Core 2-Way - Build Tread

[MrkCrwly]

Re: Core 2-Way - Build Tread

Mark,
I'm really, really, impressed with your wood-working skills, your artistic creativity, and the ingenuity evident everywhere throughout this build. Very nice work. I picked up a bunch of tips -- thanks for taking the time to document your build. You are a true speaker building artist..

Grasshopper


I'd love to hear your listening impressions...

Thank you. High praise coming from you. I hope to be listening to them in the next day or so.
You should put a link to your TriTrix build in your signature. Now that is a build thread. http://techtalk.parts-express.com/sh...d.php?t=222519

[MrkCrwly]

Re: Core 2-Way - Build Tread

I stained all of the wood and coated with about 5 coats of gloss wipe on poly. The feet are beech b-lls (dang censor) painted flat black and secured with 2" screws with head cut off to thread into the base.









The ports have been cut to allow flexibility from 2 1/2" to about 4" or so.

[MrkCrwly]

Re: Core 2-Way - Build Tread

[ATTACH]13806[/ATTACH]
Kind of a shame that no one will see the bottom. To get the cabinet to sit on all 4 feet, I taped sandpaper to my table saw top and flattened the bottom of the b a l l s.
[ATTACH]13807[/ATTACH]

[ATTACH]13808[/ATTACH]
The only thing I have left to construct is the walnut accent strip that is applied on top of this ledge.
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The solid oak top and bottom are attached to the cabinet with 4 screws each.

[Paul Carmody]

Re: Core 2-Way - Build Tread

That quarter-sawn white oak is looking great!! I'm going to be using some again on another build.

[Soundslike]

Re: Core 2-Way - Build Tread

Very nice. I too love the quarter-sawn oak. Your design has a classic look to it, with modern touches. Great looking, and surely this design will have a very high SAF rating.

[fastbike1]

Re: Core 2-Way - Build Tread

Paul / Mark,

When I model the box in Jeff's Woofer Box, I get extremely high port velocity.
I have a 30 liter next box 2x3.5 vent whixh tunes the box to 38Hz. Using Zaph's TS params. Response pretty flat. 102dB @30 watts F3/F10 35/29, but port velocity is 39 m/s>

What did I miss?

Hmm... didn't realize I had changed the bass tuning. Geez, you guys are always pointing out my mistakes--you're like my students! ;)

I looked back over the simulations in Unibox. They're both OK, actually. 2.5" long will give a hint more low end boost, where the 3.5" is maybe just a bit rolled off. The difference is pretty slight, though. Do you have any way of trying both lengths, Mark?

[Paul Carmody]

Re: Core 2-Way - Build Tread

When I model the box in Jeff's Woofer Box, I get extremely high port velocity.
I have a 30 liter next box 2x3.5 vent whixh tunes the box to 38Hz. Using Zaph's TS params. Response pretty flat. 102dB @30 watts F3/F10 35/29, but port velocity is 39 m/s>

What did I miss?

I think you've gone past the driver's max excursion.

[MrkCrwly]

Re: Core 2-Way - Build Tread

Paul / Mark,

When I model the box in Jeff's Woofer Box, I get extremely high port velocity.
I have a 30 liter next box 2x3.5 vent whixh tunes the box to 38Hz. Using Zaph's TS params. Response pretty flat. 102dB @30 watts F3/F10 35/29, but port velocity is 39 m/s>

What did I miss?

I'm not big on the technical end of things, but maybe it is because you called it the "30 liter next box" and not the "30 liter TRS80-Amiga-ZX Spectrum-Core box". NeXT may be the next one.:rolleyes:
BTW Currently I am setup with a 2" dia x 2 1/2" long port. I have been listening in the 70-80 db range and heard nothing but sweet music.

[fastbike1]

Re: Core 2-Way - Build Tread

Ha-Ha. 30 liter NET (no fat finger this time) TRS-80 - Amiga - ZX Spectrum - Core and whatever else box.

It exceeds max excursion below 35HZ (the F3 point), but the peak is broad enough that is it over 20m/s from 25 to 45 Hz.

I don't doubt that it sounds sweet at 75 dB. The box model calculates that volume at less than a watt and port velocity at 8m/s. I don't doubt the design, but I wouldn't have expected velocity that high.

I think Paul uses Unibox and I would be curious to see a port velocity plot form the Amiga or TRS-80. Paul typically doesn't post those results.

Frankly the 2 1/2 in port puts a 2 or 3 dB peak at the tuning frequency.

I'm not big on the technical end of things, but maybe it is because you called it the "30 liter next box" and not the "30 liter TRS80-Amiga-ZX Spectrum-Core box". NeXT may be the next one.:rolleyes:
BTW Currently I am setup with a 2" dia x 2 1/2" long port. I have been listening in the 70-80 db range and heard nothing but sweet music.

[MrkCrwly]

Re: Core 2-Way - Build Tread

Speakers are done except for the walnut accent strips and tweaking the stuffing and port length.

Accent strips after some poly.

Attaching the accents strips.

Pieces of the foam that protected the RS180 surround during shipping made perfect glue clamps.

[Soundslike]

Re: Core 2-Way - Build Tread

Mark,
You are amazing! Your architectural training and experience reaallly shows. Very nice design. I'll have to admit -- I'm envious...

Ron

[MrkCrwly]

Re: Core 2-Way - Build Tread

Mark,
You are amazing! Your architectural training and experience reaallly shows. Very nice design. I'll have to admit -- I'm envious...

Ron

Thank you. That is very kind.

[MrkCrwly]

Re: Core 2-Way - Build Tread

Speakers complete.

OK. Complete except for some screws.

Goal of the design was to complement the fireplace. (No, that is not where the speaker will be placed.)

[MrkCrwly]

Re: Core 2-Way - Build Tread

Detail pics of the finished cabinet. I sure like the look of the RS drivers.

[james_e5]

Re: Core 2-Way - Build Tread

Those look awesome! Perfect match for the fireplace!

-j