp 2x4HD with one sub. I dont implement PEQ, because at the main listening position (right hand side of sofa) I have a null at 30Hz, and at my second listening position - (left hand side of the sofa - only 2 meters away), I have a peak at 30Hz. The difference is 15/20dB, so PEQ is pointless, because Ii will make things worse switching listening positions. Unless I use the 4 slots in the minidsp and switch with remote to suit listening position, which I cant be bothered with plus 20dB of PEQ should I boost uses up 99% of the power.
Multi subs is the way to go, and spend more time positioning them / phase aligning. IMO, having the ability to set delays to phase align each of your subs independently would be way more useful than PEQ.
Multi subs is the way to go, and spend more time positioning them / phase aligning. IMO, having the ability to set delays to phase align each of your subs independently would be way more useful than PEQ.
Yes, but because you can doesn't mean you should. You can easily do stupid things and make things worse or damaged (I am sure no one would admit to trying to kill a 20dB null with moar powa until something complained and died).
And some people want a simple box with 3 or 4 knobs on, not the disco lights of a behringer or having a laptop dedicated to EQ duty. Somewhere between nothing and total overkill is a solution for everyone. At what point diminishing returns kicks in is of course equally variable.
I set up three subs with 4 PEQs each and time alignment using a processor and REW I then went back to analogue out and used the settings in a mini dsp HD I am flat across a 2m seating area from 16-70 Hz The good thing about limited EQs is you have to think carefully about what you are cutting and where
That needs to be corrected to read "... to a mic, the FR is pretty flat at my chair", because to human hearing, the perceived tone is influenced by the characteristics of all the sound and timing that reaches the person.
If there is any careful listener who ever finished an REW EQ and then didn't have to tweak the tone?
Toole's spinorama evaluation tries to side-step that correction by endorsing speakers with dispersion that in typical rooms is helpful.
B.
You just changed my life. And completed the ambiguous doubts lingering in the folded corners of my harmonic bass pipe dream. Amen.
All half jokes aside, the main idea isnt half a joke, its real IMhO no mic and no listener ever coulda woulda found the same REW results and if the mic was the human ear(s) and their distance between, too and from everything including themselves... whole not-her reality in majority of the applications and ideas people individually might use for their own setups and designs(myself included no doubt or hesistation in not doubting... its all sweeps, but not in our heads...
But, please choose a few ways to narrow down the priiorities of somethings more than others and ??? Cant, its Impossible, pick whatever is learned and always changing in that ongoing cycle, or find a special place and likeminded people with similar ears... cause otherwise its all true and nobody is wrong, and theres no answers for anyone 🙁
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The reason I didn't say people differ is because Toole says trained observers* agree more than differ, hearing defects aside**.
It is the room interacting with the speaker and the audible result at the listener's chair (including reverb time sorted by frequency) that is "the sound" which humans hear. I am not bringing in individual differences.
Starting off with REW is a very very good idea.
B.
* which doesn't mean all experienced listeners, only those trained to his style of observation
** you can also have variation if you use a soft-sound tube amp or play a lot of 78's or most of the recordings are over-processed pop music or if you always play loud or soft
It is the room interacting with the speaker and the audible result at the listener's chair (including reverb time sorted by frequency) that is "the sound" which humans hear. I am not bringing in individual differences.
Starting off with REW is a very very good idea.
B.
* which doesn't mean all experienced listeners, only those trained to his style of observation
** you can also have variation if you use a soft-sound tube amp or play a lot of 78's or most of the recordings are over-processed pop music or if you always play loud or soft
I set my subwoofers up using REW and a mini dsp you need to think of an seating area and not a single seat you then adjust the overall response I preferred a 4 dB lift below 80 HZ I didn’t EQ above 100 HZ and measured individual curves and blended by ear knowing how they overlapped. This is just SPL across a frequency range and says nothing about sound quality as we know
The note was the subs were flat not the whole curve. We hear in a room and factor that in I understand that