Levels of insanity.

Last nights project from the scrap heap was another "quickie" that we discussed a while ago and I purchased the materials for.   Jon at Lowther America asked how a copper washer fitted to a Lowther phase plug would work.  While theory abounds, there is no better option than to get your hands dirty and give it a try so I took a half hour off and played.  Unfortunately I only could find one of the appropriate plugs and more are on the way so listening tests on the the effect with the Lowther field coil will have to wait.

From Lowthers to another Old English standard.

Oops... that was the milwaukee standard for insanity...

The phase plug wasn't even close to insanity of some of the people we call "family".  Back in July one of the family pushed the 301 envelope a bit with a solid brass platter for his 301.

Well,  Lets just say the results were promising enough for him to "kick it up a notch" and the results are not for those with a weak stomach.

Yes,  that is a solid Brass 301 deck + platter (with a 401 motor) and the insane thing is he is not done yet.  The bearing housing is next.  If all goes well, there will be a "DIY" room at the Capital Audiofest this year and everyone will be able to hear it against a stock 301 on some quads and be their own judge of what is insane.

I can't wait to hear it!

Phase Plug Tweeter...

Will someone please take me up on this one??? I have paraded the idea around for years. To me, it seems obvious. We love these giant Le Cleac'h front horns with Lowthers, but always have the issue of where to put the tweeter.

Luckily, we have been unanimous in the preference of the large wooden "lightbulb" phase plug. I think that comparison was both first done, and put to rest at VSAC 2003. This phase plug is *huge*... and there is room to sneak a tweeter inside..



granted, the tweeter needs to be at least 105dB.. and 108 is better, so maybe that was the catch... but I now have an answer... there is a new B&C... a ring radiator.. and that just beautiful sounding mylar diaphragm... clean, clear.. and with the inside slug of neodymium, it is both small enough and efficient enough for the application...



I suppose with the new batch of Le Cleac'h Lowther front horns coming, I will finally get to try this one... woo hoo!

Me

Lowther Phase Plug Tweeters Pt. III

I guess since I have the metal lathe and the Lowthers up and running, this project has shifted to me, yet I want to be clear the original concept is JJ's.   I hinted to the progress in the Emancipation Day entry, and the Brown Truck brought a brown box with the last needed part some 4 X 0.7 mm threaded studs.

I didn't do them exactly to JJ's drawigns trying to keep it as close as possible to a typical doorknob plug.  I installed them and put on some tunes as I wired them up.  With them in place and not wired the highs were severely truncated but they quickly came back when I connected the tweeter through a 1 mic series cap.  I only had enough time to get through 1 album side and I definitely need to play with phasing and crossover frequency but things are looking good!

As a proof of concept, there is a lot of promise and the second run through gave us a lot direction for the MK III variation.  The first experiment happened with the use of a single drywall screw last May in Texas at the LSAF and quickly taught us that the physical distance between the voice coils need to be set to the crossover frequency.  We also have a few other tricks to try out on the next revision so stay tuned to this work in progress.

Phase plug tweeters, PT II...

The tweeter that I am using for the phase plug tweeter that goes in the Lowther front horn is finally back in stock. They have been back ordered for nearly a year. I am not sure how long they will available, so speak up if you want one of these. I will turn them from maple or mahogany, your choice. Lead-outs will be 30 gauge magnet wire. In Dallas we rolled these in with a very small cap - 0.33uF - and it blended well. Quite a few people remarked on the clean treble. Pessetto was as effusive as an engineer can be. (I am an engineer as well and am therefore qualified to make fun of him).


This is such a time consuming small job that I don't really want to take any future single orders for these. I will make a group of them now, and then it will likely be a while before any are made again. Pricing will be between $750 and $1250, depending on how many orders come in...

Thanks everyone!

The Voigt Legacy...

Yeah, it is fashionable to bad mouth Lowthers... I get it... measure one straight on in an open baffle and it is rough... but what if I presented it a different way? how could you make the best sound with these? Can you admire what they do well (and those things are phenomenal) and live with what is not perfect? That mindset just might lead to happiness for a lot of people....

so let's look at that weird name associated with Lowther and see if we can learn anything... what did he build?


yeah, a front horn! smart man... I bet this thing sounds fabulous... (I heard teh Voigt museum does not have one of these... I found it in Hope, AR!)


look at those smooth horn curves ending in ninety degrees... even a small roundover on the very edge.. diffraction, be gone! tractrix flare... nice.....

so what else did he build? well, a corner horn.. with reflectors to get the highs out... a very well thought out cabinet... I bet one of these in the corner sounded pretty darn good...


highs were bumped out by using a small deflector.. check it out...


and the drivers from that era....


Modern Lowthers are very different than the old models. Gone is the heavy lacquered cone.. the whizzer now has a roll on it.. the light bulb phase plug has been lost... so do not believe people when they say Lowther has not changed with the times - they have... there is even an outfit making new field coils.. designed with finite element computer modeling... (very tongue in cheek)...


the newer cones are better for all of these direct radiating cabinets and back loaded horns.. the rolled whizzer helps control what the horn's air load used to... put them in an appropriate room... set them up with care.. get toe-in just right.. turn off the lights.. and you can get visiting musicians to your room.. how do I know this? well, once upon a time when I was too young to know any better, Jon Ver Halen talked me into bringing a single ended, no feedback amplifier to a Stereophile show to pair with, gulp, Lowther Medallions... we set them up by ear... and then Wally came in... took teh best seat.. wouldn't leave.. kept spinning record after record... so then he came back teh next day with measurement gear... we were +/- 3dB from 20 to 20k by cheating with a sub below 45Hz... pretty amazing for a single voice coil...


and I guess that is why I defend Lowther to the end... pretty tough to get that performance from a single voice coil of any sort.. especially at high SPL on a five watt single ended amp...

Peace,
Me