Hi guys,
I recently got a pair of Fostex H400 horns.
They were in bad condition.
So I decided to make them pretty again and use them with a pair of Beyma CD11Nd or CP385Nd which I have at hand.
This is what came out
For the moment I paired them with my PPD Subs. Just to hear what the horns are capable of.
The PPD subs are supposed to play up to 300-400hz. So this is by far no perfect match crossed at 1k.
But I really like what I hear from the horns
I recently got a pair of Fostex H400 horns.
They were in bad condition.
So I decided to make them pretty again and use them with a pair of Beyma CD11Nd or CP385Nd which I have at hand.
This is what came out
For the moment I paired them with my PPD Subs. Just to hear what the horns are capable of.
The PPD subs are supposed to play up to 300-400hz. So this is by far no perfect match crossed at 1k.
But I really like what I hear from the horns
I have a pair of RS225-8 laying around. So I stumbled into the thrad '10F+RS225 FAST' and decided at last (after some advice from XRK) to build a pair of tml enclosures for the Daytons.
The enclosures are to tall for my taste when I want to put the horns on top.
I am aiming for outer Dimensions of roughly 40x30x75 cm
So with 5cm Granite bases the center of the mid/hights horn will be 90cm from ground.
I unfolded XRKs tmls to evaluate the geometrics.
The tml is about 95inch (241cm) long.
Cross section starts at 68sq inches (438cm²) and ends at 2.25 sq inches (137cm²). The cross section tappers very evenly across the length.
So how to fold the TML into my preferred enclosure dimensions?
The enclosures are to tall for my taste when I want to put the horns on top.
I am aiming for outer Dimensions of roughly 40x30x75 cm
So with 5cm Granite bases the center of the mid/hights horn will be 90cm from ground.
I unfolded XRKs tmls to evaluate the geometrics.
The tml is about 95inch (241cm) long.
Cross section starts at 68sq inches (438cm²) and ends at 2.25 sq inches (137cm²). The cross section tappers very evenly across the length.
So how to fold the TML into my preferred enclosure dimensions?
The difficulty is to fold it to the enclosure dimensions with driver on the upper half and the opening at the front.
So here are some attempts which are more or less having the desired geometry.
All my attemts are bases on an inner width of 25cm.
This one is 250cm long with an opening of 142cm² starting at 400cm².
The next one is more complex to build because of the no 90°angles.
This is 230cm long ending in 125cm²
This is a short one
190 long, 142cm² mouth
All these simulate in hornresp very similar.
The shorter one need some more stuffing to get the response more even.
At the end I think it makes not a big difference.
I will cross the tml at 1k-1.2 k to the horns actively with minidsp.
So here are some attempts which are more or less having the desired geometry.
All my attemts are bases on an inner width of 25cm.
This one is 250cm long with an opening of 142cm² starting at 400cm².
The next one is more complex to build because of the no 90°angles.
This is 230cm long ending in 125cm²
This is a short one
190 long, 142cm² mouth
All these simulate in hornresp very similar.
The shorter one need some more stuffing to get the response more even.
At the end I think it makes not a big difference.
I will cross the tml at 1k-1.2 k to the horns actively with minidsp.
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Hi, since you have a subwoofer the extra effort of building a pipe resonator isn't needed. But your sketches are good!
This is interesting. I’ve been thinking about an 8” or 10” driver in a transmission line for bass use under some front horns.
No RS225-8 on hand…They are cheap enough to get a pair.
I have a variety of 8” like some B&C 8pe21 and Fostex 208ez etc
I wish I could wrap my head around hornresp better and design something like this.
Do you have any internal dimensions?
No RS225-8 on hand…They are cheap enough to get a pair.
I have a variety of 8” like some B&C 8pe21 and Fostex 208ez etc
I wish I could wrap my head around hornresp better and design something like this.
Do you have any internal dimensions?
Pretty good write up on getting Hornresp going
https://diy.midwestaudio.club/discussion/comment/61331#Comment_61331
https://diy.midwestaudio.club/discussion/comment/61331#Comment_61331
Nice work…….but with the low Fs of the 225s and their damped construction, I don’t see any need for a horn application in this case.
I would get two more though and wire them in parallel per side with a .5 inductor in line with the bottom woofer to combat baffle step and eliminate lobing to the horn. Will blow the doors off your horn solution in resolution, distortion and midbass impact.
I would get two more though and wire them in parallel per side with a .5 inductor in line with the bottom woofer to combat baffle step and eliminate lobing to the horn. Will blow the doors off your horn solution in resolution, distortion and midbass impact.
So this is an even taper from 350cm² to 138cm² at 248cm length.
Inner width 25 cm. Outer walls 22 thick, inner walls 16.
Inner width 25 cm. Outer walls 22 thick, inner walls 16.
The latest one
350cm² to 138cm², 248cm length
So what do you think?
350cm² to 138cm², 248cm length
So what do you think?
Actually, yesterday while writing I was thinking of the old triangular base TL design around the B139 woofer.
That would be a good match with the horn!
That would be a good match with the horn!
I like this one:
It’s odd that the predicted impedance doesn’t have a double peak with a dip in the middle characteristic of a vented alignment. The midpoint between the peaks is the cabinet TL Fs.
It’s odd that the predicted impedance doesn’t have a double peak with a dip in the middle characteristic of a vented alignment. The midpoint between the peaks is the cabinet TL Fs.
Except that design by Bailey isn't a proper transmission line - I'm sure Planet10 can provide more detail on that issue.
page 215 A.R Bailey
https://www.worldradiohistory.com/UK/Wireless-World/70s/Wireless-World-1972-05.pdf
similar ? VSonics TL-AKSA
(Modeling ?)
https://web.archive.org/web/20110926081449/http://www.aksaonline.com/products/products_Vsonics.html
https://www.audiocircle.com/index.php?action=gallery;area=browse;album=2123
https://www.audiocircle.com/index.php?topic=70732.0
VSonics woofer
SEAS CA22RNY/H1471 Prestige Series 8" handcoated paper cone
vas 82 litresqms 1.69
qes .36
qts .30
https://www.madisoundspeakerstore.com/approx-8-woofers/seas-h1471-ca22rny-8-paper-cone-woofer/
Dayton RS225-8
vas 57 litres
qms 1.46
qes .51
qts.38
https://www.daytonaudio.com/images/resources/295-356--rs225-8-spec-sheet.pdf
========
post#31
https://www.diyaudio.com/community/...-aksa-the-saksa-85.294346/page-2#post-4790530
======
other TL
old 1995
OA-Transient II-Ronald Koot from SpeakerBuuilding.com
Scan-Speak 18W/8542-05 Vifa D27TG-35-06
https://web.archive.org/web/20101129145208/http://speakerbuilding.com/content/1033/
small Troels Scoperta
http://www.troelsgravesen.dk/W15LY001_HDS.htm
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? info ? modeling?
https://i.pinimg.com/originals/97/94/79/979479f456d18c54ba919f8833087420.jpg
Similar
page 32 FAST 10" woofer
https://kupdf.net/download/klang-ton-2012-01-pdf_58c009a3e12e893b26add375_pdf
IPL Speakers
https://www.alancoleman.co.uk/blog/...bon-transmission-line-speaker-project-part-1/
https://i.pinimg.com/originals/97/94/79/979479f456d18c54ba919f8833087420.jpg
Similar
page 32 FAST 10" woofer
https://kupdf.net/download/klang-ton-2012-01-pdf_58c009a3e12e893b26add375_pdf
IPL Speakers
https://www.alancoleman.co.uk/blog/...bon-transmission-line-speaker-project-part-1/
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