Pure Audio Project Trio15TB Home Build

jonbuilds · « **Reply #20 on:** 4 Sep 2019, 01:14 am »

Quote from: Russell Dawkins on 3 Sep 2019, 07:48 pm

I'm curious how the 1808 compares with the 1772
https://www.parts-express.com/tang-band-w8-1772-8-neodymium-full-range-driver--264-893

On the surface they look similar, but the 1808 has more excursion and is 1 dB less sensitive.

I'm a little out of my pay grade here, but I assume that the higher Qts of the 1808 is more desirable for OB application, among other less objective (i.e. listening) criteria. Personally, I relied on the heavy lifting that PAP did in designing the speaker. I'm guessing they considered most every imaginable driver in the price range of the 1808, and they don't see any income from the purchase of that particular part. Even now I believe the PAP website offers the Trio15TB without the "TB" part, and Ze'ev directed me to Parts Express for the 1808 purchase when I got my Neo15" drivers from PAP. I wouldn't even consider substituting drivers on the build - these things sound great, and PAP did all the testing!!

jonbuilds · « **Reply #21 on:** 4 Sep 2019, 05:40 am »

Hardware fit up. After wrangling a number of ideas, I decided to use off-the-shelf Unistrut and Home Depot equivalent Superstrut hardware. The support frame needed to be rigid, adjustable, and not require any complex fabrication since I don't have a welder, vice, press, break, or even mildly precise cutting tools. I had a sawzall, a drill, some wrenches and other simple hand tools, a dremel, and some time...

V-drill guide & drill stop from Rockler:

Budget edge cleanup with a larger bit

Driving the machine thread inserts

Completed machine thread steel insert

Rubber baby buggy bumpers. I mean rubber fender washers to prevent passive mechanical buzzzies between baffle and strut

First strut dry fit

First strut anchored

Layout holes for next set of inserts

two struts in!

First leg. Used a flat splice and bent to approximate angle needed. Had to think REALLY HARD about the order of operations to bolt it together....

First leg, different angle.

Two legs, about ready to stand up

Looks like a thing!

Definitely a thing!

oskar · « **Reply #22 on:** 4 Sep 2019, 01:03 pm »

This is great.
Good to see a build so well documented.

jonbuilds · « **Reply #23 on:** 5 Sep 2019, 02:25 am »

Speaker fit-up.

Baffle with legs only next to Tekton OB Sigma

Closeup of finished corner. I think I stopped sanding and finishing at this point.

Speaker dry fit during baffle prep

Speakers in finished baffle for the first time

Loaded baffle standing on its own two legs, next to Tekton OB Sigma

Desperate to hear it, throwing some cabling together. You know how it is...

Coming up soon, I decide I really need a base under these....

Woodsage · « **Reply #24 on:** 9 Oct 2019, 03:03 am »

Beautiful job Jon, thanks for sharing.

FullRangeMan · « **Reply #25 on:** 10 Oct 2019, 02:00 am »

It was serial connected, do you can post the woofer/mid/xover schema?

jonbuilds · « **Reply #26 on:** 10 Oct 2019, 03:22 am »

Quote from: jonbuilds on 1 Sep 2019, 11:50 pm

Earlier this year, with personal input and OB-A15Neo 15" drivers from Pure Audio Project (thank you, Ze'ev!), terminals and TB1808 from Parts Express, and about 10 Home Depot runs, I finished building a slight variant of the PAP Trio15TB speakers.

I will add to this as my first ever build thread, as I sort through the pics I took during the process. I was not terribly disciplined about documenting it, but will gladly answer any questions based on what I did/learned.

Base under construction

More base

Edgy base

Baffle on base

Can you feel the base

Back base

First full operation with the bases installed. Terminals, base finishing remain.

jonbuilds · « **Reply #27 on:** 10 Oct 2019, 03:34 am »

Quote from: FullRangeMan on 10 Oct 2019, 02:00 am

It was serial connected, do you can post the woofer/mid/xover schema?

I promise I'll sketch a schematic at some point, but here's a narrative version: No passive crossovers. Each speaker has two 8 Ohm 15" drivers wired in parallel to one amplifier channel; one 8" driver wired to a separate amp channel on a separate amp. In addition I have separate subs that I use in conjunction with the PAP design Trio 15TB speakers.

Signal from the source is controlled via a passive preamp, which passes signal to an active 3-way crossover, which provides stereo output to low-pass <40Hz amps on subs; mid-pass 40 - 450Hz amp to 15" parallel drivers each channel; high-pass >450Hz amp to 8" drivers, this amp is a Nelson-Pass ACA 1.6 that I build earlier this year. (Separate thread at some point...)

FullRangeMan · « **Reply #28 on:** 10 Oct 2019, 03:39 am »

Quote from: jonbuilds on 10 Oct 2019, 03:34 am

I promise I'll sketch a schematic at some point, but here's a narrative version: No passive crossovers. Each speaker has two 8 Ohm 15" drivers wired in parallel to one amplifier channel; one 8" driver wired to a separate amp channel on a separate amp. In addition I have separate subs that I use in conjunction with the PAP design Trio 15TB speakers.

Signal from the source is controlled via a passive preamp, which passes signal to an active 3-way crossover, which provides stereo output to low-pass <40Hz amps on subs; mid-pass 40 - 450Hz amp to 15" parallel drivers each channel; high-pass >450Hz amp to 8" drivers, this amp is a Nelson-Pass ACA 1.6 that I build earlier this year. (Separate thread at some point...)

