I read somewhere about a design using the 15PR400 in a transmission line enclosure? Right now I am just looking at a BR in a 150L enclosure tuned to about 40hz. But a TL may be interesting. Did GM have a design for one floating around?
Thanks!!!
Thanks!!!
Nope, just some BRs, though its specs 'begs' for an inverse tapered (ML)? TQWT.
Qts'
Periodically posted:
FYI/FWIW, IME and proved to my satisfaction when 'proofing' MJK's MathCad design programs against some of my own Tower/Column alignments from 'way back when', the vented TL (closed pipe) alignment (aka MLTL) range from ~0.312 - 0.624 Qts' seems technically good enough, i.e. from Keele's 6th order assisted bass reflex to his Extended Bass Shelf (EBS) alignment.
While the 'sweet spot' (mean) is a ~0.4412 Qts', a 'close enough' simple guideline is:
~0.403, Vb = Vas, Fb = Fs (constant tapered MLTL)
< ~0.403, Vb = < Vas, Fb = > Fs (inverse tapered MLTQWT)
< ~0.403, Vb = > Vas, Fb = < Fs (expanding taper MLTQWT/MLhorn)
Qts' = Qts + any added series resistance (Rs): http://www.mh-audio.nl/Calculators/newqts.html
Periodically posted:
FYI/FWIW, IME and proved to my satisfaction when 'proofing' MJK's MathCad design programs against some of my own Tower/Column alignments from 'way back when', the vented TL (closed pipe) alignment (aka MLTL) range from ~0.312 - 0.624 Qts' seems technically good enough, i.e. from Keele's 6th order assisted bass reflex to his Extended Bass Shelf (EBS) alignment.
While the 'sweet spot' (mean) is a ~0.4412 Qts', a 'close enough' simple guideline is:
~0.403, Vb = Vas, Fb = Fs (constant tapered MLTL)
< ~0.403, Vb = < Vas, Fb = > Fs (inverse tapered MLTQWT)
< ~0.403, Vb = > Vas, Fb = < Fs (expanding taper MLTQWT/MLhorn)
Qts' = Qts + any added series resistance (Rs): http://www.mh-audio.nl/Calculators/newqts.html
Nice!….and here I thought either giant box or Open Baffle were the only options for this driver.
ruler flat response to 4K not withstanding of course……..
ruler flat response to 4K not withstanding of course……..
ok so total hornresp beginner here. I DL the program and imported the txt file into the software. Not sure how to go from the numbers and the schematic diagram to the actual dimensions of said enclosure. I can for sure do some homework and look at tutorials. Just wondering if you can point me in the correct direction?
Thanks!
'con' (cm) are the distances from the top (i.d.) to the driver center to the vent center to the bottom (i.d.), so as HR notes, its axial length (HR only 'understands' round) is 122 cm, so it's up to you to decide its width x depth dims.
S1 - S4 are the cross sectional areas (cm^2) at the 'con' points
Ap, Lpt is the vent area, vent length, so assumes a typical ~3/4" thick panel
If wanting to fold it, use Brian's nifty program.
S1 - S4 are the cross sectional areas (cm^2) at the 'con' points
Ap, Lpt is the vent area, vent length, so assumes a typical ~3/4" thick panel
If wanting to fold it, use Brian's nifty program.
ok... so I use the MLTL version of his program? which one though?
maybe i need to educate myself a bit more in TL speaker design.
maybe i need to educate myself a bit more in TL speaker design.
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Huh? Not aware of a MLTL version per se, only the HELP/Input Wizard that allows one to choose the various requirements that make some form of (ML) TL.
As for 'educate', not much to know in that take a BR and elongate it enough to generate eigenmodes low enough in frequency to start damping (shortening) the vent for a given tuning. That's it, no matter the huckster's hype.
Right, just 'IMPORT'/'open' it and it auto loads as a complete new record for one to copy/save/modify/whatever.
DL the HR record file to the HR Import folder, then in HR: click File/Import/HR Record to choose it, then 'open' and it auto loads as a new record for you to save, etc. as you please.
My response was based solely on explaining why it has such a flat wide range response. 😉
That said, like any box alignment it depends on the needs of the app, so if one has a high output impedance tube amp, the lower/flatter the driver's impedance the better overall from an SQ POV.
For box loading in general, it only loads to the driver's upper, lower mass corners, so as you note, just depends on how much gain/dynamic headroom one desires over this relatively narrow BW.