Agreed on 12" vs 21". There a lots of people that enjoy all kinds of EDM or pop music for parties.
And why not buy 2x Crown XLS amps? One for each channel in Y-mode so you can use LPF for the sub and HPF for the KEF. You can still use the KEF fullrange but with a HPF they don't have to do the heavy lifting. They don't have real DSP but they don't have much delay either.
And why not buy 2x Crown XLS amps? One for each channel in Y-mode so you can use LPF for the sub and HPF for the KEF. You can still use the KEF fullrange but with a HPF they don't have to do the heavy lifting. They don't have real DSP but they don't have much delay either.
I've found this driver.
https://www.bluearan.co.uk/index.ph..._21_inch_8_Ohm_Loudspeaker&id=BMA21QLEX1600FE
That's 8ohms. Although that may suit me better, not sure. Definitely not twice as cheap as the the PD unit. But do you think it is objectively better... or just better value?
https://www.bluearan.co.uk/index.ph..._21_inch_8_Ohm_Loudspeaker&id=BMA21QLEX1600FE
That's 8ohms. Although that may suit me better, not sure. Definitely not twice as cheap as the the PD unit. But do you think it is objectively better... or just better value?
I don't want to appear as an oracle telling the bad news. You can get excellent bass with DSP, but DSP today definitely degrades the midrange and tweeter section.
For much less money you can get better results with a passive/active analog crossover.
In a previous post I asked what level of sound quality is planned to get in the end not just for a simple reason
Sawing and assembling a couple of wooden boards and screwing a driver in there is not the biggest problem. It's just the top of the iceberg.
Not immediately visible, the underwater part of the iceberg is to choose the right crossover, properly integrate the sub into the room, and most importantly smoothly and seamlessly combine with the speakers, not only in the response, but also in phase and tonal balance.
For much less money you can get better results with a passive/active analog crossover.
In a previous post I asked what level of sound quality is planned to get in the end not just for a simple reason
Sawing and assembling a couple of wooden boards and screwing a driver in there is not the biggest problem. It's just the top of the iceberg.
Not immediately visible, the underwater part of the iceberg is to choose the right crossover, properly integrate the sub into the room, and most importantly smoothly and seamlessly combine with the speakers, not only in the response, but also in phase and tonal balance.
Funny, I owned a top-of-the-line DBX DriveRack VENU360 rather than an entry-level Driverack PA2 or Minidsp 2x4HD, built my own DSP on an AD21489 rather than a simple ADAU. I've listened to over 20... more like 30 setsups with a single sub, of a caliber starting at 12+. From simply expensive, to outrageously expensive under half a million euros, including Trinnov. And I came to an obvious conclusion - 90% of the speakers play separately, and the sub itself separately and only damage the whole impression of the music.
Guys, we are talking about the sub in relation to music playback, not home theater, right?
Yeah, you're absolutely right. Without measurements you'll only get just loud bass, but you'll never get smooth integration with the speakers
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Some notes:
- Removing the lead lining of the enclosure will reduce the overall mass dramatically. That might not be a good thing: the Mms on a 21" driver is of the order of 0.5kg. That's the sort of weight which can have a cabinet dancing around on a hard floor. It doesn't necessarily need to be lead, but I'd recommend making the cabinet as heavy as can sensibly be managed.
- Since this is for subwoofer use, standing waves within the cabinet aren't a concern.
- While a 21" subwoofer might be a lot of fun in a domestic environment, I'd seriously consider a few smaller subwoofers, spread around. If your room has a cancellation, no amount of output will rescue it. The multi-subwoofer approach has a much better chance of good sound.
- A HPF on the Kef speakers will certainly reduce distortion and free up some headroom in the upper-bass/lower-mid. If you'd like to keep it analogue there, it can be done with op-amps, or even just something passive at line-level, between the preamp and power amp.
- As always, measurements and EQ will be critical. In fact, with DSP already in place, I'd make the cabinet smaller, so long as Xmax can still be reached with the available power.
Chris
- Removing the lead lining of the enclosure will reduce the overall mass dramatically. That might not be a good thing: the Mms on a 21" driver is of the order of 0.5kg. That's the sort of weight which can have a cabinet dancing around on a hard floor. It doesn't necessarily need to be lead, but I'd recommend making the cabinet as heavy as can sensibly be managed.
- Since this is for subwoofer use, standing waves within the cabinet aren't a concern.
- While a 21" subwoofer might be a lot of fun in a domestic environment, I'd seriously consider a few smaller subwoofers, spread around. If your room has a cancellation, no amount of output will rescue it. The multi-subwoofer approach has a much better chance of good sound.
- A HPF on the Kef speakers will certainly reduce distortion and free up some headroom in the upper-bass/lower-mid. If you'd like to keep it analogue there, it can be done with op-amps, or even just something passive at line-level, between the preamp and power amp.
- As always, measurements and EQ will be critical. In fact, with DSP already in place, I'd make the cabinet smaller, so long as Xmax can still be reached with the available power.
Chris
you would not be OK with that resonance being 2 octaves away from the crossover and EQ'd?
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it's the best model from DBX.
I rented a LAKE LM26 processor from a friend for a couple of days. it doesn't sound any better than the DBX.
I rented a LAKE LM26 processor from a friend for a couple of days. it doesn't sound any better than the DBX.
@gaga_r
Good subwoofer integration with main speakers for stereo indeed is not easy but it should be doable isn't it? After all most stereo speakers also have woofers which can have passive or even active filters?
My journey with subs stretches over >25 years.
In my actual setup:
I have 4 huge subs across the room so they play gently.
