Rule of thumb: take whatever the nominal is and subtract from 3dB - 6dB from it. Because that's how much you'll lose via step loss in 99.9% of applications.
I did not say that. I said your baffle F3 will likely be around 579Hz, give or take, so you may [as in 'may'] not have significant losses at 700Hz. However, this depends on your baffle geometry and diffraction effects as well, so this is only a 1st order conjecture, no more.
Dynamic range [headroom] is a matter of sensitivity, linear excursion & distortion performance rather than the presence of crossover components per se.
Transient response in the mass-controlled region is a question of upper linear bandwidth limit, and in the rising response region down to enclosure load. The SB drive units have extremely low VC inductance, so this is more or less a non-issue, with the limiting factor being that the cones are optimised for piston operation over a more modest BW.
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Thank you ScottMoose,
I didn't understand what you wrote: you told me 86 dB for a 86.5 db rated (the 8 ohms version I talked about) and as The Edge showed more or less the same for the bafle size... so I took that -0.5 to 1 dB at the 700 hz cut-off I plan....
So I should choose the 4 ohms and that's what I planed saying what happen at 300 hz to 100 hz where there is -3 dB and -6 dB for The Edge...
For the Audax I just looked at Bl/mms. But if I'm looking ar the inductance, indeed the SB is winning certainly something close than 0.08 uH/1Khz (extrapoled from SB17NBAC Audioexcite measurment) vs for the Audax (datasheet) 0.38 uH.
The Audax is known to give a fast and dry feeling with a little chest punch behavior for its size.... with huge load 😱 (I'm more or less aware than all of that is about the load, group delay, phase and polarity at the end as the tweeter is needed for transcient listening). Where the CAC is whorring is the breaks ups for a 6db low pass.. but maybe at 700 hz it doesn't arm at all and I will not see it in the trebles... at least I can notch I assume but it adds to the complexity... It's a little copper vs wood than choosing beteen both ! HD of the SB winns however 🙂
Not sure I understand about the band width in the pistonic range of a bass driver for the transcient. the more it's flat in the highs, the best for transcient even if Xoed way lower ? If for instance both the Audax and SB are loaded sealed for illustration at 0.5 Qtc, so faster group delay, will one give subjective better transcient at listening at iso Xover and upper drivers ? The AUdax exhibits a flater higher frequency drop at 30° (according datasheet)
I didn't understand what you wrote: you told me 86 dB for a 86.5 db rated (the 8 ohms version I talked about) and as The Edge showed more or less the same for the bafle size... so I took that -0.5 to 1 dB at the 700 hz cut-off I plan....
So I should choose the 4 ohms and that's what I planed saying what happen at 300 hz to 100 hz where there is -3 dB and -6 dB for The Edge...
For the Audax I just looked at Bl/mms. But if I'm looking ar the inductance, indeed the SB is winning certainly something close than 0.08 uH/1Khz (extrapoled from SB17NBAC Audioexcite measurment) vs for the Audax (datasheet) 0.38 uH.
The Audax is known to give a fast and dry feeling with a little chest punch behavior for its size.... with huge load 😱 (I'm more or less aware than all of that is about the load, group delay, phase and polarity at the end as the tweeter is needed for transcient listening). Where the CAC is whorring is the breaks ups for a 6db low pass.. but maybe at 700 hz it doesn't arm at all and I will not see it in the trebles... at least I can notch I assume but it adds to the complexity... It's a little copper vs wood than choosing beteen both ! HD of the SB winns however 🙂
Not sure I understand about the band width in the pistonic range of a bass driver for the transcient. the more it's flat in the highs, the best for transcient even if Xoed way lower ? If for instance both the Audax and SB are loaded sealed for illustration at 0.5 Qtc, so faster group delay, will one give subjective better transcient at listening at iso Xover and upper drivers ? The AUdax exhibits a flater higher frequency drop at 30° (according datasheet)
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As Scottmoose said.
You will usually allow for 3 - 6dB baffle step loss.
Therefore your woofer sensitivity decides overall system sensitivity.
It's ok to have a too sensitive mid and tweeter. Padding a mid is not as evil as people make out. Resistors don't seem to be cursed with any signal degradation. Just make sure for mid padding you allow a good 40w or more dissipation. Like all passive networks - I play them at volume for a while and feel heat to determine which resistors are handling it. XSim (?) also shows power dissipation to check.
My current 3 ways are 84dB sensitive. They comprise an 87dB nominal woofer, 87dB nominal midrange and 90dB tweeter.
You often get a little gain if you are closely spacing both Fc points in the midrange - so a slightly lower sensitivity midrange is not the end of the world.
