Corner Horn for TB W8-1772

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hello everyone,

I have a dilemma with my listening room: It is only 3.5 meters (11'6") wide x 5 meters (16'5") long.

It is small for a rear loading horn and I would like to have a high sensitivity horn for my SET 845 amp.

I have 2x TB W8-1772 speakers.

Hence the question: Would a corner horn solve the problem?

If yes, would the calculation be the same as a rear loading horn with the horn split in 2?
Ideally I would like the frequency response to be 30hz - 20khz (-3dB)

I have a CNC router, so the internal curves would not be hard to build.

Thanks and regards,
Dieter
 
Last edited:
rdh20

i made a few solutions for such driver,
look RDH20 and Schalmei sat
 

Attachments

  • RDH20 TB1772 monacorSPH-210 web.jpg
    RDH20 TB1772 monacorSPH-210 web.jpg
    128.9 KB · Views: 520
  • schalmei_riethweb4.jpg
    schalmei_riethweb4.jpg
    170.9 KB · Views: 568
i made a few solutions for such driver,
look RDH20 and Schalmei sat

Hello Horst,

thanks for the hints! I checked your website which is great!

I share your opinion in regards to X-overs :nod:

I am slightly more radical :D and would like to have point source, with only one driver.

Decware has a nice design, but only for 6,5" drivers
http://www.decware.com/CORNERHORNPLANS.pdf

A Tannoy corner horn, looks quite nice, but don't think that such a large box would fit my room.

The Voigt horn ist also nice, however it is way beyond my abilities to build.
retro vintage modern hi-fi: Voigt Domestic Corner Horn

Taking your principle of 2 drivers, would it be feasible to use one driver and have 2 horns front and rear loading? Like Lowther Imperator?

Thanks and regards,
Dieter
 
frugal-phile™
Joined 2001
Paid Member
The TB W8-1772 is not super efficient, the ones i have had thru here have averaged just under 92 dB. A back loaded horn wil only increase the gain in the bass, potentially eliminating the need for any baffle step compensation.

SE 845, unless you want harm inducing SPL, should be more yjam enuff power for this driver in almost any box. It may well not be able to trptoduce all the low level information that your SET feeds it thou.

A horn for this driver would need to be specifically designed for the it.

dave
 
The TB W8-1772 is not super efficient, the ones i have had thru here have averaged just under 92 dB.
dave

Hey Dave, what a rip off! They sell it as having 95dB SPL :mad:
Microdynamics would have been thankful for these extra 3dB, anyways, budget was short for a pair of Lowthers.

If some day I decide to "solder" a 300B, I will probably need other speakers.

Hey Freddi,

this is an interesting design, how should I understand the front panel blue line?
will it be another plywood in the front of the front panel or will it replace the front panel?

Thanks and regards,
Dieter
 
1772 not suitable for good horn. If you use in 10-16l horn chamber and 3m horn lengh you will get just 55-60hz then big dip then 120hz peak. I tried 1772 in jericho horn, it was a big mistake, its sounds horrible and boomy on 60 and 120hz... I put nirvana 6.5 in this horn with correction of chamber and horn throat . so it goes lower than 40hz without any dips and peaks, and you can hear any bass note. Actualy hornresp shows this very close to real. I also tried to silumate recomended TB horn and its looks poor than jericho horn
 
Last edited:
hi Dieter - - regarding the Karlsonator8 drawing, the blue lines are an alternate aperture. I think it may be beneficial to extend the aperture all the way to the top but not have it quite as open or wide up there as with the blue lines.

Here's my tall 18" conventional Karlson-type with a narrow upper aperture. If I cover the first 8 inches from top - downwards, then it loses some subjective "speed" (why?)

http://i.imgur.com/kMwSfs1.jpg

here's the Karlsonator12 aperture - Karlsonator12 tunes to 37Hz, which
is too low for some drivers

http://i.imgur.com/I1YiIFW.jpg

here's a clip of that K18 with K-tube mounted inside the front chamber - thankfully, it sounds better in person
YouTube
 
Last edited:
Hello everyone,

many thanks for the suggestions and great discussion.

I have been simulating some cabinets in AJHorn and even the original TB horn suggestion does not seem to bring hifi results. :confused:

After simulating that jazz for a few hours, I came to the conclusion that with that driver a horn can only work with internal absorber, below you can find the simulation.
 
Hello everyone,

many thanks for the suggestions and great discussion.

I have been simulating some cabinets in AJHorn and even the original TB horn suggestion does not seem to bring hifi results. :confused:

After simulating that jazz for a few hours, I came to the conclusion that with that driver a horn can only work with internal absorber, below you can find the simulation.

Same conclusion as mine. But it's not solve problem completely, this drivers don't have enough BL/mms for BLH
 
Last edited:
when 1772 was introduced, there was a fairly large (6.8 cubic foot external bulk) factory blh plan. "This" PDF plan is probably it. SUG1-19 - 8” Full Range Back Horn Enclosure Suggestion - TB SPEAKER CO., LTD.

as you can see by the dimensions and 2.5 meter path, it seems to be optimized to give some gain towards the bottom. 15mm Baltic birch might be stiff enough as there's a lot of inherit bracing.

aNLsBCj.jpg
 
Last edited:
when 1772 was introduced, there was a fairly large (6.8 cubic foot external bulk) factory blh plan. "This" PDF plan is probably it. SUG1-19 - 8” Full Range Back Horn Enclosure Suggestion - TB SPEAKER CO., LTD.

as you can see by the dimensions and 2.5 meter path, it seems to be optimized to give some gain towards the bottom. 15mm Baltic birch might be stiff enough as there's a lot of inherit bracing.

aNLsBCj.jpg
In my experience 18-19mm is minimal acceptable value forbracing and others parts of horn
 
frugal-phile™
Joined 2001
Paid Member
...anyway I will build a horn and something that I don't know how to call, something like a BR with linear function.

What you have drawn is a tapped horn — a horn where the driver is loaded part-way along the horn. The Voigt is likely the best known example. For optimum performance you need to use all the tricks. Two primary ones are driver offset from the closed end, depending on the horn flare, typically ⅓ to ½ the horn length and the use of a restricted terminus — something found to be very useful in smotthing the LF performance of a Voigt (making it an ML-Voigt).

attachment.php


For some good modern examples check of the Metronome & the Frugel-Horns. And to answer ahead of time, a FH for 8” drivers becomes so large as to become impractical.

dave
 

Attachments

  • tapped-horn.png
    tapped-horn.png
    22 KB · Views: 817
frugal-phile™
Joined 2001
Paid Member
In my experience 18-19mm is minimal acceptable value forbracing and others parts of horn

Freddi’s suggestion is a Olson/Nagoka style horn. They can work well but need to be carefully designed for the driver. Given some of the other so-called horns TB has recommended i would be careful with this one.

As the the comment about materials, if one uses good 15mm ply it is likely to be sufficient. With all the internal panels and the shown braces the box is inherently stiff (might need a bit of help in the mouth). 15mm is superior to ¾” MDF by some margin. We make the Frugel-Horn Mk3 & FHXL with 15mm play and the FH-Lite with 12mm. Even the large Woden double mouthed horns are fine with 15mm (with additional strategically placed braces).

dave
 
Last edited:
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.