DIY Boston Acoustics Full Range Speaker

[maxsumit]

My first attempt at DIY Speakers.

Parts List with cost:- Total cost - Rs 15390/
Driver - Boston Acoustics Full Range Speaker Rs 1300/pair.
Plywood 18 mm X 48 sq ft Rs 3120 - Speaker
Plywood 15mm X 32 sq ft Rs 1920 - Stand
Jigsaw Machine Rs 1500
Laminate Sheets 3 - Rs 1800
Fevicol Marine 3 kg - Rs 750
Carpenter charge - Rs 4000
Others - Rs 1000

Step wise Pics :-

 

[sadik]

Nice Job .. Post some Drawings of your Enclosure.

 

[maxsumit]

Total weight of each speaker -18 kg no knuckle sound.
Total weight of each stand - 12 kg.

It is a translaminate design incorporating internal horn shape.

 

[VSTEREO]

Excellent work.
I am about to take this driver project for this month (planning for Ported). Your design is unique, would be interested to hear more about it. How does it sound ? May I know your source ?

 

[maxsumit]

Thanks, the sound is melodious as intended for listening music.
As usual, the highs are little shouty, which I tamed by putting some wool around the whizzer cone.
Bass is well defined.

Amplifier - ALLO Volt + stand alone amplifier
DAC - ALLO BOSS DAC based on Raspberry PI 3
Flac files.

 

[VSTEREO]

It is a translaminate design incorporating internal horn shape.

We have same driver in Ported and Sealed design done by our forum members. May I know the reason for going with translaminate design ? Is translaminate design more suitable for this driver to get its full potential?

 

[keith_correa]

It is a translaminate design incorporating internal horn shape.

What is a "translaminate" design?

 

[maxsumit]

Translaminate design

The speakers are ported and they are 16 inches deep.

 

[raj12345]

Great Effort but I think its costly as Drivers Cost is Only 7% of Total Money Invested.

 

[maxsumit]

It was conceptualized as such that I can swap with better hifi drivers in the future. Drivers such as Dayton Audio, Tangband, Fostex, Audio Nirvana or any vintage ones, which is hard and costly affair to procure.

 

[maxsumit]

We have same driver in Ported and Sealed design done by our forum members. May I know the reason for going with translaminate design ? Is translaminate design more suitable for this driver to get its full potential?

I wanted to make solid speaker box, which is vibration free...wherein I thought of building translaminate design.

 

[shaan]

Very nice! Translaminate design does indeed promise near zero enclosure resonance.

I recently built a pair sealed BS with these drivers and for the amount of money invested it is a success. There aren't conventional (proper) bracing inside the cabinet. Just two 2"x3" heavy wood pieces placed with favicol+sawdust so that right and left wall's resonance dies (judging by ears only, took some time to find the optimum place for them). For padding I used vertical fiber coir doormats with rubber base affixed with rubber glue, covers whole back wall, top/bottom and front below driver. Stuffing with polyfill seemed to be tricky as too much or too less seemed to ruin low-mid performance.

Driven by an active crossover bi-amp system crossed at 150Hz, these have a smooth and balanced low-mid and vocal impression. Highs a so high that no tweeters are needed, however, VERY directional. To me this seemed to be the only problem with the driver's response. Also, due to beaming these seem to be screaming at 0-10 degrees listening position and I'm inclined to see what happens if the angular dispersion of HF components are increased. For this I am making a pair wooden phase plugs. Will update once tests with them are done.

 

[maxsumit]

Very nice! Translaminate design does indeed promise near zero enclosure resonance.

I recently built a pair sealed BS with these drivers and for the amount of money invested it is a success. There aren't conventional (proper) bracing inside the cabinet. Just two 2"x3" heavy wood pieces placed with favicol+sawdust so that right and left wall's resonance dies (judging by ears only, took some time to find the optimum place for them). For padding I used vertical fiber coir doormats with rubber base affixed with rubber glue, covers whole back wall, top/bottom and front below driver. Stuffing with polyfill seemed to be tricky as too much or too less seemed to ruin low-mid performance.

Driven by an active crossover bi-amp system crossed at 150Hz, these have a smooth and balanced low-mid and vocal impression. Highs a so high that no tweeters are needed, however, VERY directional. To me this seemed to be the only problem with the driver's response. Also, due to beaming these seem to be screaming at 0-10 degrees listening position and I'm inclined to see what happens if the angular dispersion of HF components are increased. For this I am making a pair wooden phase plugs. Will update once tests with them are done.

Good Job, please keep me updated with your wooden phase plug mod.

 

[shaan]

One prepared. One more to go.

Now, how to safely remove the dust cap without damaging the twizzer cone?? It seems attached with rubber glue.

 

[Hari Iyer]

Now, how to safely remove the dust cap without damaging the twizzer cone?? It seems attached with rubber glue.

Follow these steps and you should be through

FE167 Duscapectomy

Cheers,

 

[maxsumit]

One prepared. One more to go.

Now, how to safely remove the dust cap without damaging the twizzer cone?? It seems attached with rubber glue.

My idea is to use the ends of this rolling pin, cut in exact size to be used as Phase plugs. What do you think ?? Will it work ??

 

[Sumanta]

That's a great idea Maxsumit!

 

[shaan]

OH! Of course! Thanks for the idea max! :signthankspin:

 

[sudhirbhosale]

Very nice! Translaminate design does indeed promise near zero enclosure resonance.

Does transmission line help to achieve similar benefit not fully but upto some extent? Since it has channel inside box hence has good lateral bracing throughout height.

 

[shaan]

Hello Sudhir.

I'm not quite sure. I guess enclosure resonance would not be as low as a translaminate.