Brines M10-A10 MLT Speaker Build.

[iamnothim]

The planets have not aligned such that I can complete the three lower garage cabinets.  Instead….

I have decided to use a couple left over 3/4” pre-finished maple sheets to make a set of speakers.  This will be the build thread.

I have selected a design from Bob Brines.  Specifically the M10-A10 Mass-Loaded Transmission Line speakers.  $25.  They use a single Markaudio Alpair 10M driver.  $110 each.  NOTE:  I removed all the dimensions from Bob's document to protect his property.

I will select some veneers from Certainly Wood and have a PSA (peel-n-stick) backing applied from Superior Veneer.  I’ll probably go with a two-tone look to match the amp I built. Similar to the illustration except the sides will be tiger maple and the face and top will be a dark species.  Maybe dark cherry or a very dark walnut.  I do not like brown walnut.

Since I hate edge banding, I will probably sister an inch deep piece of 4/4 hardwood to the plywood edge using dominos.  This should make the recessed face come off much better than an edge band.  Then again, I may chicken out and build a flush box and cover with only one species of veneer.  Below is a picture of a friend's Linn subwoofer that I recovered with cherry PSA Veneer.
I’m thinking I’ll start working through the cut sheet tomorrow.  Stay tuned.

Luke

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[Gwerner]

Very cool project, looking forward to watching this one!

Was the amp a kit or a homebuild?

 

[iamnothim]

Very cool project, looking forward to watching this one!

Was the amp a kit or a homebuild?

I purchased a set of 6 boards  from Tom Christiansen and purchased the components from DigiKey and Mouser.  The power transfformer is a ClassisTone 40-18069.  The output transformers were custom wound by Jack Elliano at Electra-Print / Electra-Fidelity.  I designed the enclosure, top and back plates.  I used Illustrator to make the panel layout and had Aqua Tech cut them out from sheet bronze.  I am not an engineer,  I can barely remember how it works, but I'm pretty good at soldering.  These days I have to re-learn everything after two weeks.

Tom modified his design to support ECC88, USN-CEP 6922 receiver valves.  I like vintage glass.  I have a set of 1958 Amprex Bugle Boy "D" getters and a couple sets of 1964 Amprex USN-CEP 6922's.  The 300B power valves are JJ's.

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[tiralie]

Tom modified his design to support ECC88, USN-CEP 6922 receiver valves.  I like vintage glass.  I have a set of 1958 Amprex Bugle Boy "D" getters and a couple sets of 1964 Amprex USN-CEP 6922's.  The 300B power valves are JJ's.

It's all Greek to me, but I still find it fascinating.
Tim

 

[canadamike]

This has grabbed my attention, really looking forward to seeing your build!

BTW, your work bench turned out very nicely.

I built a number of projects through HeathKit when I was in high school, my mom still uses the first stereo I built. Would you mind sharing your rough cost estimate of the electronics and speaker components?

Thx Mike

 

[iamnothim]

It's all Greek to me, but I still find it fascinating.
Tim

What amazes me is getting incredible sound from 50 year old tubes (valves).  Wine for the ears.
I like to call tubes valves because the Brits invented them and that's what they called them.  A very appropriate name since they are truly valves for electrons.  Sadly replaced by the transistor.

 

[iamnothim]

This has grabbed my attention, really looking forward to seeing your build!

BTW, your work bench turned out very nicely.

I built a number of projects through HeathKit when I was in high school, my mom still uses the first stereo I built. Would you mind sharing your rough cost estimate of the electronics and speaker components?

Thx Mike

Hi Mike,

The speakers cost:
Two sheets of 3/4" baltic ply (domestic) $60 each
Hardwood for the plinth:  $50 est.
Two Markaudio drivers  $110 each
Misc wire, carpet spikes, and binding posts:  $50
Veneer  $125 - $225
Estimated total:  $565 to $665

Then there's the amp:
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[canadamike]

Hi iamnothim

Could I contact you off-line to get more information on your project? I am very keen to learn more details.

You seem to be a little more than your festool name...

Thanks, Mike

 

[iamnothim]

Could I contact you off-line to get more information on your project? I am very keen to learn more details.

shore nuff

You seem to be a little more than your festool name...
Thanks, Mike

My reputation predeceases me.

 

[iamnothim]

I picked up some curly soft maple for the edge trim and the plinths.
Tomorrow Ill order the veneer.
Curly maple for the sides and back and one of two Camphor Burls.  Either the red or greenish.
Tell me what you think.

I have decided not to have a PSA backing applied.  I'll use my veneer press and apply at least the front and top before assembly.
This makes the veneer thinner and the edges tight.  I also can't use PSA on burl like this.

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[Cort]

I have decided not to have a PSA backing applied.  I'll use my veneer press and apply at least the front and top before assembly.

