So there's no way?
I thought that that was the idea with multiple drivers, to get 6+bD increase and lower Xmax at low frequencies? Also isn't that one of the reasons for a TQWT variant with a tapered port?
COuld I ad two drivers together and then lower the high freq. from the driver to to match the low frq part? ie. make it flat with a crossover?
David
I thought that that was the idea with multiple drivers, to get 6+bD increase and lower Xmax at low frequencies? Also isn't that one of the reasons for a TQWT variant with a tapered port?
COuld I ad two drivers together and then lower the high freq. from the driver to to match the low frq part? ie. make it flat with a crossover?
David
Re: So there's no way?
You get 3-6 dB increase (in theory) and when used as bafflestep compo it really means you don't have to shelve down the mid/HF 3-6 dB.
Tapered port?
You could -- the shelving circuit as above -- but i prefer not to use the extra inductor & resistor in the signal path.
dave
EternaLightWith said:
You get 3-6 dB increase (in theory) and when used as bafflestep compo it really means you don't have to shelve down the mid/HF 3-6 dB.
Tapered port?
You could -- the shelving circuit as above -- but i prefer not to use the extra inductor & resistor in the signal path.
dave
tapered, you know...
Open at one end versus closed. Stuffed port versus a true TL.
I was reading that even though TL and their derivatives? TQQT? are not like a ported enclosure, you can use the port be resonant at certain freq. That's what I was referring to.
David
Open at one end versus closed. Stuffed port versus a true TL.
I was reading that even though TL and their derivatives? TQQT? are not like a ported enclosure, you can use the port be resonant at certain freq. That's what I was referring to.
David
Re: tapered, you know...
I still don't quite get it. An aperiodic port, or a port in mass-loaded TQWT or TL?
EternaLightWith said:
I still don't quite get it. An aperiodic port, or a port in mass-loaded TQWT or TL?
Well considering I'm clueless about TL's
Well according to Bob's speaker page, there are four varieties of pipes. Since I I don't know what would be the best configuration for my case. I just put it all together with a general sweeping statement. Sorry for the confusion.
I'm disregarding Voigt pipes as I hear that they introduce an exaggerated null at F7.
I guess the choices are conventional TL, ML TQWT, and a Weems pipe.
The reason for the statement I made a couple of posts ago was in regards to the statement made by Bob on his webpage.
Perhaps I misunderstood his meaning.
Yet, if one were to use this approach, wouldn't you run into time smeared bass (ie. loose) ; the same problem that people complain about with ported enclosures?
David
Well according to Bob's speaker page, there are four varieties of pipes. Since I I don't know what would be the best configuration for my case. I just put it all together with a general sweeping statement. Sorry for the confusion.
I'm disregarding Voigt pipes as I hear that they introduce an exaggerated null at F7.
I guess the choices are conventional TL, ML TQWT, and a Weems pipe.
The reason for the statement I made a couple of posts ago was in regards to the statement made by Bob on his webpage.
Perhaps I misunderstood his meaning.
Yet, if one were to use this approach, wouldn't you run into time smeared bass (ie. loose) ; the same problem that people complain about with ported enclosures?
David
Each kind of line has an application with some driver somewhere. The classical TQWT is probably one of the hardest to find a driver for.
Martin has just released the 1st (i hop he expands on them) of his alignment tables... a quick way to get a good idea of a design for any open ended pipe.
http://www.quarter-wave.com/
dave
Martin has just released the 1st (i hop he expands on them) of his alignment tables... a quick way to get a good idea of a design for any open ended pipe.
http://www.quarter-wave.com/
dave
Maybe the Seas Excel M15 CH 001 could be an exotic alternative?
http://www.seas.no/excel_line/excel/E0016.PDF
http://www.seas.no/excel_line/excel/E0016.PDF
Grrr
The lack of FR plot for PHL are frustrating. ANy way I can extrapolate the FR extremes using their published data?
Like isn't reference effeciency usually at 1kH?
What about usuable freq. range? How to they come up with the range? Like what is it in relation to?
ie. FR meaning 80Hz to 4kHz for the 2440
David
The lack of FR plot for PHL are frustrating. ANy way I can extrapolate the FR extremes using their published data?
Like isn't reference effeciency usually at 1kH?
What about usuable freq. range? How to they come up with the range? Like what is it in relation to?
ie. FR meaning 80Hz to 4kHz for the 2440
David
this is a lot of work.
spent the last couple days figuring out ML's spreadsheets for MathCAD.
