Sreten,
right, I forgot about that, since the digital signal is wideband, a 0 dBFS treble signal would have to be something like a single cymbal without any low frequencies.
Charles,
that could work, though in my system I tried it and some of the PSU modulation by the demands of the bass did filter through to the mid and treble amps. I wouldn't have noticed if I had not hooked it up experimentally once with long lines and questionable ground routing. Under these conditions there was a severe resonance and boomy mids (sounded spectacular... but not real).
Basically if you use the same PSU for all bands you forgo part of the advantage of multi amping. I think separate PSUs for the separate bands are far more important than separate PSUs for left and right channels (the stereo source having already a lot of common signals, so that any low level L-R crosstalk likely matters little. not to speak of the in room mixing).
right, I forgot about that, since the digital signal is wideband, a 0 dBFS treble signal would have to be something like a single cymbal without any low frequencies.
Charles,
that could work, though in my system I tried it and some of the PSU modulation by the demands of the bass did filter through to the mid and treble amps. I wouldn't have noticed if I had not hooked it up experimentally once with long lines and questionable ground routing. Under these conditions there was a severe resonance and boomy mids (sounded spectacular... but not real).
Basically if you use the same PSU for all bands you forgo part of the advantage of multi amping. I think separate PSUs for the separate bands are far more important than separate PSUs for left and right channels (the stereo source having already a lot of common signals, so that any low level L-R crosstalk likely matters little. not to speak of the in room mixing).
I know that seperate PSUs would be better (depending on PSR) but at some point you will end up with a huge PSU.
This does not matter much if you use separate amps, but if you want to integrate the electronics into the speaker it can get a PITA.
Regards
Charles
This does not matter much if you use separate amps, but if you want to integrate the electronics into the speaker it can get a PITA.
Regards
Charles
phase_accurate said:
Well IMO RC filtering the main (unregulated) supply has
some advantages, but like I said I wouldn't take it too far.
🙂 sreten.
Power specs for a "high end" tweeter, the Seas Millennium:
SHORT TERM MAXIMUM POWER* 200 W
LONG TERM MAXIMUM POWER* 90 W
CHARACTERISTIC SENSITIVITY (1W,1m) 88 dB SPL
OPERATING POWER ( 96 dB SPL , 1m) 6.3 W
* IEC 268-5, VIA HIGH PASS BUTTERWORTH FILTER: 2500 Hz 12 dB/oct.
SHORT TERM MAXIMUM POWER* 200 W
LONG TERM MAXIMUM POWER* 90 W
CHARACTERISTIC SENSITIVITY (1W,1m) 88 dB SPL
OPERATING POWER ( 96 dB SPL , 1m) 6.3 W
* IEC 268-5, VIA HIGH PASS BUTTERWORTH FILTER: 2500 Hz 12 dB/oct.
MBK
I’m interested that you’ve narrowed it down to horns and dipoles. I’ve been having debating with someone about these two. I won't say (just yet) which I generally lean to. 😉
Which do you favour, and/ or for which parts of the audio spectrum/ in which situation?
Cheers
RG
I’m interested that you’ve narrowed it down to horns and dipoles. I’ve been having debating with someone about these two. I won't say (just yet) which I generally lean to. 😉
Which do you favour, and/ or for which parts of the audio spectrum/ in which situation?
Cheers
RG
RG,
so far I have "only" been experimenting with dipoles. I liked the clean bass I was getting (narrowed dispersion -> less room effects, better power balance to the mids). So I stayed with it.
I learned most of what I know about speaker trade offs from this ongoing dipole building experience and much of the theory came from Siegfried Linkwitz's site. So far over a couple of years I experienced almost all the trade offs SL is debating and every time I do something he didn't advise, I come back to his recommendations... clearly, he knows what he's talking about. I still ignore some of it - I use a Diatone driver fullrange up from 300 Hz, which I am just now complementing with a dome tweeter. From calculations it follows that my setup is borderline for dynamics and dispersion (excursion limits of the small driver, limited dispersion at the high end). But I like my system because it sounds very natural. I have heard the Orions, they are more detailed and more effortless than my setup. For some reason though both me and my wife preferred the balance of my current setup. Maybe it's just that we got used to it. Anyway, for now I work on my system's limitations while keeping its qualities. For anybody who starts from scratch I can only recommend the Orions, it's going to take you years to get to the same level of finesse. If you're lucky.
