[Scott F.]

Continuing our experimentation of Lowther's in an open baffle, last night Blackmore (Mark) brought over his version of the baffle-less Lowther. Mark likes to call these Lowther Music Posts. Here is a quick pic of Mark's Lowther PM6As sitting next to my PM2As.





Basically what Mark did was use a mortar (as in mortar and pestal) to secure the driver and then he mounted the mortar on top of a (sheet) music stand. Its about as simple a concept as you could imagine. Of course, bass augmentation is required. At my place we are using the 15" Altec 416s but at his place he is using the bottom half of his Innersound panels which sport a vented 10".







Unfortunately my Pioneer SF-850 crossover is down for service so we couldn't adjust the XO frequency up to where it needed to be (~400Hz). We were using a prototype XO in its stead. This particular XO has a high point XO at 150Hz which works great with my baffles but leaves the Music Posts a tad thin sounding but there was no mistaking our two versions (visions) came from the same Lowther lineage. Mark is still running in his pair of PM6As so they had some zing at times but I think he's onto something that should work really well with the right XO.

After setting up both sets of speakers, something kept gnawing at me most of the night about how familiar this scene looked



Then I figured it out.....



It was Eskimo by the Residents 



Only a couple of guys have heard my system in the past couple of weeks since I've finalized a few major tweaks. You guys will all get to hear it at our Christmas in September annual bash (watch for that post in the next day or so). I won't say to much other than to say be prepared. It doesn't sound anything like it used to (SteveK, its changed pretty drastically since you were last out). I'll leave any other comments to Mark and Chris (MerRev) since they've heard it.

Lets see, so far I've got Mark (Blackmore), Chris (MerRev) and now Ron (Sarmik) drinking the Koolaid  ...yep, Ron just bought a pair of PM6Ts (the Ticonal magnets) and is getting ready to construct his Lowther Open Baffles. There is absolutely something to this.

Anyway, had loads of fun last night. I even got to turn Mark onto Bloodrock DOA 

[Bob in St. Louis]

Hey that's cool!  aa
I can't wait until September. I'll be there "with bells on", very eager to hear the new rig. I'm starting to have withdraw symptoms not having seen you fellas in so long.

I do know of another STL(ian) that's wanting some Lowthers in a baffle. Once I recuperate I'll be building them (which will be very soon in case you're reading).

Mark, Congrats on the new sound. That's very creative with the mortar and music stand!

Bob

[mark@marktwain]

Scott,
Yeah you got me sippin the Koolaid too buddy. I have a pair of pm2c's although their still in their boxes awaiting me building baffles. I can't wait for the bash. Your rig sounds better every time I get to hear it.

I did finally get my monoblocks built though, heres a picky of one of them.


Mark

[Blackmore]

Bloodrock DOA was great.  It is the dirtiest, nastiest record in Scott's collection.  I think some of it might have been body fluids from the wreck (DOA)    And did we bother to clean it?  With a RCM 3 feet from the listening spot?   Hell, no!!   The music just emerged from underneath the lightning storm of snaps, crackles and pops.  Best of the night was "Eskimo"  I have to find that recording.  My LMP (Lowther Music Posts) certainly need more time for break-in and they sure don't work all the way down to 150 Hz, but it was a fun listen.  I won't be giving up my stats anytime soon, but the LMP is a nice alternative for the listening room that only takes a moment or two to install. 

Thanks again Scott.  Had a great time talking audio and listening to old rock n roll way too loud. I think I've recovered.  I got the Jantzen caps in the mail today, so I'll do a little work to make the LMPs passive and the bass bins active.  Maybe that will help with the hiss at home.

Marktwain!  Miss you, man.  Nice work on the monoblocks.  Very nice work.  See you in September. 

Oh, one more thing.  Scott's system has really changed since I heard it last.  The prototype crossover has done the trick.  Also the DRD amps are back in action and I've always liked them.
Much smoother, less (almost none) noise, much better bass from the improved Altec cabinets, etc.  You'll smile when you hear it. 

[Scott F.]

Way cool build on the 2A3 You'll definitely have to bring it down in September.