Best thing to do is model and see where you land. Don't rush using factory curves - apply your baffle signature and bafflestep loss. Jeff's frequencey response combiner is excellent here when combining with a tool like Edge.
Get the input data right - and you'd be surprised how close your sims are to measurements . Speaker design is a methodical, disciplined exercise.
The above are of course for on-axis which isn't the full story with speaker design.... but hey - it's a start for evaluation.
You will usually allow for 3 - 6dB baffle step loss.
Therefore your woofer sensitivity decides overall system sensitivity.
It's ok to have a too sensitive mid and tweeter. Padding a mid is not as evil as people make out. Resistors don't seem to be cursed with any signal degradation. Just make sure for mid padding you allow a good 40w or more dissipation. Like all passive networks - I play them at volume for a while and feel heat to determine which resistors are handling it. XSim (?) also shows power dissipation to check.
My current 3 ways are 84dB sensitive. They comprise an 87dB nominal woofer, 87dB nominal midrange and 90dB tweeter.
You often get a little gain if you are closely spacing both Fc points in the midrange - so a slightly lower sensitivity midrange is not the end of the world.
Best thing to do is model and see where you land. Don't rush using factory curves - apply your baffle signature and bafflestep loss. Jeff's frequencey response combiner is excellent here when combining with a tool like Edge.
Get the input data right - and you'd be surprised how close your sims are to measurements . Speaker design is a methodical, disciplined exercise.
The above are of course for on-axis which isn't the full story with speaker design.... but hey - it's a start for evaluation.
Thank you for your input.
could look like this : SB17CAC 4 ohms + SS 10F/8424G00 8 ohms + SB29RDNC or the Peereless or Seas 27TFFNCG or Peereless OT19NC00
W - M - T
4 Ohms - 8 Ohms - 4 Ohms
90/91 dB (w/o baffle loss) - 87.5 dB - 90 db up to 94 dB /2.83V according the tweet. Or w/o the tweet if in a little room the Scan Speak has enough high end with some toe in...
Perhaps with the W sealed with a 45 to 55 hz -f3 according the real T&S of the SB17CAC35-4...
I have purchased the parts for an Arta Box...
If Oldspeakerguys likes the SB CAC after a Satori (we listen to same music genres) and the driver is also used in the Philarmonic Loudspeaker, I can not go wrong with this SB purchase but just miss the design... which is not a problem as it is for learning after having too much measured my branded loudspeakers.
Thanks guys for all the precious advices given
.
could look like this : SB17CAC 4 ohms + SS 10F/8424G00 8 ohms + SB29RDNC or the Peereless or Seas 27TFFNCG or Peereless OT19NC00
W - M - T
4 Ohms - 8 Ohms - 4 Ohms
90/91 dB (w/o baffle loss) - 87.5 dB - 90 db up to 94 dB /2.83V according the tweet. Or w/o the tweet if in a little room the Scan Speak has enough high end with some toe in...
Perhaps with the W sealed with a 45 to 55 hz -f3 according the real T&S of the SB17CAC35-4...
I have purchased the parts for an Arta Box...
If Oldspeakerguys likes the SB CAC after a Satori (we listen to same music genres) and the driver is also used in the Philarmonic Loudspeaker, I can not go wrong with this SB purchase but just miss the design... which is not a problem as it is for learning after having too much measured my branded loudspeakers.
Thanks guys for all the precious advices given
.I still like the Satoris better than the CAC but the CAC are growing on me. The Satoris just have that extra bit of refinement and another inner layer of what I call "micro-detail" (not my words, someone else came up with that term but I think it is a good term for sure). But, the CAC do have really low distortion; I haven't tried them with a higher quality tweeter yet though. I may have them sold before I get that far.
best regards!
best regards!
I am very enthusiastic about the SB17CAC-35. I use the 4 ohm version in an active 3 way. I chose the 4 ohm flavor because my amps seem to prefer 4 ohm loads slightly better than 8 ohm loads.
Very good resolution of detail, very realistic dynamics. I will soon be developing a new system based on Satori textreme drivers, but my going-in expectation is that the textreme drivers will provide slightly more resolution. It will not be a big change because the SB17CAC35 + SB26CDC combination is already so excellent. I have said it before: if the SB17CAC35 and SB26CDC were priced at twice the current price, they would still be a bargain. At the current price, they are fabulous.
Having said that, a designer must take care in using the SB17CAC35 in a passive system. The 7-8 khz resonance must be suppressed. A good paper cone can be easier to work with.
