There's a new lady in the house.....
Careful, she's a bit shy...
Any suggestion for cabinet vol and port length / width would be hugely appreciated.
Parameters as follows:
Careful, she's a bit shy...
Any suggestion for cabinet vol and port length / width would be hugely appreciated.
Parameters as follows:
| Nominal Diameter | 24” / 610 mm |
| Voice Coil Diameter | 6.08” / 152 mm |
| Power Rating 1 2 * | 1800 W (A.E.S.) |
| Available Impedance | 8 Ohm |
| Sensitivity (1W/ 1m)* | 98 dB |
| Frequency Range | 20 Hz - 200 Hz |
| Peak Power (6 dB Crest Factor) | 7200 W (A.E.S.) |
| Resonance | 34 Hz |
| Voice Coil Winding Depth | 37.00 mm / 1.46” |
| Recommended Enclosure Volume | 150 - 220 Litres |
| Flux Density | 1.5 Tesla |
| Magnet Material | Neodymium |
| Magnet Gap Depth | 15.0 mm / 0.59” |
| Former Material | Glass Fibre |
| Dust Dome Material | Solid Paper |
| Voice Coil Material | Copper |
| Cone Material | Paper |
| Suspension Material | Fabric |
| Surround Material | Fabric |
| Fs | 34 Hz |
| Re | 5.3 Ω |
| Qms | 9.92 |
| Qes | 0.32 |
| Qts | 0.31 |
| Le (@ 1 kHz) | 4.01 mH |
| Le (@10 kHz) | 1.51 mH |
| Vas | 355 Litres |
| Mms | 440 g |
| Sd | 2239 cm2 |
| Cms | 49.8 μm/N |
| BL | 39.46 T/m |
| Xmax | 16.00 mm |
| Vd | 3.58 Litres |
| Ref. Efficiency | 4.19 % |
| EBP | 106.25 Hz |
Vintage spec driver, so many of the pioneer's cabs will work or with a modern max flat ~149 L net/44 Hz tuning, though the pioneer's ~247 L net/actual Fs acoustically optimal BR would be my choice.
Anyway, its specs allows many alignments, so maybe best to tell us any size, room placement constraints, preferred type(s) musical/whatever playback at average SPL, etc..
Anyway, its specs allows many alignments, so maybe best to tell us any size, room placement constraints, preferred type(s) musical/whatever playback at average SPL, etc..
What? Vintage, are you having a laugh?
Of course, everyone here knows that vintage drivers had power handling of 1.8Kw, 98dB sensitivity and a BL force factor in excess of 39. Clearly i have stepped into clown college here? Forget it, I'll go elsewhere for a more sensible response. Nice going!?
Good bye.
Mods
Please feel free to remove this thread.
Regards
Rich
Of course, everyone here knows that vintage drivers had power handling of 1.8Kw, 98dB sensitivity and a BL force factor in excess of 39. Clearly i have stepped into clown college here? Forget it, I'll go elsewhere for a more sensible response. Nice going!?
Good bye.
Mods
Please feel free to remove this thread.
Regards
Rich
Last edited:
Rich,
An Fb of 15Hz or one of 34Hz (or higher) will suggest quite different cabinet volumes, port lengths / areas.
There will be trade offs between port velocity, drive level, Fb, and port resonance that are all length and area dependent. The alignments are literally endless.
It has been 14 years since you said you'd buy a P.D.24, have your ideas changed since that era?
Art
An Fb of 15Hz or one of 34Hz (or higher) will suggest quite different cabinet volumes, port lengths / areas.
There will be trade offs between port velocity, drive level, Fb, and port resonance that are all length and area dependent. The alignments are literally endless.
It has been 14 years since you said you'd buy a P.D.24, have your ideas changed since that era?
Art
Rich, ran the T/S parameters & I got this...the EBP at a very high value points toward a vented alignment. The standard values thru the simulation came out kinda lame, so upon "tweaking" I got this monster to perform better.
An internal volume of 310 liters, tuned frequency of 41 hertz...and we get a best performance of -3.03 Db at 38.35 hertz. Port came in at 300mm high, by 400mm wide, slight rectangular, 422mm long inside.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Rick...
An internal volume of 310 liters, tuned frequency of 41 hertz...and we get a best performance of -3.03 Db at 38.35 hertz. Port came in at 300mm high, by 400mm wide, slight rectangular, 422mm long inside.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Rick...
sensible response: get a free sim app like WinISD and play around with it until you find something workable
Using the common enclosure ratio of 0.618/1/ 1.618 ...this gets you an internal dimensions of 676mm Wide, 417mm Deep, and 1093mm Tall. The 24 inch driver is almost the full width of this enclosure, the port volume is such that the big driver needs to be near the top. Grab a piece of paper & a ruler & start drawing out the dimensions...compensate for the volume of the port as to make the enclosure slightly larger.