That's right, I forgot you picked up some Lowthers too. Thats too funny. That makes 5 of us doing Lowther OBs. Then we've got Alex wanting to do the same with his which actually makes 6. Bob, I assume you were talking about Alex  I almost counted him in above but didn't because I wasn't sure if he still planned doing the project. He'll definitely need some woofers and an active crossover.

Sometime really soon I'll have an article up at ETM about the Lowther journey. In it I'll post the dimensions to the baffle in case anyone wants to try it.

So Mark, did you buy potted transformers and sandblast them or did you pot them yourself?

Scott,
Yeah you got me sippin the Koolaid too buddy. I have a pair of pm2c's although their still in their boxes awaiting me building baffles. I can't wait for the bash. Your rig sounds better every time I get to hear it.

I did finally get my monoblocks built though, heres a picky of one of them.


Mark

[BPT]

MarK:
The Music Posts are way cool and must throw an incredible soundstage. Now add a nice OB woofer and your cookin' (where's Bob). My latest 6' line source OBs are still in baffle construction, but are looking good. With 20 drivers per side, they will kick some serious dB butt.

Other Mark:
Very nice amps, great job.

Scott:
Can't wait to hear'em with your latest tweaks.

Chris H.

[steve k]

Mark:
Beautiful work on that amp! I love the curved front.
Scott:
All you guys need is Chris's pair and you'd have Lowther Tympani! Can't wait to hear both your systems. Nice work. Mortar huh?
steve

[Sarmck]

Hey...no fair guys...I wanna play too.     Can't wait till I receive shipment on the Lowthers.

mark@marktwain,
Very nice build on the 2A3 amps.  Bet they sound just as beautiful too.

Ron

[mark@marktwain]

Hi guys,

The amps are 3-stage 76 - 6sn7 - final, which can be a 45, 2a3 or 300b. They are the je-labs circuit with different operating points and a different power supply. Power supply is the Angela tranx, 5v3a, L-C-L-C-L-C with ASC 50uf film/oil caps. All bypass caps are also film. Coupling cap is russian teflon. All wire is Kimber TCSS triple runs. Output tranx is the diyhifisupply universal.  Resistors are Kiwame except for a few Mills.

I'm now running TJ 2a3 globe mesh plates. WOW what a difference. I'm diggin them a lot, pretty sweet on the Fostex's. I don't think I'll be able to settle for any less than the TJ's now. I also have a pair of TJ 300b globe mesh plates and I want to get a pair of 45 meshies too.

I was planning to mount a meter recessed in the slanted part of the front but decided not to. The transformer covers are just covers and are removable, their not potted. Here's a belly shot.

Scott, I'll bring them to the bash if you or someone else will carry them down to the man cave. They weigh about 40 pounds each!

[G]

Scott,
Yeah you got me sippin the Koolaid too buddy. I have a pair of pm2c's although their still in their boxes awaiting me building baffles. I can't wait for the bash. Your rig sounds better every time I get to hear it.

I did finally get my monoblocks built though, heres a picky of one of them.


Mark

Jesus but that is nice! Good stuff!

[G]

Hi guys,

The amps are 3-stage 76 - 6sn7 - final, which can be a 45, 2a3 or 300b. They are the je-labs circuit with different operating points and a different power supply. Power supply is the Angela tranx, 5v3a, L-C-L-C-L-C with ASC 50uf film/oil caps. All bypass caps are also film. Coupling cap is russian teflon. All wire is Kimber TCSS triple runs. Output tranx is the diyhifisupply universal.  Resistors are Kiwame except for a few Mills.

I'm now running TJ 2a3 globe mesh plates. WOW what a difference. I'm diggin them a lot, pretty sweet on the Fostex's. I don't think I'll be able to settle for any less than the TJ's now. I also have a pair of TJ 300b globe mesh plates and I want to get a pair of 45 meshies too.

I was planning to mount a meter recessed in the slanted part of the front but decided not to. The transformer covers are just covers and are removable, their not potted. Here's a belly shot.

Scott, I'll bring them to the bash if you or someone else will carry them down to the man cave. They weigh about 40 pounds each!