Very good resolution of detail, very realistic dynamics. I will soon be developing a new system based on Satori textreme drivers, but my going-in expectation is that the textreme drivers will provide slightly more resolution. It will not be a big change because the SB17CAC35 + SB26CDC combination is already so excellent. I have said it before: if the SB17CAC35 and SB26CDC were priced at twice the current price, they would still be a bargain. At the current price, they are fabulous.
Having said that, a designer must take care in using the SB17CAC35 in a passive system. The 7-8 khz resonance must be suppressed. A good paper cone can be easier to work with.
agree on the CAC needs special X/O care. Great as a woofer in a smaller 3-way; a little tricky in a 2-way but worth the extra effort; still playing with mine; trying also to sell them; gently used, never soldered (see SWAP shop for details)
cheers!
cheers!
well, I have my current system listed under 3 1/2 way...upgrades, etc. I will stick with that but am also going to sell the SB29s (see swap shop for details) and buy 2 more Peerless NE225 W08 HS. that is short term.
I am hoping for the TexTreme MR 13 mids to come out soon; then I might replace my Satori MR16 and MA Pluvia 7PHD combination with the TexTreme mids!???
I am hoping for the TexTreme MR 13 mids to come out soon; then I might replace my Satori MR16 and MA Pluvia 7PHD combination with the TexTreme mids!???
Do you think a // LCR with the CAC is ennough or should it be a serie LCR for pad down this peak please ?
Textrene is appealing but very too much expensive for me, and this is a project for learning. I'm glad that good drivers can be sourced for an aceptable price as the CACs.
The Audax HM170Z0 was appealing but I believe its 40 hz higher Fs and the need of a bigger cabinet as not as good Le are less atrractive... But the natural high end dropping is certainly easier to deal with for a beginner as I...
@ Oldspkeakerguy... yeah I know you will finish with the Textremes 🙂 ; Edit : can not remember, did I talk to you of the Bach's Cello take by Alisa Weilerstein ???
@Hifijim : was is a 3 ways with the SB17CAC as a mid ?
Would you go for the cac tweeter as well or the sb29 RDNC with its 72 mm diameter is better in a context of a 3000/3500 XO please ?
Textrene is appealing but very too much expensive for me, and this is a project for learning. I'm glad that good drivers can be sourced for an aceptable price as the CACs.
The Audax HM170Z0 was appealing but I believe its 40 hz higher Fs and the need of a bigger cabinet as not as good Le are less atrractive... But the natural high end dropping is certainly easier to deal with for a beginner as I...
@ Oldspkeakerguy... yeah I know you will finish with the Textremes 🙂 ; Edit : can not remember, did I talk to you of the Bach's Cello take by Alisa Weilerstein ???
@Hifijim : was is a 3 ways with the SB17CAC as a mid ?
Would you go for the cac tweeter as well or the sb29 RDNC with its 72 mm diameter is better in a context of a 3000/3500 XO please ?
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I haven't decided on X/O for the 17CAC for myself; like I said; I am playing around with them and may get them sold before I do any final design. For my usual way of doing things; I chose a mid and tweeter with higher sensitivity so I can pad them down to match the woofer or mid/woofer once it is in it's final box and final room for listening. That would also give more flexibility with any baffle step. (Rarely do I ever try to match exact sensitivities of all drivers based on a spec sheet alone). If you cross low enough; I think a 2nd order should be fine, if you cross higher; 2nd order might still work but you may need a Zobel. If you cross even higher; maybe a notch would help. This is where the sims and 3rd parties help; I don't have any sim software myself; those others out there with better hardware and software and measuring tools can better answer these types of questions.
I saw a circa 25 liter sealed is giving a good 0.61 Qtc... appealing for the ones that have a sub....
16 liter is the flat 0.7 Qtc.
I will cut-off it between 650/750... cause the values of the inductors on shelves... well mayb with Arta box I can measure an inductance and remove some turns to adjust...
16 liter is the flat 0.7 Qtc.
I will cut-off it between 650/750... cause the values of the inductors on shelves... well mayb with Arta box I can measure an inductance and remove some turns to adjust...
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I do closed box Q less than 0.707 usually these days because I DO have a good subwoofer. (also; Aperiodic vent). Transients are just as important as phase and frequency response in my way of thinking. Of course; it all comes back to the room; the room has the most effect on bass. In a perfect world; my dream listening room would be like a small auditorium; no parallel surfaces including all walls, floor, ceiling, etc.
A dreamer has to dream! (even if it will never come to pass)...FWIW...
A dreamer has to dream! (even if it will never come to pass)...FWIW...