2018 TL build

jceason

I've been meaning to become more active on here with everyone over the past...........ugh year or so.  How the time goes by.  I figured no better way to jump in than to show off for the first time my first full speaker project.  I re-purposed an old pair of DCM TF-500's that had seen better days back in 2017 and brought them to the 2017 Meniscus get-together, meeting several great guys on here.  I decided 2018 would be the year I build a pair from the ground up.  I have always been interested in the transmission line enclosure and how they sounded.  After months of research and educating myself on the TL principals and benefits and short comings of the design I decided a MTM layout would be the best way to start.  I am fond of large, furniture grade speakers that have a presence in the rooms they are set up in.  The trend I have noticed over the last couple of years are small, high performance book shelf speakers, of which I have had a few over the years, but my heart loves big tower speakers that have equally big sound and look great doing it.  I settled on Meniscus Audio's Eclipse W6520R-4 woofers and SB Acoustics SB29RDAC tweeters.  I used .75" mdf for the cabinet and internal baffle and 1.25" Ambrosia Maple for the baffle.  Once the enclosures were built I spend many hours with Matt at Meniscus Audio here in Grand Rapids designing and tweaking the cross-overs.  I was surprising how much time and parts swapping it took to dial in the cross-overs.  I was quite frustrated at one point at how poorly they were performing versus expectations.  On a thought Matt swapped out their Cebo caps we had been using and put in Clarity caps.......What a night and day difference that made.  The woofers are 4ohm and wired in series presenting a comfortable 8ish ohm load at the sacrifice of efficiency.  

Here is the finished product:






I began the project in February and finished in July.  I wasn't able to attend the Iowa DIY and missed the Meniscus get together which was a bummer.  I was hoping to get some feedback and suggestions from everyone.  I enjoyed designing and building these and love how they sound.  They are a big improvement over my DCM project which I felt sounded wonderful.  I learned a lot on crossover design and hope to get measurement equipment in the future.  Matt at Meniscus Audio was an invaluable resource and helped get this project to fruition.  Hopefully there's many more projects to come!  

GeoffMillar

No idea how they sound, of course but the cabinets are beautiful, especially how you routed the driver holes on hardwood. Great job.

Cheers

Geoff

Wolf

You could bring them to InDIYana in a few months...

They look great!

hifiside

Nice looking towers! I like the marble look. Plastic bag method?

tajanes

great looking speakers, the Ambrosia Maple baffles with the 'textured' dark boxes very cool
I second 'bring them to InDIYana"...

rjj45

Very nice work! 
How did you sim the TL? Looks like a TQWT.
I gotta say, though, tuning a crossover by ear is not my idea of fun. 
A cheap(ish) PE microphone and ARTA will take you a long way, at peanuts expense.

jceason

"Nice looking towers! I like the marble look. Plastic bag method?"

We tried sponging to start with but found that using a modified rag roll technique gave us the best look.  I rolled the basecoat to give a textured finish.  My original thought was dark edging with a lighter middle on each panel but making that happen and look unique just wasn't working.  I should have used plastic bags due to the lint left behind from the old t-shirts I used.  The look has grown on me over the last 6 months but wasn't the image I had in my minds eye...LOL

jceason

"How did you sim the TL? Looks like a TQWT.
I gotta say, though, tuning a crossover by ear is not my idea of fun."

They are a taped line design.  This raises the F3 but increase efficiency while helping control line resonances.  There are so many articles and formulas out there it was incredibly difficult to find clear, defined answers to questions.  I'd have to go back through my notes and find which site I used for calculators.  I chose a basic calculator for line length based on the driver parameters and cross section.  There are formulas for the formulas it seems like.  The calculators I used are on the MH Audio page.  There is so much technical data out there that I went with the simplest calculators to start with and went for it.  Line damping was almost as frustrating as tweaking the crossover.  I made the bases removable so I can keep adjusting and trying different materials.

dynamo

Beautiful! Nice driver selection too. I haven’t used them but I think those Eclipse woofers are beautiful. They just have a classic business like appearance, like the scans in the older ProAc speakers.

Ive also really been wanting to try those CSA caps. I really like the cheaper PX line. They have a touch of warmth or richness to them (my subjective opinion of course).

jceason

I completely agree, their appearance was a big influence as their specs.  It seems not a day goes by that I don't look at these towers and smile.  The Eclipse driver is an agile and detailed driver that looks cool and capable.  I have been considering redoing the cabinets to more closely match the charcoal color of the drivers.

I have traditionally used Solen and Audyn caps on previous builds.  It was a big jump in investment going to the CSA caps but I couldn't ignore the huge benefit to the sound quality they added.  Going from a $6 cap to a $19 cap is a big pill to swallow but I feel they are worth every dollar I spent.  Very smooth and open.  I had big hopes for Meniscus's Cebo caps but they didn't mesh well with the SB tweeter.

Thank you for your kind words!