All of them are sealed and passive/amplified without LPF.
All filtering, room correction and time alignment is done in my AVR (Denon AVC-A1H)
Result is that I don't hear any difference in the mids and highs going from direct (without subs) to normal operation (with RC up to 300Hz) where the main speakers are crossed at 100Hz. I only hear a more extension/authority in the lowest octaves with all music where classical can get frightening real.
BTW I have high expectations with the upcoming Dirac ART (Active Room Treatment) where bass is corrected up to 150Hz.
Good subwoofer integration with main speakers for stereo indeed is not easy but it should be doable isn't it? After all most stereo speakers also have woofers which can have passive or even active filters?
My journey with subs stretches over >25 years.
In my actual setup:
I have 4 huge subs across the room so they play gently.
All of them are sealed and passive/amplified without LPF.
All filtering, room correction and time alignment is done in my AVR (Denon AVC-A1H)
Result is that I don't hear any difference in the mids and highs going from direct (without subs) to normal operation (with RC up to 300Hz) where the main speakers are crossed at 100Hz. I only hear a more extension/authority in the lowest octaves with all music where classical can get frightening real.
BTW I have high expectations with the upcoming Dirac ART (Active Room Treatment) where bass is corrected up to 150Hz.
they have factory-made stitching. Most of them have or rent acoustic rooms.
It's not a trivial task to sew the bands together correctly and harmoniously.
and stitching a sub and a woofer together is even more difficult.
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I am a huge fan of Beyma drivers and have used many different ones over the years, but not a 21" I would probably challenge anybody to hear the difference between any of the pro 21" units on the market, and I could not identify the RCF compared with Blue Arran's budget 'JAM Systems' 21" (made in Eastern Europe)- I have two of each. If you are anywhere near North Devon you would be welcome to pop in and have a look at them.
Controllers - I used BSS in my PA times, still have a Minidrive around for my small PA (6x18" reflex, 2x12" & 2"/1" Coax). Prefered them over the DBX units but the Venue360 looks like a serious tool. You still loose 20dB of this nice S/N as soon you connect standard HiFi components with HiFi levels ... that's why I remembered sound staging.
With a modern DSP solution you get the S/N of the controller for the whole chain. (Hypex plate amp - 115dB S/N) With more effort you can push that to 123-125dB S/N (not sure if that's really needed - but it's fun to achieve the best possible ;-) The upper measurement is at the power amp on 4,4R and 270W)
These sound transparent and clear and smooth without any digital artefacts - cause these are so low you can't hear them even with high sensitive speakers. Even digital volume control comes with no audible artefacts - that's the benefit of such a system, you can prozess in the digital domain and artefacts are below acoustical noise floor (ear or room).
One sub - it's important to check the perfect position of this sub! That's at least half of the job. And it never was where I put it first or where it would look nice 🤓. In my strongly dampened listening room it is actually in the corner, membrane close to the side wall. Didn't expect that ... but works best in there. My office totally different, couldn't realise the best spot so have to live with 2nd best. In both rooms you can't hear that a subwoofer is playing until you switch it of. Only for music.
When you get your level right (=low, I prefer 3-5dB rise to low frequencies but not more), phase right and crossover right (when your woofer plays louder you often need to pull the corner frequencies appart) and don't have a "one note woofer" (high Q resonance woofer) - this works perfect.
With a modern DSP solution you get the S/N of the controller for the whole chain. (Hypex plate amp - 115dB S/N) With more effort you can push that to 123-125dB S/N (not sure if that's really needed - but it's fun to achieve the best possible ;-) The upper measurement is at the power amp on 4,4R and 270W)
These sound transparent and clear and smooth without any digital artefacts - cause these are so low you can't hear them even with high sensitive speakers. Even digital volume control comes with no audible artefacts - that's the benefit of such a system, you can prozess in the digital domain and artefacts are below acoustical noise floor (ear or room).
One sub - it's important to check the perfect position of this sub! That's at least half of the job. And it never was where I put it first or where it would look nice 🤓. In my strongly dampened listening room it is actually in the corner, membrane close to the side wall. Didn't expect that ... but works best in there. My office totally different, couldn't realise the best spot so have to live with 2nd best. In both rooms you can't hear that a subwoofer is playing until you switch it of. Only for music.
When you get your level right (=low, I prefer 3-5dB rise to low frequencies but not more), phase right and crossover right (when your woofer plays louder you often need to pull the corner frequencies appart) and don't have a "one note woofer" (high Q resonance woofer) - this works perfect.
I prefer to make the housing STIFF and not heavier as needed for pure subwoofer use. When you need more weight get some stone/concrete plates and put it on the woofer. Also helps with decoupling when useing Sylomer or similar.
I also would strongly prefer a few 10-12" instead of one 21". Just a singele bass array gives already such a benefit over one sub.
Close reflex ports if there are some and add a small capacitor between preamp and power amp (filter 1st order - together with the speaker filter 3rd order). Value also depends on the input resistance of the power amp - do some nearfield measurements of your lf driver to check that.
Yup, don't overestimate the influence of Q of a closed speaker when you listen in a room ...
you can't push
i just wanted to say if you have proper whole system with good DAC (in my case Mytek) you can achieve the best result with active/passive analog cross than any DSP. Because
any best modern DSP unfortunately can't achieve 123-125 db.
second, DSP do double convertion ADC/DAC, which, of course, doesn't enhance the sound .
third, any modern DSP dont have on the board best internal DAC chip, as like a ESS9038Pro/AK4499
absolutely right 👍
but in practice it's not as easy to do as say 🙂 😉
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