Larger Semi-Omni Development

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CycleCoach
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Re: Larger Semi-Omni Development

Unread post by CycleCoach » Thu Aug 03, 2017 3:17 pm

Brilliant!
Current System: Macbook Pro, Starting Point Systems DAC 3, NVA A20, NVA P50SA, NVA LS2, Rogers LS4a

Chunk McDaniel
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Re: Larger Semi-Omni Development

Unread post by Chunk McDaniel » Thu Aug 03, 2017 3:46 pm

So is the bass cabinet ported now? Or was there a port on the base originaly?

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SteveTheShadow
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Re: Larger Semi-Omni Development

Unread post by SteveTheShadow » Thu Aug 03, 2017 4:08 pm

I will be using a down-firing, expanding, folded transmission line for the bass reinforcement; much better than your average ported cabinet, and the excellent mid-range performance of the 10 inch Faital Pro drive unit, once I had listened to it running wide open in free air, made me realise that it would have been frankly criminal to use it as a bass only driver.

That unit is a sleeper methinks. Incredible VFM if it does the biz as I am fairly confident it will.

Used in this way as the up-firing bass/mid unit, the rear of the cone energising the transmission line from a point 50% along its length, it will give bass down to 30Hz at -3dB with the terminus wall and floor loaded.

Any further sealed box experiments will use the Doc modded 12 inch drivers, I got off him a while back.
That'll be done once I've got these up and running.
BTE Designs modified Lenco L75 idler turntable, Rega R200 Tonearm, Goldring E3 MM cartridge, NVA Phono1 phono stage.
Mac-Mini music server with iTunes, AppleTV4 media streamer, Musical Fidelity M1 DAC,
NVA A20/P20, 25WPC stereo power amplifier/passive control unit,
own design, semi-omnidirectional, transmission line speakers- "The Flatback Banned".

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SteveTheShadow
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Re: Larger Semi-Omni Development

Unread post by SteveTheShadow » Sun Aug 13, 2017 10:33 pm

OK,
After a bit of a time lapse.
Here's the cross sectional drawing of the speaker:
Image
Not quite to scale, but it'll do for illustrative purposes.

The volume of the cabinet working in conjunction with the characteristics of the 10 inch driver, means that the port can be either open as a transmission line or can be closed to allow the cab to work as an acoustic suspension type.
This means that when it is built, it can do a bake-off with itself, to determine the preferred bass loading method.
Should be interesting.
BTE Designs modified Lenco L75 idler turntable, Rega R200 Tonearm, Goldring E3 MM cartridge, NVA Phono1 phono stage.
Mac-Mini music server with iTunes, AppleTV4 media streamer, Musical Fidelity M1 DAC,
NVA A20/P20, 25WPC stereo power amplifier/passive control unit,
own design, semi-omnidirectional, transmission line speakers- "The Flatback Banned".

Simon Hickie
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Re: Larger Semi-Omni Development

Unread post by Simon Hickie » Tue Aug 15, 2017 5:32 pm

Steve, is the driver the Faital Pro 10FE200 or one of the pricier offerings?
“The reasonable man adapts himself to the world: the unreasonable one persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man.” George Bernard Shaw.

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SteveTheShadow
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Re: Larger Semi-Omni Development

Unread post by SteveTheShadow » Tue Aug 15, 2017 5:37 pm

The driver is the 10FE200.
Don't tell anyone how good it is or they'll all want one. ;)
BTE Designs modified Lenco L75 idler turntable, Rega R200 Tonearm, Goldring E3 MM cartridge, NVA Phono1 phono stage.
Mac-Mini music server with iTunes, AppleTV4 media streamer, Musical Fidelity M1 DAC,
NVA A20/P20, 25WPC stereo power amplifier/passive control unit,
own design, semi-omnidirectional, transmission line speakers- "The Flatback Banned".

Simon Hickie
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Location: East Staffordshire
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Re: Larger Semi-Omni Development

Unread post by Simon Hickie » Tue Aug 15, 2017 5:46 pm

They look like good candidates for an OB project too.
“The reasonable man adapts himself to the world: the unreasonable one persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man.” George Bernard Shaw.

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SteveTheShadow
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Re: Larger Semi-Omni Development

Unread post by SteveTheShadow » Tue Aug 15, 2017 6:19 pm

Definitely.
BTE Designs modified Lenco L75 idler turntable, Rega R200 Tonearm, Goldring E3 MM cartridge, NVA Phono1 phono stage.
Mac-Mini music server with iTunes, AppleTV4 media streamer, Musical Fidelity M1 DAC,
NVA A20/P20, 25WPC stereo power amplifier/passive control unit,
own design, semi-omnidirectional, transmission line speakers- "The Flatback Banned".

Simon Hickie
Posts: 499
Joined: Mon Feb 27, 2017 1:47 pm
Location: East Staffordshire
Great Britain

Re: Larger Semi-Omni Development

Unread post by Simon Hickie » Tue Aug 15, 2017 8:42 pm

Hmm, Eminence Alpha 15, Faital Pro 10FE200 and a suitable tweeter perhaps.
“The reasonable man adapts himself to the world: the unreasonable one persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man.” George Bernard Shaw.

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SteveTheShadow
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Re: Larger Semi-Omni Development

Unread post by SteveTheShadow » Tue Aug 15, 2017 9:04 pm

That lot sounds like it has a great deal of potential for fab sound quality.
BTE Designs modified Lenco L75 idler turntable, Rega R200 Tonearm, Goldring E3 MM cartridge, NVA Phono1 phono stage.
Mac-Mini music server with iTunes, AppleTV4 media streamer, Musical Fidelity M1 DAC,
NVA A20/P20, 25WPC stereo power amplifier/passive control unit,
own design, semi-omnidirectional, transmission line speakers- "The Flatback Banned".

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