Vent is at the bottom. Yes i know the shape is not perfect.But it is as it is for other reasons.
Never studied phase plugs. So what benefits this driver gets from phase plug?
Never studied phase plugs. So what benefits this driver gets from phase plug?
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Smoother response. Gets rid of what is happening under the dustcap (oil can resonance), and the crap happening inside the dustcap (pushes anything way up in frequency).
Nothing wrong with the box shape, it looks like a really big microTower, (original thread and one of the most recent)
microTower bipolar ML-TL for CHR-70 or EL70
https://www.diyaudio.com/community/threads/microtower-revisited.364581/
You just need to know that the vent (restricted terminus) will need to be longer than your BR modeler shows. Also being endloaded it should likely be largely filled with damping material.
What is the total box net volume?
dave
Nothing wrong with the box shape, it looks like a really big microTower, (original thread and one of the most recent)
microTower bipolar ML-TL for CHR-70 or EL70
https://www.diyaudio.com/community/threads/microtower-revisited.364581/
You just need to know that the vent (restricted terminus) will need to be longer than your BR modeler shows. Also being endloaded it should likely be largely filled with damping material.
What is the total box net volume?
dave
Get it. But still phase plugs are not very common in drivers..
Volume 60l and yes quite a bit of damping material inside
Actually they are quite common. And i have not yet met a whizzer coned driver that does not benefit from their addiiton.
60 litres is good for a single driver in a sealed box. In a vented box with 3 drivers i would expect more like 200 litres would be appropriate. It would be interesting to see what heaviy stuffing the vent would do.
With BR loudspeakers damping is usually kept to a minimum, so with lots it has further distanced itself from a reflex.
dave
Still breaking in, this is my third pair so I know what to expect.
And newly completed folded open baffle bass bins to match my dipole satellites. So far exactly the bass I was after. Full, harmonically rich, satisfying for music and cinema, but not disturbingly ground penetrating and disturbing to my neighbours.
Using a BBE active crossover to highpass the satellites at 170 hertz, and lowpass a sub plate amplifier at 70 hertz.
A much more natural balance top to bottom, and after a couple hours fine tuning, settled in for about a 6db 40 hertz narrow Q boost.
I intended to hook up for stereo bass, but now can't be bothered pulling a stereo amp out of storage for bass.
Using a BBE active crossover to highpass the satellites at 170 hertz, and lowpass a sub plate amplifier at 70 hertz.
A much more natural balance top to bottom, and after a couple hours fine tuning, settled in for about a 6db 40 hertz narrow Q boost.
I intended to hook up for stereo bass, but now can't be bothered pulling a stereo amp out of storage for bass.
Very pretty. With 3 8" full ranges did you have to employ some tricks to control dispersion?
I use it to create some sort of 3D effect. So yes some tricks in DSP. You can find some info on my page https://www.baffless.com/single-speaker-stereo-1
A beautiful build.
People here are certainly more reasonable than Facebook groups. I posted one there recently, because I was surprised a full range rear mounted like this gained a little bump that made movie dialogue a lot easier to follow than tradition front flush mounting it, which I also had used.
The administrator told me to fix it by front mounting it. I said no, I had posted it because it suited me better as was.
Then he told me I had no clue what I was talking about, and then told me I should buy a mini DSP and fix it.
I said there's nothing to fix. I posted because it is the only driver I've used that sounds more intelligible at all volumes by rear mounting it, and then using a large roundover.
He said I obviously don't know what I'm talking about, seem mentally deficient, and was missing an opportunity to listen to him.
When I asked to see the frequency response he was basing his opinion on, and also wondered when he had been in my living room to hear the obvious differences, Jarhead, or whatever this administrator's name is, told me I was lying, and he would be removing the post so people couldn't see me disagreeing with him.
Did he mean he had sneaked into my home and compared the different versions of my speakers?😄
Ranting done.
I have tried something similar with just two Mark Audio 12PW facing different ways, wired in phase for stereo.
I have extra drivers, and am considering using a third in a Hafler style differential, front facing.
Is this what you've done?
Could you post pictures? I wouldn't mind having a (switchable) rear-facing Mark Audio full range augmenting the front-facing full range if it helped with dialogue intelligibility. Many decades ago, I heard some Snell Type C speakers with a rear-firing tweeter that sounded nice. I remember that soundstage till today.
I did visit your page, and it gave me ideas. What you have done is sort of a variation of what Polk did with their SDA speakers - taking a bit of the left signal and feeding it back to the right channel and vice versa.
Does your design require one channel in both the amp and speaker to be inverted?
What if you had two speakers and reversed the connections? Aka, one speaker with right-channel inverted and the other with left channel inverted?
Everything was hooked in positive polarity. No pictures; I inadvertently cleared my cache.
Now I'll have to do another and try your ideas, lol
Polk SDA speakers koks like they are doing crosstalk cancelation which is completely different aproach.
FYI I was reading about PS Audio's new FR30, and they too use a rear tweeter.
I think the SDA was an attempt to cancel the left channel bleed into the right channel and vice versa.
Some decades ago Dynaco promoted a three speaker connection to give listeners the option of a "centre" speaker.
Neat!
I've often used a David Hafler differential positive-positive connected speaker as a single surround.
I'll have to give this a whirl as a centre.