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--------------------------------------------------------------------------------------------------------------------------------------------------------Rick...
No, serious as a heart attack, just apparently a lot more educated/experienced on the subject than you, i.e. its T/S theory specs that govern box design are very close to the '40s - '60s era Altec, EV, etc., drivers I used and still used for some prosound apps, so lots of options or can design one to suit the needs of YOUR app if you tell us what it is.
Are you on your period?
And honestly over here is more relaxed than the other popular audio gathering place where they lock a thread cause you do not say something that the moderator like.or they ban people cause they don't endorse the brands they like.
It would seem that "Rich" here didn't want to bother with doing the work by himself, AKA "Do it Yourself", DIY...Frankly these giant drivers do the "tub thumping" thing, a one note driver, kinda useless. I'm guessing those thirty-inch Electrovoice drivers of long ago were similar & had a very narrow role in making music. Sorry, thirty eight hertz down three Db ain't much to write home about.
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-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Rick...
No need to "listen for yourself"...assuming the TS parameters are relatively accurate...I know what 100 hertz, fifty hertz, thirty hertz sounds like...and the response falling away at only 38 hertz is NOT a "great" performance for a woofer, mediocre at best.
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------Rick...
Nope, have you?....we have our TS parameters to work with...let's not guess at things, OK? "Bigger is better" is not a valid truism.
_________________________________________________________________________________________________________________Rick...
@Richard Ellis
So on purely some small signal parameters you can tell how a driver sounds? Thats really handy...
How can you say response drops of after 38Hz?
Would you call most PA 18's/21's also one note drivers?
So on purely some small signal parameters you can tell how a driver sounds? Thats really handy...
How can you say response drops of after 38Hz?
Would you call most PA 18's/21's also one note drivers?
"...how a driver sounds" is a subjective term. How deep in frequency is what we are trying to achieve...how low in hertz...when it stops performing and at how much decibels it falls away.
Now, just how these low frequencies propagate thru any one listening space...well, that's a whole nother' issue...room acoustics.
How can I say response drops off after 38 hertz?...it's right there on the graph!!! Eighteen inch drivers seems about the limit, even with ultra-light materials, past that the square-cubed law starts to interfere here, cone control getting harder & harder.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Rick...
Now, just how these low frequencies propagate thru any one listening space...well, that's a whole nother' issue...room acoustics.
How can I say response drops off after 38 hertz?...it's right there on the graph!!! Eighteen inch drivers seems about the limit, even with ultra-light materials, past that the square-cubed law starts to interfere here, cone control getting harder & harder.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Rick...
Which graph are you referring to? The 975L CB one on the specsheet? Or a simulated response?
Both don't tell much imho and only points you in a direction. Its older brother the PDN2150 has been used in multiple environments including larger PA's and none describe it as uncontrolled. The 246003 is a noticeable improvement over the 2150 in lineair excursion and control.
In the future I am possibly in the situation to post some measurements of the said drivers.
Both don't tell much imho and only points you in a direction. Its older brother the PDN2150 has been used in multiple environments including larger PA's and none describe it as uncontrolled. The 246003 is a noticeable improvement over the 2150 in lineair excursion and control.
In the future I am possibly in the situation to post some measurements of the said drivers.
I would have thought most all of us here have one or more simulation programs, so one can model a drivers performance...my bad, sorry. One of the first simulations commonly available is "WinISD", the beta version...it's freely available , one just plugs in the TS parameters & the program gives you a sealed, ported, 4th order and sixth order bandpass enclosures. It calculates optimum sizes(volumes), for ported enclosures, box volumes, tuning frequencies along with port sizes, shapes....all of this graphed out for you. With experimentation you can really turn a turd of a driver into its best possible...Additionally you can see starkly some really unsuitable & performing drivers...no matter how one tweaks things, some are truly bad..& you can see it right there on the graphing....despite some silly fawning over one particular driver, the graphed out performance is right there to see & shake your head & roll your eyes....facts vs. "impressions"...or myths, take you pick. Load it up & try it for yourself, it can be quite revealing...."so that's why this sounds like it does?".
--------------------------------------------------------------------------------------------------------------------------------------------------------------------Rick...
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Oh, I am well aware of WinISD, Hornresp, Bass box professional , Akabak etc. You can simulate anything you want, if you do not verifie the things you simulate vs real world testing, the model is not very usefull. For me personally, simulation software like winsisd and (mostly) hornresp are only there to point me in some direction. Eventually the real world testing will give you what you want, and I take that anytime over some response plots in winISD. Hell even real "impressions" would be placed above a winISD response plot.
If that's not your thing, lets agree to disagree
If that's not your thing, lets agree to disagree