SpeakerTalk

doc-do

I have the pair of B139 A6171, but can't choose the design : Ch. Rogers project, B.J. Webb, etc. Is anybody help me? The speakers will be used with three way amplifier, analogous with QUAD 405. Thanks

proffski

Why not start with something simple to build?
Most designs used quarter wave labyrinth, just go for you feel most comfortable with and with contemporary crossover improvements perhaps?
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I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
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doc-do · Posted: Wed Apr 22, 2015 5:43 am Post subject:

I'm not interested in easy costructions, because I had made many of them. I want to make TL speakers & that's why ask this question. The crossover is built in pre-amplifier, & I don't want to change it. It works good.

proffski · Posted: Wed Apr 22, 2015 11:23 am Post subject:

In that case this may give you a few ideas perhaps?

http://goo.gl/StvZ38 or http://tinyurl.com/muft428

http://goo.gl/uupIoM or http://tinyurl.com/otu9hyx

http://goo.gl/ezbY4d or http://tinyurl.com/n79qcyx

http://goo.gl/9dDL1V or http://tinyurl.com/q4bvvv8

http://t-linespeakers.org/projects/jakob/index.html
_________________
I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill

proffski · Posted: Thu Apr 23, 2015 11:46 am Post subject:

Sorry that the previous links did not work, I've mislaid my original scans from Hi-Fi News but these were discovered on the internet.
_________________
I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill

doc-do · Posted: Thu Apr 23, 2015 1:44 pm Post subject:

Thanks, I had understood it when try to open these pages. But all of them good in theory. I want to know any practical opinion. It will be much work to do the housing & I don't want to make a mistake.

speakerguru · Posted: Thu Apr 23, 2015 10:29 pm Post subject:

proffski · Posted: Fri Apr 24, 2015 12:05 pm Post subject:

Agreed! Calling the pipes or labyrinths a TL is a nonsense, but one often does so as almost everybody else does...
All pipes have resonances no matter how well damped they are, they will exhibit standing waves at various frequencies which by definition interact with the output from the bass speaker cone depending in which way it is moving. I would never build another “TL” no matter how good it sounds; many do not sound all that clever when presented with real bass as from an organ for example. It is an eye opener when doing a sweep of frequencies and monitoring as to what the output can be up to.

I am amazed to this day as to how good products from PMC can sound, I guess that somehow they have avoided the laws of physics somewhere along the line... Wink

_________________
I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill

doc-do · Posted: Sat Apr 25, 2015 11:05 am Post subject:

What is PMC? I don't know about...

proffski · Posted: Sat Apr 25, 2015 11:12 am Post subject:

SaSi · Senior Contributor 200+ Joined: 24 Aug 2008 Posts: 256

A related question...
What do you thing about using the Atkins design to build two enclosures with simply a B139 each and the low pass section of the xover to function as subs?

I am using a pair of R107 equivalent at the moment and reading about bass management and taming room modes, 4 subwoofers at the 4 corners is optimum. I'm thinking of putting the extra two enclosures at the rear corners.

doc-do · Posted: Mon Apr 27, 2015 8:43 am Post subject:

I have some data of different TL authors, but can't to choose the optimal project (recommended by somebody). The closed box maybe? But it was the last my construction with two " face-to-face" woofers. It's not interesting now

proffski · Posted: Thu Apr 30, 2015 9:13 am Post subject:

Some interesting stuff for perusal here...

http://p10hifi.net/planet10/TLS/downloads/Acoustic-Labyrinth-Olney.pdf

http://www.stereophile.com/floorloudspeakers/fried_model_g3_loudspeaker/

http://www.t-linespeakers.org/projects/steve/index.html

http://www.avsforum.com/forum/155-diy-speakers-subs/1438061-transmission-line-isobaric-subwoofer-home.html
_________________
I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill

proffski · Posted: Thu Apr 30, 2015 4:13 pm Post subject:

This site is down a lot but I'd urge some of you who still have the stamina and willpower to build loudspeakers to visit it.
The last few pages are certainly worth it!
Link: https://engineering.purdue.edu/ece103/LectureNotes/SRS_Speaker_and_Enclosure_Intro.pdf
_________________
I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill

surv1v0r · Introductory Contributor Joined: 23 Jun 2013 Posts: 9

Are you just starting with a pair of B139s or do you have mid-range and tweeter drivers as well?

If the former, go for a "Coffin" (http://www.t-linespeakers.org/classics/coffin/plans.html) and use smaller, more domestically acceptable speakers for the rest of the frequencies.