Horns: the one big, big trade off of dipoles is in the excursion demands for the bass (where they are most useful). I have yet to hear a true deep bass horn, but from what I know of upper register horns, you should be able to beat a dipole on grounds of resolution and dynamics. But then the horn would be huge. So, here we have the trade off of horns. I think all things considered a dipole system is the way to go, if necessary double up the woofers to no end, it's still going to be easier and smaller than a bass horn.
For mid and treble, horn systems usually have that sweet spot and imaging problem. I don't get that feeling of space that I get from dipoles, more like a microscope, or headphones. I'd like to experiment with a unity horn though, where the dispersion issue seems to be better resolved, but tech data are scarce for DIY'ers. And it's $$$.
so far I have "only" been experimenting with dipoles. I liked the clean bass I was getting (narrowed dispersion -> less room effects, better power balance to the mids). So I stayed with it.
I learned most of what I know about speaker trade offs from this ongoing dipole building experience and much of the theory came from Siegfried Linkwitz's site. So far over a couple of years I experienced almost all the trade offs SL is debating and every time I do something he didn't advise, I come back to his recommendations... clearly, he knows what he's talking about. I still ignore some of it - I use a Diatone driver fullrange up from 300 Hz, which I am just now complementing with a dome tweeter. From calculations it follows that my setup is borderline for dynamics and dispersion (excursion limits of the small driver, limited dispersion at the high end). But I like my system because it sounds very natural. I have heard the Orions, they are more detailed and more effortless than my setup. For some reason though both me and my wife preferred the balance of my current setup. Maybe it's just that we got used to it. Anyway, for now I work on my system's limitations while keeping its qualities. For anybody who starts from scratch I can only recommend the Orions, it's going to take you years to get to the same level of finesse. If you're lucky.
Horns: the one big, big trade off of dipoles is in the excursion demands for the bass (where they are most useful). I have yet to hear a true deep bass horn, but from what I know of upper register horns, you should be able to beat a dipole on grounds of resolution and dynamics. But then the horn would be huge. So, here we have the trade off of horns. I think all things considered a dipole system is the way to go, if necessary double up the woofers to no end, it's still going to be easier and smaller than a bass horn.
For mid and treble, horn systems usually have that sweet spot and imaging problem. I don't get that feeling of space that I get from dipoles, more like a microscope, or headphones. I'd like to experiment with a unity horn though, where the dispersion issue seems to be better resolved, but tech data are scarce for DIY'ers. And it's $$$.
MBK
Thanks, I was thinking that way too.
I am intending to build the Phoenix (higher capability, got a good deal on the mid drivers), but was also going to an active 3 way with G ribbon tweeter, PHL mids + either
dipole or - for a claimed 6 dB more efficiency - cardiod bass (a la http://www.geocities.com/kreskovs/NaO-Woofer1.html )
Thanks for the severity of the warning “it's going to take you years to get to the same level of finesse. If you're lucky.”
I suspected it would be tough – but I’ll probably still try.
Cheers
Thanks, I was thinking that way too.
I am intending to build the Phoenix (higher capability, got a good deal on the mid drivers), but was also going to an active 3 way with G ribbon tweeter, PHL mids + either
dipole or - for a claimed 6 dB more efficiency - cardiod bass (a la http://www.geocities.com/kreskovs/NaO-Woofer1.html )
Thanks for the severity of the warning “it's going to take you years to get to the same level of finesse. If you're lucky.”
I suspected it would be tough – but I’ll probably still try.
Cheers
RG,
Good, welcome to the club, misery seeks company 😉
Seriously though, interesting concepts you are trying, and the balance and trade offs will be different, just as it is with my Diatone+double 10" woofer dipoles. In fact I do use a folded back baffle (U-shape). I had noticed before that the nulls in my system are not very noticeable, and that the bass was cleaner than from a box, but could still get boomy at certain frequencies. Then I read about the cardioid concept and realized that my radiation pattern likely goes towards the cardioid.
The difference to a true dipole you can expect, from my limited comparison with the Orion, is that the room interaction will be stronger with the cardioid (in a noticeable way), so you have to take care to equalize room resonances out. I initially skipped that step, and when I finally did it, the midrange cleaned up remarkably. On the bright side, the cardioid will likely sound a bit more impactful and warm than a pure dipole bass which is, err, hate that overused cliche word, very "analytical". Maybe that's why my speakers feel "natural".
