Is anyone thinking about building Walsh drivers?

I'm hoping to start a discussion that is not charged with emotion that may be useful to folks seeking to build Walsh transmission line drivers.
Any of you out there played with this seriously?
Hi Dale.

I'd much rather spend my time listening to Walsh speakers than building them.

Your speakers are on my short list of designs I have not heard that I would most like to.

Right now I am happy with what I have but always looking to explore new or future options.

I would make extra effort to go to Capital Audiofest this July if I knew you would be demoing your stuff!

I still have not heard anything that I can afford that would make me abandon Walsh style speakers for my tougher applications.

I do fear though that the expertise to make the technology work well in a marketable manner is so limited that it could fall totally by the wayside someday. That would be very sad!
Okay Dale,

I may have failed some kind of IQ test here, but I just followed my own link (above, in a previous post I made to this thread) and don't see any reference to a TLS 5 hybrid on your site. You have definitely peaked my curiosity here, but I need a little help.


Is anyone thinking about building Walsh drivers?

Hi Mapman,

I do agree with you, I love to listen to them too. However, as a designer and builder trying very hard to carry on the legacy of Lincoln Walsh, there is nothing quite like hearing one of our new designs roar to life and blow you away. It is a costly technology, but worth it in every way.

Wish we could go to the shows too,... but you know, spending more than $20K to attend and set up is just not cost effective for us. Rather spend that on a new design. The economy being what it is these days places a big burden on us and many others like us.

Still, you are welcome anytime.

BTW, do you remember the Ohm G? Our new TLS-4(IV) "DIY" driver and the new TLS-5(V), really go way beyond these old beauties. Drop me an email and I will send you some pics.

Hello Martykl,

No, you didn't miss any IQ test.

The TLS-4 and TLS-5 are new offerings for this year (2012) and our "IT Team" has not caught up with us yet. We are working on getting these items on our site but it does take time.

The TLS-4 is a DIY Walsh style driver that is very compact and covers the Tweeter/Midrange in a single driver. This is designed for those that want to build their own systems.

The TLS-5 is just completing the prototype phase, (with a few on order) and is a Full Range Tower System consisting of Two Walsh style drivers and a ("gag") crossover. (You guys know how much I hate crossovers, even if they are high quality.) This system has a much smaller footprint than our big floor standers. Range is 37 to 22 kHz, 3db down points.

You can see the TLS-4 on our virtual system thread under "My Walsh Dream" Ever Evolving category. For now, until our website is fully updated, you can contact me by email and ask for pics and info.
It's been 6 years since I've tinkered with building my own Walsh drivers. It seems like yesterday - the years do fly by. I was involved with the DIY Audio Forum then and my contributions to the thread start here:

Here's my old post with the parts and materials - then costing about $200!

Build your own Walsh loudspeaker for about $250 in parts and materials:



6.8 uf high pass capacitor (metalized polypropylene) to tweeter (

4 ohm power resistor in tweeter circuit.

Sonotube: nominal dia. = 12.5 inch height = 37 inch
Stuffing: acoustastuff ~50% of internal volume

This speaker glue has consistency of Elmer’s glue when wet, dries fairly quickly (water base) to form a clear and very flexible soft clear rubber with excellent damping characteristics.

Walsh Loudspeaker: two-way X-over first order (6dB/oct) high pass filter to tweeter at 8 kHz
Woofer – full range (no crossover)
Alignment: Acoustic suspension (Vb=2.5 cu. Ft; Qtc = .816; Fc = 49 Hz (-3dB))
Frequency Response: 49 - 20,000 Hertz (-3 db, +0db)
SPL: 89 dB/watt Max Power: ~100W

Illustration: Cone with felt damping applied with speaker repair glue.
Photos #1(schematic) and #2: woofer with felt dampers and felt variovent in dustcap. Variovent consists of ¾” dia. Hole cut into center of dustcap and hole covered with three laters of felt to provide resistive vent.
Photos 3-5: final loudspeaker.

Photos of the loudspeaker are posted at the forum link above. Now the purists will say that this is not a true Walsh because the cone angle does not provide for perfect phase-time alignment - I don't know. The thing is, the proof is in the listening and these loudspeakers sound so good. In fact, I'm still using them as the fronts for my dedicated home theatre. Guests are awestruck by the wrap around seamless sound field with such clarity (I am using side and rear conventional box speakers for the side and rear channels of course). My trusty Kinergetics bsc-100 stereo subwoofers are still performing yeoman's service after over 20 years (thank you Louis Nolemi). Now maybe my improvised Walsh has slight time-phase error, and perhaps passes a parallelogram rather than a square wave - I don't know. I've come to the opinion that the ear cannot hear small timing distortions but can hear frequency response-power response disparities. Anyway, for a few dollars and a few hours of labor, you can build these and I do predict you will like the sound a lot. In fact, these were so easy to build and the materials so inexpensive that I built three pairs and gave two pairs away to a neighbor and the church pastor.

Previous to this project, I built some true Walsh steep cone drivers. Yes, they sounded excellent. But, the time and effort needed to build them was great indeed. You can achieve excellent sound from properly selected conventional woofers using the modifications I listed above and careful cabinet alignment, with a lot less time and effort.

I visit Dale Harder's site periodically and his work is just gorgeous. I have had a hankering to buy a pair of his true Walsh F loudspeakers but I can't justify it at this time. I have my Walsh 5000s and I love them. I listen to them every night and pray that they never fail; because I've finally gotten by system to sound just right in my dedicated listening room.

While I would love to build another Walsh project with different higher quality drivers in mind, I will likely never get there. My medical practice is very busy and leaves little time left over for family. Also, after a 20 year hiatus, I picked up the french horn again 7 months ago. Practice is time consuming, exhausting and rebuilding one's performance and endurancer takes many months. My goal is to win a seat in amid level amateur orchestra. I want to get back on stage - I miss performance with a good symphony orchestra. I don't know if I'll get there but I will do my best and stick with it.
Hi Mamboni.

Great to hear from you. It's been a while!

Mamboni's writings on the various audio sites about the newer OHMs and Walsh drivers in general was largely responsible for my giving the latest generation of OHM Walsh speakers a try a few years back when I was in major upgrade mode.

I auditioned everything under the sun with price no object including large dynamic designs, the latest Maggies, Quad Electrostats, Magico, Gallo Refs, and others before deciding to try the newer OHMs in house first. It took me awhile as well to get everything dialed in just right in my main listening room as well but I am still so glad I did!

Mamboni's postings on the DIY site regarding DIY Walsh speakers are the most extensive, practical and best thought out technically that I am aware of. Anyone looking to DIY a pair of Walsh speakers should start there.