I think you are wise to not use a PSA veneer.  I applied some PSA veneer, albeit from a different supplier, a few years ago, and the veneer is starting to lift at the edges.  Nice options on the burl veneer.  They will be quite beautiful speakers.

 

[Cheese]

Luke,

That Markaudio speaker is very interesting. How far down, say +-3 db, does it go?

Doesn't it make you wonder what the audio scene would be like today if Altec, Bozak, Klipsch and JBL had this type of technology available to them 50 years ago.

If I remember correctly, I think it was Altec Lansing that was a great pusher of coaxial loudspeakers.

I like your valve amp...reminds me of some old Mac and Audio Research gear I owned. Especially the Mac stuff where the valves would be presented very up-front and center stage. How much power does your amp put out?

I'm really interested in how these speakers turn out. This will be a fun build.

 

[iamnothim]

Luke,

That Markaudio speaker is very interesting. How far down, say +-3 db, does it go?

Doesn't it make you wonder what the audio scene would be like today if Altec, Bozak, Klipsch and JBL had this type of technology available to them 50 years ago.

If I remember correctly, I think it was Altec Lansing that was a great pusher of coaxial loudspeakers.

I like your valve amp...reminds me of some old Mac and Audio Research gear I owned. Especially the Mac stuff where the valves would be presented very up-front and center stage. How much power does your amp put out?

I'm really interested in how these speakers turn out. This will be a fun build.

I was afraid I'd get questions like this.  I'm a solder monkey.  Just like I'm a woodworking glue monkey.
I navigate audio stuff by braille.

Looking at the curve on the Alpair spec sheet it looks like they go to ~25Hz
What's interesting these days is how efficient the drivers are.  My 300B only puts out 10W into 8ohms.
I drove my Thiel CS1.5's nicely but I think it'll do better with these. 

I was tipped off to the whole MLT single driver speaker design by the gentleman that designed the DG 300B amp.  He's a sr. EE design engineer for Texas Instruments.  Tom really likes the Brines MLT design so that's why I'm going there.  A complete leap of faith.  Although Bob has a decrepit web site, buried there are equations and graphs that he and Tom banter about on acoustic forums.  Works for me.

My source is a Schiit Gungnir DAC that I feed 1T of .flac music.  I'm looking to go vinyl down the road after I save some more pennies.

EDIT:  Speakers are ordered.  Veneer tomorrow.  Then it's time for the parallel guides, extensions, and TS55
deja vu Mike

 

[Kev]

This thread tweaks my urge to dig out a relic I have tucked away .. A Thorens TD125 Mk2 with Shure SME3009 tone arm. The dturn table, arm, etc are in perfect condition, but the plinth needs love. I haven't spun any of my vinyl for many, many years .. though I'll still collect the odd one.

The tipping point is really the scarcity of spares - heart breaking if I put in the effort to bring it back to life and suddenly can't get a replacement belt or something.

Decisions ... [sad]

 

[canadamike]

Hi Luke,

Just posting this for the benefit of others on the veneering. Sounds like you are good to go with your process.

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I saw your post on veneering, I have done several kitchens in the past.

You likely know this already, but you don't need to use the same high
quality veneer on the insides, but it should be the same species of wood,
so your veneered panels are balanced. So curly maple on the show-side the
inside gets some low grade maple. I use Unibond 800, with the suitable
blocker to prevent bleed through for my veneering. Not sure what type of
press or equipment you have.

Mike

 

[iamnothim]

This thread tweaks my urge to dig out a relic I have tucked away .. A Thorens TD125 Mk2 with Shure SME3009 tone arm. The dturn table, arm, etc are in perfect condition, but the plinth needs love. I haven't spun any of my vinyl for many, many years .. though I'll still collect the odd one.

The tipping point is really the scarcity of spares - heart breaking if I put in the effort to bring it back to life and suddenly can't get a replacement belt or something.

Decisions ... [sad]

DO IT !!!!

It's tragic not to.  Life is too short to listen to processed music!

 

[225]

What are the speakers you are building comparable to? I have a BIC America surround sound system that I pieced together. And I want to either put the speakers I have now in hardwood cases or build my own.

 

[Cheese]

This thread tweaks my urge to dig out a relic I have tucked away .. A Thorens TD125 Mk2 with Shure SME3009 tone arm. The dturn table, arm, etc are in perfect condition, but the plinth needs love.
The tipping point is really the scarcity of spares - heart breaking if I put in the effort to bring it back to life and suddenly can't get a replacement belt or something

[member=13058]Kev[/member]
Does this look familiar....

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This one's been quietly resting in the back of the closet for the last 45 years. She's a little dusty but certainly worthy of a modern day cartridge.

 

[tjbnwi]

Luke,

If you need a high quality turn table I can send you one. Just pay the shipping [laughing]

Tom

 

[tjbnwi]

This one is not mine, I just made the plinth.

Tom