More waveguide shootouts
Sometimes ago we did the follow-up of Waveguide shootout in Melbourne:
Red Spade Audio: Waveguide shootout
and part II:
Red Spade Audio: Waveguide GTG #2
We even had a waveguide-loaded plasma tweeter from Acapella!
The best measured results were:
D220Ti + Pyle/JBL clone wg
Also known as "Econowave"
D220Ti + Dayton 10" wg
B&C DE250 + Pyle/JBL clone wg
This was the most impressive and subjectively sounded best. I have now ordered the compression driver and will post a long-term listening test.
Plastic bolt-to-screw adapter is required to mount the DE250
On other note, I experimented with foam plugs. And while it smoothens the mid-high there is noticable loss of high frequency resolution. No foam is better sounding overall for my preference.
Sometimes ago we did the follow-up of Waveguide shootout in Melbourne:
Red Spade Audio: Waveguide shootout
and part II:
Red Spade Audio: Waveguide GTG #2
We even had a waveguide-loaded plasma tweeter from Acapella!
The best measured results were:
D220Ti + Pyle/JBL clone wg
Also known as "Econowave"
D220Ti + Dayton 10" wg
B&C DE250 + Pyle/JBL clone wg
This was the most impressive and subjectively sounded best. I have now ordered the compression driver and will post a long-term listening test.
Plastic bolt-to-screw adapter is required to mount the DE250
On other note, I experimented with foam plugs. And while it smoothens the mid-high there is noticable loss of high frequency resolution. No foam is better sounding overall for my preference.
And when you used the foam, did you re-EQ the device to be the same frequency response as without the foam? Because, if not, then of course you will loose HFs. The waveguide must be EQ'd for the foam in place, otherwise its not a realistic comparison.
Exactly. it's akin to buying a loudspeaker, and then swapping out with a less sensitive tweeter. At that point it's a whole new ball game and an optimized crossover is a given.
Resolution is about the time and frequency domain response, and yes the foam is altering both. the time domain effect of the foam is a good thing and the frequency domain is a side effect which can be corrected.
You wouldn't compare a speaker and its open baffle counterpart without the appropriate crossover mods right?
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Here's some homemade guides I made (actually made three sets of two, varying the roundovers). There's a thread over on AVS (Tell me how nice my new home-made waveguides look - Page 3 - AVS Forum) talking about them (and some arguing about other waveguides as usual of course).
Here are the horizontal measurements for the latest (using 4.2" radius roundovers):
Don't have plots of verticals on these, but should look something like this (of previous try):
I hope to get some foam from Earl to use in these, though may have to cut it myself (Earl, would you be up for selling me just a block of the foam?)
(last picture was from try#2, after painting)
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Here are the horizontal measurements for the latest (using 4.2" radius roundovers):
Don't have plots of verticals on these, but should look something like this (of previous try):
I hope to get some foam from Earl to use in these, though may have to cut it myself (Earl, would you be up for selling me just a block of the foam?)
(last picture was from try#2, after painting)
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Yes, of course the frequency response were made to match.
Paul (that gtg host) observed and measured the same thing with his system. Except that he got used to the effect and liked it, while I did not.
Sure, you'd have to tell me the size that you want. If my guess is right on the sizes, two blocks big enough to do those horns could get expensive - between $50 and $100 for the pair.
Is it not possible to make an oval oblate spehroid waveguide? I think Genelec and a few others use 'em.
Check this out !
DIY Sound Group
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Yeah - about $50 ft^3 is what you can expect just about anywhere unless you buy a whole bun. Then its maybe 1/2 of this. And don't forget all the waste > 50%.
Thats "not expensive"? That's almost as much as a compression driver costs. And its just foam! That makes the material cost of one of my Abbey plugs about $50 not including labor. Add labor and you are looking at almost $100 each. Not expensive?
Well in aquarium shop they sell such filter for $20 for a minute size. Wouldnt even be enough for a square wg.
Edit: and that's for one
Edit: and that's for one
Not all open cell foam that is 20-30ppi is the same. The stuff used in filters is not what you want. My guess is that it will have very little effect.
The reticulated foam I got from the aquarium store works well, and even the small plug of it has a big effect.
This is curious.
Were you able to measure the FR before and after using the foam? If so, did you see a couple of dB attenuation at the two highest octaves?
Yes, though my measures are rough. Yes, a small attenuation in the top octave or two.
Dayton 8" Waveguide
Recently I measured Dayton Audio 8" Waveguide with D220Ti and DE250
Dayton Audio H08RW 8" Round Waveguide 1" Threaded 270-308
Dayton 8" + D220Ti
Dayton 8" + B&C DE250 (with adapter)
They look remarkably similar.
Recently I measured Dayton Audio 8" Waveguide with D220Ti and DE250
Dayton Audio H08RW 8" Round Waveguide 1" Threaded 270-308
Dayton 8" + D220Ti
Dayton 8" + B&C DE250 (with adapter)
They look remarkably similar.
Yorkville Unity horn
We measured the Yorkville Unity horn at recent GTG.
Proud owner
Directivity, normalised:
Frequency plots, 0-90deg, 10deg increment, non-normalised:
The speakers sounded awesome. It's a celebrity ! So heavy it took 3 people to lift them to the measurement rig.
We measured the Yorkville Unity horn at recent GTG.
Proud owner
An externally hosted image should be here but it was not working when we last tested it.
Directivity, normalised:
Frequency plots, 0-90deg, 10deg increment, non-normalised:
The speakers sounded awesome. It's a celebrity ! So heavy it took 3 people to lift them to the measurement rig.