But, be careful, again Linkwitz gives very good recommendations on drivers, and I did notice how the Orion's drivers were noticeably more detailed than mine - in other words, less IMD, less THD, less energy storage... ah well...
Oh yeah, another thing: with a bass U-baffle, your 1/4 wave resonance will be lower than with an H-frame, therefore harder to EQ and closer to your X-O points where you don't want it. Trade offs, trade offs...
Good, welcome to the club, misery seeks company 😉
Seriously though, interesting concepts you are trying, and the balance and trade offs will be different, just as it is with my Diatone+double 10" woofer dipoles. In fact I do use a folded back baffle (U-shape). I had noticed before that the nulls in my system are not very noticeable, and that the bass was cleaner than from a box, but could still get boomy at certain frequencies. Then I read about the cardioid concept and realized that my radiation pattern likely goes towards the cardioid.
The difference to a true dipole you can expect, from my limited comparison with the Orion, is that the room interaction will be stronger with the cardioid (in a noticeable way), so you have to take care to equalize room resonances out. I initially skipped that step, and when I finally did it, the midrange cleaned up remarkably. On the bright side, the cardioid will likely sound a bit more impactful and warm than a pure dipole bass which is, err, hate that overused cliche word, very "analytical". Maybe that's why my speakers feel "natural".
But, be careful, again Linkwitz gives very good recommendations on drivers, and I did notice how the Orion's drivers were noticeably more detailed than mine - in other words, less IMD, less THD, less energy storage... ah well...
Oh yeah, another thing: with a bass U-baffle, your 1/4 wave resonance will be lower than with an H-frame, therefore harder to EQ and closer to your X-O points where you don't want it. Trade offs, trade offs...
MBK
You’ve done some interesting experiments. Actually I was thinking of initially building one H baffle and one U baffle, and having a play.
It will be good when U baffles and baffle shapes generally get trialled and modelled more.
😉
You’ve done some interesting experiments. Actually I was thinking of initially building one H baffle and one U baffle, and having a play.
It will be good when U baffles and baffle shapes generally get trialled and modelled more.
😉
I haven't posted here in a while, but anyway...
I've built an active 3 way system. I'd like to think it's on the way towards high end 🙂
The drivers are Shivas till 110hz, pair of Focal 7NV4211 midbasses 110-2400hz, Focal TC120tdx2 tweeter 2400+.
It's a MTM standmount with the Shivas in big ported sonosubs standing behind the mains.
Crossover is 24dB/octave Linkwitz Riley.
Amps are 300+watts for the Shivas, 180w or so in the midbasses (110w into 8ohms), and 50 watts into the tweeter.
The limiting factor SPL wise, is bottoming out the Shivas - at thats at a stupidly loud level
The system is extremely DYNAMIC and clean. The room is medium sized.
50 watts is plenty for a tweeter, if it's reasonably efficient.
100 watts is plenty for a midbass pair, if they're reasonably efficient.
300 watts is enough to bottom the shiva before clipping, but that depends on your enclosure.
Stop debating, and start building. The only thing I would contemplate doing differently now, is that it might be a dipole system if I did it again...
I've built an active 3 way system. I'd like to think it's on the way towards high end 🙂
The drivers are Shivas till 110hz, pair of Focal 7NV4211 midbasses 110-2400hz, Focal TC120tdx2 tweeter 2400+.
It's a MTM standmount with the Shivas in big ported sonosubs standing behind the mains.
Crossover is 24dB/octave Linkwitz Riley.
Amps are 300+watts for the Shivas, 180w or so in the midbasses (110w into 8ohms), and 50 watts into the tweeter.
The limiting factor SPL wise, is bottoming out the Shivas - at thats at a stupidly loud level
The system is extremely DYNAMIC and clean. The room is medium sized.
50 watts is plenty for a tweeter, if it's reasonably efficient.
100 watts is plenty for a midbass pair, if they're reasonably efficient.
300 watts is enough to bottom the shiva before clipping, but that depends on your enclosure.
Stop debating, and start building. The only thing I would contemplate doing differently now, is that it might be a dipole system if I did it again...
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