Nice, thanks for inform

kheidenr · « **Reply #29 on:** 8 Nov 2019, 06:22 pm »

Nice job. I am working on an open baffle style project right now using Zenith Alnico drivers at the moment. I am considering going active as well once if I decide I need helper woofers below 30hz or not. I was looking at the Sublime Active Crossover - what do you think of it? And how did you determine your crossover points?

kheidenr · « **Reply #30 on:** 8 Nov 2019, 06:27 pm »

I'm also very curious how your DIY speakers compare sonically to the Tektons. Thoughts?

jonbuilds · « **Reply #31 on:** 11 Nov 2019, 01:58 am »

Quote from: kheidenr on 8 Nov 2019, 06:22 pm

Nice job. I am working on an open baffle style project right now using Zenith Alnico drivers at the moment. I am considering going active as well once if I decide I need helper woofers below 30hz or not. I was looking at the Sublime Active Crossover - what do you think of it? And how did you determine your crossover points?

I liked the Sublime crossover and actually wrote a "consumer review" for it, it's on their webpage, titled "SERIOUS-MINDED BUILD, FUNCTION, AND SOUND" https://sublimeacoustic.com/products/k231-stereo-3-way-active-crossover

Crossover points were based on input from Ze'ev at PAP. Good luck with your build!

jonbuilds · « **Reply #32 on:** 11 Nov 2019, 02:06 am »

Quote from: kheidenr on 8 Nov 2019, 06:27 pm

I'm also very curious how your DIY speakers compare sonically to the Tektons. Thoughts?

I've had a couple of different Tekton Design speakers, but assuming you're referring to the OB Sigmas - I like the Sigmas. They opened my eyes to the possibilities of OB designs. The PAP design, in my opinion, sounds fuller, richer, more dynamic (faster?), a little less "squawky" but please understand this perception is based on a lot of side-by-side comparison. The Tekton OB is a an excellent sounding speaker. Also note I do not know how the PAPs sound with the passive crossover options they offer. Frankly, I'd like to try them, but I have to choose my equipment purchases carefully, I can only really afford about one per year, and right now I'm angling toward upgrading the Tang Band drivers to Voxativs - a pricey upgrade...

Russell Dawkins · « **Reply #33 on:** 11 Nov 2019, 06:13 am »

Quote from: jonbuilds on 11 Nov 2019, 02:06 am

Frankly, I'd like to try them, but I have to choose my equipment purchases carefully, I can only really afford about one per year, and right now I'm angling toward upgrading the Tang Band drivers to Voxativs - a pricey upgrade...

Have you included the Cube audio drivers in your comparison? I saw a comparison with, amongst others, the Voxativs in a Pure Audio project-type open baffle arrangement and the Cube came out on top. I can't find that comparison (it was in Russian, by the way), but here is another comparison with a Voxative.
http://hifiknights.com/reviews/speakers/cube-audio-magus/
The Cubes aren't cheap, but they are cheaper than Voxativ, I believe.
https://www.cubeaudio.eu/

jonbuilds · « **Reply #34 on:** 8 Dec 2019, 12:15 am »

Quote from: Russell Dawkins on 11 Nov 2019, 06:13 am

Have you included the Cube audio drivers in your comparison?
https://www.cubeaudio.eu/

Good tip, I hadn't considered the Cube Audio product. I poked around a bit and am still inclined toward the Voxativs, but whatever I do will have to wait until something comes up on the 2nd-hand market in this regard. I just can't justify the upgrade cost at new retail pricing! Also, I'm starting to feel the itch to build a couple of Mr. Linkwitz's designs, starting with the LX Mini. That may take precedent over the holiday break that I am definitely taking...

Russell Dawkins · « **Reply #35 on:** 8 Dec 2019, 01:05 am »

I also wonder how the Lii Crystal 10s
https://www.audiocircle.com/index.php?topic=165135.0
would fare in the company of the likes of Cube, Voxative and Tang Bands.

Too bad there isn't a neighbourhood Wide Band Drivers 'R' Us store in bricks and mortar to hang out in to listen and compare, but I guess that would be in an alternate universe!

Bumpy · « **Reply #36 on:** 11 Dec 2019, 08:27 pm »

Great build. If it was me I would get rid of the gap below the baffle. In reality the floor extends the baffle for the bass frequencies. The gap is a window that allows some bass to short circuit the baffle, causing cancellations.

FullRangeMan · « **Reply #37 on:** 11 Dec 2019, 09:28 pm »

Quote from: Bumpy on 11 Dec 2019, 08:27 pm

Great build. If it was me I would get rid of the gap below the baffle. In reality the floor extends the baffle for the bass frequencies. The gap is a window that allows some bass to short circuit the baffle, causing cancellations.

Correct.

matevana · « **Reply #38 on:** 13 Dec 2019, 06:13 pm »

The shelving standards that you are using as rear legs may have a tendency to resonate at certain frequencies. If this occurs you can try to fabricate a brace about one third of the way up (or down) so you have more then just the two end points of attachment. Nice job btw.

apple2k · « **Reply #39 on:** 15 Dec 2019, 07:06 pm »

What a great project, how do you like that coax driver? I know some love it and some feel it does not have a very smooth frequency response.