For me, the issue becomes more about the resonant frequencies in my room and the general profile of the bass. My room is almost exactly 1/2 the 30 Hz wavelength, so my bass response has a peak at 30 Hz. If I turn the bass up, 30 Hz will dominate. At a certain point (and source material dependent) this becomes annoying, even if other factors are fine.
I suppose my question is why though, if it is just a design philosophy or opinion I understand, no argument, but I would be interested.
Eq, how you do it, also got disadvantages. With DSP it means that you need to digitise the signal, which many objects when they use analog sources (like vinyl).
With an passive system, the phase of the driver is affected and often you loose some sensivity. Which in the case of the use of a low power amp (SET or class A) means you loose volume.
The least intrusive way of doing it is with an active analog eq, but there the phase is also affected (but often in a lesser degree than passive). For me it's also a last resort solution.
But most of my systems don't have an eq build in (or not a good eq, so it's bypassed). I prefer to choose the right driver in the right cabinet so i have the bass response i need in stead of band aid.
With an passive system, the phase of the driver is affected and often you loose some sensivity. Which in the case of the use of a low power amp (SET or class A) means you loose volume.
The least intrusive way of doing it is with an active analog eq, but there the phase is also affected (but often in a lesser degree than passive). For me it's also a last resort solution.
But most of my systems don't have an eq build in (or not a good eq, so it's bypassed). I prefer to choose the right driver in the right cabinet so i have the bass response i need in stead of band aid.
Thanks. How does the phase effect of active analogue eq compare to that of a MLTL?
Have you heard EQ'd full range drivers in sealed boxes and didn't like the sound?
Have you heard EQ'd full range drivers in sealed boxes and didn't like the sound?
I use DEQ on mine to fill out from 100Hz down to 50Hz on my sealed boxes. Sounds nice at low volumes and wife proof when she invites her friends round for some karaoke
Brian
Brian
I used to use a lot of bass EQ, up to 14 dB on my arrays containing 25 drivers/side. After adding a pair of subwoofers it has been reduced to 5 dB. All 25 drivers share that load.
It worked excellent with that level of bass boost and I most certainly don't see EQ as a last resort or band aid, but a necessary tool for arrays to shape the frequency response. Just like passive components or even box shape and size can alter the response of drivers. Today I have a combination of passive filters and digital EQ, to fine tune line array behavior.
That said, I would be a lot more conservative with single drivers and would rather add helper woofers in such a case. But even on my subwoofers I do use bass EQ in the same jest as a Linkwitz transform. As long as the dynamic range that is wanted fits within the limits of what the system brings.
Every single piece of music I listen to has been altered with plenty of EQ to bring out the creator's vision.
My applied EQ is there to do that composition justice, get it as close as I can to what was intended originally. Give or take a few personal preference tweaks (like level of bass).
It worked excellent with that level of bass boost and I most certainly don't see EQ as a last resort or band aid, but a necessary tool for arrays to shape the frequency response. Just like passive components or even box shape and size can alter the response of drivers. Today I have a combination of passive filters and digital EQ, to fine tune line array behavior.
That said, I would be a lot more conservative with single drivers and would rather add helper woofers in such a case. But even on my subwoofers I do use bass EQ in the same jest as a Linkwitz transform. As long as the dynamic range that is wanted fits within the limits of what the system brings.
Every single piece of music I listen to has been altered with plenty of EQ to bring out the creator's vision.
My applied EQ is there to do that composition justice, get it as close as I can to what was intended originally. Give or take a few personal preference tweaks (like level of bass).
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True. Although that's within the context of a wideband driver based array, which is a somewhat different scenario in that you go in from the outset with EQ as an integral part of the design, and with well-chosen drivers they have sufficient power-handling for this to be practical in many cases. With a smaller number of drivers, or one unit, the limitations of equalising the LF response are likely to kick in significantly earlier. I'm not knocking it (far from it in the case of arrays), just noting once again for the OP that context is critical.
Do you think you heard any IMD/AMD/FMD/PMD (I include "phase modulation distortion" because of this interesting article by Rod Elliott Doppler Distortion in loudspeakers) due to the increased excursion, although spread over 25 drivers I imagine that was quite minimal?
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Yes, that's what I'm particularly interested in, people's experience of the limitations and how they manifest themselves.
I use very much bass boost of up to 12db if possible to make the speaker linear down to 30/35 Hertz.
There is no technical problem with this as long:
- you use your loudspeaker for Hifi and not for public adress (although RCF does some frequency compensation of bass reflex designs in commercial products)
- you do not listen to low bass music very loud
I guess that frequency compensation of fullrange loudspeakers in too small boxes can even have some electrical advantage - in contrary to the telling that low bass amplification will kill the drivers (as long as you do not exceed xmax)
I wrote on this topic here:
Just wanted to show off my new 18in build
There is no technical problem with this as long:
- you use your loudspeaker for Hifi and not for public adress (although RCF does some frequency compensation of bass reflex designs in commercial products)
- you do not listen to low bass music very loud
I guess that frequency compensation of fullrange loudspeakers in too small boxes can even have some electrical advantage - in contrary to the telling that low bass amplification will kill the drivers (as long as you do not exceed xmax)
I wrote on this topic here:
Just wanted to show off my new 18in build
That based on lots of experience.
You should make things as good as possible then bandaid with EQ if needed.
Many typical rooms can benefit from something like DIRAC which can help deal with the problems of LF resonances in a room.
I started by designing and building a room that works really well. Most don’t have that luxury.
FALL Listening Space - diyAudio
dave
Have you experience of listening to EQ'd speakers in a closed box, for example, if so, was there anything wrong with the sound?
Yes. How loud you can play starts to be a limit, a compromise.
And with the smallish drivers i prefer one can get there quick.
dave
And with the smallish drivers i prefer one can get there quick.
dave
it is a balance.
Cone size, listening volume levels, distance to speaker, speaker on wall/floor/corner, type music, etc.
So eq levels are up to you, but the more bass boost, the quicker you get the voices gargling...………….
Cone size, listening volume levels, distance to speaker, speaker on wall/floor/corner, type music, etc.
So eq levels are up to you, but the more bass boost, the quicker you get the voices gargling...………….
Visaton FRS 8M in sealed Ikea salad bowls, and 9dB at 55Hz, room peak at 50Hz fills in the last bit. I live in an apartment, so can’t have high SPL without annoying the neighbours, so it suits us just fine. DEQ and limiting on the amp means that you can turn it up surprisingly loud without anything sounding nasty, even if it is a bit thin when loud
Brian
No such problems with the 25 drivers/side. I did not experience a big sound quality change when adding the subwoofer and relieving the arrays of their bass duties. Together those 25 little drivers have the surface area of a 15" woofer. Though still limited by the x-max restrictions of 2.55 mm of the single driver.
Producing bass is about moving air, so even an array like that will run into trouble if you're asking it to do loud low bass (like found in Home Theatre).
A single small driver wil get into trouble quite fast. Saver to get a helper woofer that can move that air.