Have three data sheets and graphs for the following, Fostex208ez, PHL2420, PHL2520.
You guys want to take a look at them. Tell me if I'm even doing this right?
Which graphs do you need? Tell me and I'll post them first thing tomorrow.
Night all
David
spent the last couple days figuring out ML's spreadsheets for MathCAD.
Have three data sheets and graphs for the following, Fostex208ez, PHL2420, PHL2520.
You guys want to take a look at them. Tell me if I'm even doing this right?
Which graphs do you need? Tell me and I'll post them first thing tomorrow.
Night all
David
Does it really say your line is 9 inches long?
The 1st 3 graphs are the ones typically used when tuning, but they are all very illustrative.
dave
The 1st 3 graphs are the ones typically used when tuning, but they are all very illustrative.
dave
Looks like you are tuning to almost an octave higher than the Fs. (that is what the peak in the 1st chart shows)
dave
dave
Is that bad?
Yeah, I figured take a 1 dB hit in the 200Hz to 300 Hz range to make it roll off around 100 Hz and still hit a good 94dB at 80Hz.
Then roll off fast. Looks like 24dB slope... I think
Yup, all 9 inches. Is that ridiculously short? I wouldn't know
The PHL2440 the other hand is... uhh... 4inches long with a 1.5'' port width and length.
It is maybe It's almost identical to the fostex fe-208es
On the other hand, the PHL 2520 has a higher SPL rating throughout but rolls off about 5dB lower at 80 Hz.
ie. 90dB at 80Hz instead of 95dB (Fostex FE-208es)
So what does all this mean?
David
Yeah, I figured take a 1 dB hit in the 200Hz to 300 Hz range to make it roll off around 100 Hz and still hit a good 94dB at 80Hz.
Then roll off fast. Looks like 24dB slope... I think
Yup, all 9 inches. Is that ridiculously short? I wouldn't know
The PHL2440 the other hand is... uhh... 4inches long with a 1.5'' port width and length.
It is maybe It's almost identical to the fostex fe-208es
On the other hand, the PHL 2520 has a higher SPL rating throughout but rolls off about 5dB lower at 80 Hz.
ie. 90dB at 80Hz instead of 95dB (Fostex FE-208es)
So what does all this mean?
David
ok i am now torn between the PHL, ATC and ScanSpeak Revealator?
what tweeter (other than brands listed above.....raven, B&G, scanspeak ring, etc..) and woofer (Lambda?) would one recomend for a nice 3 way. I dont want to get 2 complicated and when one is paying top dollaor for driver the driver better behave over a large range and hence the concept of making a simple 3 wya using some good drivers.
the bass will be TL or dipole. only thing is how much bass do i loose in a dipole. that is much more air must be moved to produce the same bass levels in a dipole as opposed to TL or sealed.
the mid will be open baffle.
what tweeter (other than brands listed above.....raven, B&G, scanspeak ring, etc..) and woofer (Lambda?) would one recomend for a nice 3 way. I dont want to get 2 complicated and when one is paying top dollaor for driver the driver better behave over a large range and hence the concept of making a simple 3 wya using some good drivers.
the bass will be TL or dipole. only thing is how much bass do i loose in a dipole. that is much more air must be moved to produce the same bass levels in a dipole as opposed to TL or sealed.
the mid will be open baffle.
navin said:
I am in a very similar situation, and can tell one thing: the general agreement between almost everyone is that the ATC soft dome is probably the best midrange money can buy, but it does not represent a wide range in any terms... The company reccomends a low cross over point of 350 Hz, but I have not seen any applications where it crosses over below 800 Hz. 500 Hz in this very critial range is almost one and a half octaves!
If a 3-way is what your are after, it seems the difference between the ATC and the SS Rev would be in the bass driver that you choose. If you get one that can reach up to 800, then ATC is a driver to consider. If on the other hand you want a dedicated driver for the bottom few octaves, you should use the SS Rev, as it has a huge flat range, although it will not go as loud I believe. As far as PHL, I am not sure. I will research PHL for this project further, if I come to believe that it will offer more resolution and neutrality then the SS Rev. On that note, I would love to hear some openions as to how the PHL compares to the Revelator in these and other departments.
my bass will have to be at best 2 x 12" if i use diploes and 1x12" or 10" if I use a TL.
question to retain a small front can i make a dipole like made by
http://www.diyaudio.com/forums/showthread.php?s=&threadid=17103
and use it side ways so the drivers fire sideways. the depth of teh diploe can then become the front of teh speaker and that can me made less than 12". can it?
i dont think my bass driver will go much above 250-300Hz. i would like the 250-3k range to be covered by s a single driver and even then since i dont intend to use high order XOs (2nd order at best) I would be considering mids that can handle a bit of the upper bass.
what about triangle? do they figure in this.
what does ATC say about their 3" domes. the Fs I see are quite low so they might be able to go as low as 300hz.