Nice work. Not as good as mine of course but.............................

[lonewolfny42]

Bloodrock DOA was great.  It is the dirtiest, nastiest record in Scott's collection.  I think some of it might have been body fluids from the wreck (DOA)    And did we bother to clean it?  With a RCM 3 feet from the listening spot?   Hell, no!!   The music just emerged from underneath the lightning storm of snaps, crackles and pops. 

http://www.youtube.com/watch?v=A1PLT0GljPA

Nice work on those Lowthers....and one sweet looking amp.

Thanks for the photo's....enjoy !!!

[Scott F.]

I was hoping you were going to post some porn shots of your new amps.  When I looked at it yesterday, I thought I saw a third gain stage using a triode. I wasn't sure but it looked like a 26/27. I was going to post the question but got busy at the office.

So is the 76 nice and quiet? I know the 26s can be noisy to the point you have to do a battery power supply....and dude, you did a mercury vapor rectifier  Is that a filement delay switch on the front panel for the 76?

Like G said, I'm thoroughly impressed. I bet that power supply has zero ripple with all those stages. Gotta be super quiet.

The amps are 3-stage 76 - 6sn7 - final, which can be a 45, 2a3 or 300b. They are the je-labs circuit with different operating points and a different power supply. Power supply is the Angela tranx, 5v3a, L-C-L-C-L-C with ASC 50uf film/oil caps. All bypass caps are also film. Coupling cap is russian teflon. All wire is Kimber TCSS triple runs. Output tranx is the diyhifisupply universal.  Resistors are Kiwame except for a few Mills.

Scott, I'll bring them to the bash if you or someone else will carry them down to the man cave. They weigh about 40 pounds each!

We'll get somebody to carry them downstairs. Unfortunately I won't be able to do it either. I had major abdominal surgery earlier this year. Sometime in the last month I herniated all the muscles that were sewn back together at the incision so now I've got this big bulge where my intestines are poking out past my stomach muscles. I think it was when I started working out again. Its pretty disgusting looking....doesn't hurt but it sure is weird. I going to end up having to go back in and get all the muscles reattached sometime soon. Who knows, maybe its Gods way of telling me I need to be a fat, bald old man. That or Karmic retribution for something stupid I did in my past...then again, isn't stupidity forgivable?...guess not.

Hopefully, this won't delay the Christmas in September bash. If so, it shouldn't be for more than a week or two depending when I get cut on again. Getting old isn't for sissy's.



Wolfy, nice touch with the Walter Cronkite tribute as your avatar 

[mark@marktwain]

I've been meaning to post some pics for quite a while but have been busy (I'm installing new windows in my house, 23 of them). I wanted to take some new pics with both amps together sporting the sexy TJ globe meshies but just can't seem to get it done. The 76 seems pretty quiet in this application at least the ones I have are. I can use a 37 in it's place also. I'm using ac on all the tube filaments. There is a little hum which you can hear if you are a couple feet from the speaker but I can't hear it from the sweet spot which is 15 feet away.

Nope, no mercury rectifier. The 5v3a is similar to the 5u4gb with about 10v less voltage drop and said to sound better according to my mentor.

The switch on top is to switch in parallel cathode resistors so I can run either a 45, 2a3 or 300b with optimum operating points. I used the terminal strips on the power transformer because it has multiple HV taps which I can swap for the B+. I also used a terminal strip for the output tranx as it has multiple taps too 2.5k, 3.5k, 5k and 7.5k at 2, 4 ,8 or 16 ohm.

Another thing I did which you may fine interesting is I drilled a hole through the binding posts and ran the wire through the post and soldered it at the point where the speaker wire attaches to limit the signal from having to pass through the mass of brass. There's a tongue twister for ya.

Oh, the other amp is already finished. I'll plan on bringing them to the bash then. Maybe I'll bring my preamp also it's a mapletree 5b clone.

Mark

[wedweb]

http://www.impactlab.com/2009/06/22/ultimate-see-through-speakers/

Scott, someone else came up with a different design using Plexiglas and lowthers....