Need help building open baffle/bass reflex hybrid

Hi all,

I am attempting to do my first build and am not very tech savvy so bear with me. My general idea is to mimic the Nola Brio speaker. It is a hybrid speaker consisting of two identical full range 3.5 " drivers. The configuration is a ported box housing on the bottom driver and an open baffle housing the top driver. I need advice and direction on all aspects. Here are my initial questions:

1. Should I wire the drivers in parallel or series configuration?
2. I don't want to blow the driver's up with my 250w/channel amp and so need direction on power handling (i assume this plays into how I choose to wire the speakers abnd how I choose the drivers)
3. Advice on drivers- I would like to use very low weight paper drivers to get a very quick and detailed sounding speaker (any recommendations would be great.. TangBand makes some very pretty looking ones)
4. Given that they will be identical full range drivers do I need a crossover? would there be advantages of filtering out bass frequencies in the upper driver ?(this is what the maker of the Nolas does.. He says he uses one simple capacitor in each speaker)?

Thanks in advance for any direction you could give me.
 
Wow, Is that a pair of TC9FD in there? Does look like them.

Selling the Brio t $3,500... that's a bit of money spent shining those enclosures....

Certainly looks like the TC9FD. Now it looks like I'll have to try something like this.
I'd think rolling the top driver off around 200 Hz and letting the bottom go full range might be worth a try. It could be called a 1.5 way.
My question would be about the BR box. The TC9 has a fairly high QTS for a vented enclosure, from my understanding.

Peerless by Tymphany TC9FD18-08 3-1/2" Full Range Paper Cone Woofer

http://www.parts-express.com/pedocs/specs/264-1062--tymphany-tc9fd18-08-spec-sheet.pdf

Mike
 
Hahahaha 3.5k for less than $100 worth of components for the stereo speakers.

The top TC9FD is run open baffle with the option of sound absorptive material behind them. This would allow the "resonance free" sound of open baffle without the rear wave radiation to the walls. 4" of Roxul Rockboard 40 will absorb everything above 125hz.

My guess is the crossover occurs where the top TC9FD rolls off due to open-baffle.

Should be incredibly simple to clone.. with the exact same drivers too. Hell you can even use the Scanspeak Discovery 10F/8414G-10 which are better versions of the TC9FD, and arguably the best small fullrange driver.

"Worlds Best Value" LMAO This is pretty epic. :rofl::eek::rofl:

In the video the reviewer speakers that each drivers moving mass is 2.4 grams. Yep, these are the TC9FD. ROFLMFAOADLLLLL :rofl::rofl::rofl::rofl:
 
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Here's a price list for the DIY minded to get something similar looking and get as good if not better sound...

4x TC9FD at $12 each...
1x sub driver, about $50
a computer (most of us have one, and maybe an older one laying around nobody uses...)
JRiver, $50 for EQ, routing the 6 channels needed, convolution, room corrections, etc...
An audio interface, nice one like the Steinberg UR28M, $400.

Although, with some design skills, maybe could bring the number of channels down to 4, and use stereo subs instead!

Some time and a little cash to build 3 enclosures...

So, about $550 + $50 of wood and little things like binding posts, etc... gets you a system you can tailor to your liking, route audio, apply endless Xover, EQ, etc....
 
The designer says that there is only a single capacitor used for each stereo speaker, which is used on the upper dipolar driver. No need for active components if we wish to just clone these.

So..
4x TC9FD at $12 each... $48
2x Capacitor.. (1st order crossover) cheap to expensive
Foam Board.. $13
Hot Glue Gun & Glue.. $10
Screws.. $3 max
2x (1.5" x 4" Port) (61hz @ .25 ft^3).. $3.30
Hobby knife.. $6

Total = ~$100+ for the two stereo speakers

I'll let you guys figure out the subwoofer.
 
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Hey guys I modeled xmax of the driver in the ported .25 ft ^3 @ 59hz enclosure, and on the dipole driver.

Xmax is achieved @ 2.6W per driver in the ported enclosures, while xmax is achieved @ 4W per driver in the open baffle configuration. There is NO NEED for a crossover to protect the open baffle driver. Both can run full range.

This means we should be getting a cardioid response throughout the frequency range. :D

Simply connect the drivers in parallel for a 4 Ohm nominal load.

The sensitivity of the TC9FD is 83.5 dB 1W/1m. Which means 89.5dB 1W/1m for 4 drivers if im not mistaken. If we take the safe route of 2.6W per speaker driver.. so 10 Watts total, this means a maximum output of around 99dB at 1 meter.
 
They (Nola) do mention 90dB for the satellites...

Just for fun, I'm going to make an open baffle add-on to put on top of my TABAQs... it should be quite interesting.

Yup, this is on my "soon" list of speakers to prototype. The only improvement I can add to this design, other than the possible omission of a hi-pass crossover, is that you want your 2 speaker drivers per channel as close as possible due to comb filtering. There is a big debate on whether comb filtering is audible or not though, so don't let hold you back from experimenting. :p
 
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Founder of XSA-Labs
Joined 2012
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Nola Brio satellite:
An externally hosted image should be here but it was not working when we last tested it.


Best Sound award at 2016 CES by AV Showrooms? I am not surprised that the lowly paper cones TC9FD in a 2.1 satellite system can sound good, but to be the best sound at CES is kind of surprising. Maybe I was onto something with my dual driver Nautaloss? Not open baffle on top but sounds amazingly good for a $26 speaker.

http://www.diyaudio.com/forums/full-range/247598-nautaloss-ref-monitor.html

391320d1388726734-nautaloss-ref-monitor-nautaloss-ii-build-06.jpg


When used with a sub crossed below 120Hz system was quite impressive. Keep in mind that the Brio includes a powered sub, piano black gloss finish, and that expensive coupling cap :)

Anyhow, to be profitable there is a 5x to 10x markup in price from cost to make so that puts system at $350 to $700 in parts and assembly. Sounds about right as 250w class AB amp driven 10in sub is probably at least $150 to $300. The cabinets are not cheap.

It's a fair price for a commercial system and you can do for less if you make your own.

1.5 way on satellites probably was used to get around the baffle step loss below 1khz - port is tuned really high around 90Hz is my guess. This combines with high Pass on open baffle to allow a lot of power handling because the sub plate amp serves as the main amp and crossover.
 
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They have a 8" sub... ;)

Yeah, X, I believe they have been reading your threads on "Best bang..." and the "3 inch comparative...", amongst others like your Nautaloss...

I blame the prices on the AV business model. Just getting a nice room at one of those audio shows is something like $5,000. Then, the cost of going there, carrying/shipping the equipment, having personnel around for the duration of the show, rooms to sleep there for a couple of nights....

But, without the shows, it would take more time to get recognition... kind of a catch-22.

If you have to add the cost of a distributor, it doubles right there.
 
Bensturgeon - Don't know if you're aware but I would think that even though this is a small speaker, it would still need to be placed at least 3ft away from any wall to sound its best just like most other open baffles. The lxmini is supposedly an exception but I've never heard one.
 
Bensturgeon - Don't know if you're aware but I would think that even though this is a small speaker, it would still need to be placed at least 3ft away from any wall to sound its best just like most other open baffles. The lxmini is supposedly an exception but I've never heard one.

Well I might be wrong, but doesn't a monopole and dipole add to a cardioid response? If I'm right.. this speaker should be cardioid over a large bandwidth just like the lx mini.