I figured a good bass unit till 250-300Hz, a superb mid from 300-3k and then a tweeter from 3k+. I would like the mid tweeter XO to be a series XO that usually means a slope less than 12b per octave.
The other problem I face if I use ATC is that the bass is very limited. teh SS might be better in that I can can then use the same mid as a midbass for center and rear channels. my systems will be 80% stereo and 20% HT but that 20% is for my wife so it IS important. This is the only way I can sneak the system in.
question to retain a small front can i make a dipole like made by
http://www.diyaudio.com/forums/showthread.php?s=&threadid=17103
and use it side ways so the drivers fire sideways. the depth of teh diploe can then become the front of teh speaker and that can me made less than 12". can it?
i dont think my bass driver will go much above 250-300Hz. i would like the 250-3k range to be covered by s a single driver and even then since i dont intend to use high order XOs (2nd order at best) I would be considering mids that can handle a bit of the upper bass.
what about triangle? do they figure in this.
what does ATC say about their 3" domes. the Fs I see are quite low so they might be able to go as low as 300hz.
I figured a good bass unit till 250-300Hz, a superb mid from 300-3k and then a tweeter from 3k+. I would like the mid tweeter XO to be a series XO that usually means a slope less than 12b per octave.
The other problem I face if I use ATC is that the bass is very limited. teh SS might be better in that I can can then use the same mid as a midbass for center and rear channels. my systems will be 80% stereo and 20% HT but that 20% is for my wife so it IS important. This is the only way I can sneak the system in.
I intend to followthe KISS principle.
Each driver should be good and extended so the XO is very very simple. in fact I would have loved to go single driver and have no XO at all but then most single drivers do not fulfill my bass SPL requirements (95db at 50Hz for stereo and 100db at 50Hz for HT) the reason there are 2 requirements is that bass QUALITY for stereo needs to be better than for HT. HT does ok with rumbles etc... for stereo bass needs to be well defined (hence my penchant for sealed/aperiodic boxes, TLs and now dipoles).
Each driver should be good and extended so the XO is very very simple. in fact I would have loved to go single driver and have no XO at all but then most single drivers do not fulfill my bass SPL requirements (95db at 50Hz for stereo and 100db at 50Hz for HT) the reason there are 2 requirements is that bass QUALITY for stereo needs to be better than for HT. HT does ok with rumbles etc... for stereo bass needs to be well defined (hence my penchant for sealed/aperiodic boxes, TLs and now dipoles).
atc mid
hi,
as i have mentioned before, i own a pair of atc scm 100sl passives....
atc states that they are crossed over at 350 hz and 3500 hz.
....and it works flawless, i have yet to try an amp that can kill these speakers.
the last big amp was the plinius 250 watts class a - and the speakers just laughed at it when we turned it all the way up.
my friends big amp just started to distort while the speakers barely moved.........!
the mid crossover filter is a 12/12 db and it has a notch filter for the resonance fq and a lc to tame the rising impedance.....!
those who clame that this driver doesn't go lower than 5-800 hz use a wrong filter....
the big active atc systems powers the 3" mid with a 200 watt amp/1 mid......350hz - 3500 hz....without any problems.
perhaps i should mention that these speakers was love at first site, i never heard anything like it.
best regards,
troels
hi,
as i have mentioned before, i own a pair of atc scm 100sl passives....
atc states that they are crossed over at 350 hz and 3500 hz.
....and it works flawless, i have yet to try an amp that can kill these speakers.
the last big amp was the plinius 250 watts class a - and the speakers just laughed at it when we turned it all the way up.
my friends big amp just started to distort while the speakers barely moved.........!
the mid crossover filter is a 12/12 db and it has a notch filter for the resonance fq and a lc to tame the rising impedance.....!
those who clame that this driver doesn't go lower than 5-800 hz use a wrong filter....
the big active atc systems powers the 3" mid with a 200 watt amp/1 mid......350hz - 3500 hz....without any problems.
perhaps i should mention that these speakers was love at first site, i never heard anything like it.
best regards,
troels
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