Dynaco - Long Speaker phasing question
I sold a pair of Dynaco A10s to a guy that had early Realistic 40-1276 Super Dome tweeters instead of the Seas. Don't laugh the early Realistic super domes sounded pretty sweet. They go down to 2khz versus the Seas 1.5khz but they roll off fairly smoothly. I own A25s with stock tweeters too and A/B'd them over a period of time. Seas win but only slightly IMHO. Realistic had better dispersion but not quite as magical as the Seas on that mid range Dynaco thing.
Anyhoot he hates the A10's and wants a full refund including shipping. It was a no return as-is auction but I want to maintain my audiokarma! He owns a few pairs of he A10's and A25s so I assume he's not just whining.
He uses them on a vintage Sherwood SS - S7100 I think, with a pair of bigger Bozak's on A and the Dynaco A10's on B. He thinks it is a gasket/seal problem at the Realistic speakers. I think the speakers are out of phase and mitigating each other!! I just told him to try switching polarity. Here is my message to him - does it make sense??
"I hope that is the issue but I doubt it.
Here's why: Aperiodic baffle designed speakers allow lower and middle frequencies/air to escape from the baffle in a engineered/controlled manner. In Dyanco's case a ingeniously designed set up. It is carefully restricted air movement - in this case a fiberglass bat material. Air is like water and takes the path of least resistance so a minor leak at the tweeter would not really majorly affect those lower frequency ranges - too much air needs to move. Yes it may cause a million other issues from whistling to hum etc that may or may happen or be audible. Okay so it needs 10 cents worth of plumbers putty to fix that.
I think the A10's are out of phase with the Bozaks. The Bozaks are "swallowing" the Dynacos'. When out of phase the A10 small drivers are moving 100% opposite the movement of the BZ's and crossing out the A10's almost 100%. Especially with the little 6.5 versus the 10's?? in the Bz's. On a lower freq they should both be moving out pushing air but one is moving the opposite way and it actually mitigates the sound! That is why passive radiator designs must put the radiator on the back because they are out of phase with front woofer. The box becomes an "infinite baffle" in theory so the phase issue is not really there.
Humor me and try the A10s alone. I assume sound okay. Then try the with the BZ's with the A10's - BUT reversing the polarity of the A10's and leave BZ's as you have them. What was the result.
The reason I am hanging on this is they sounded pretty killer to me but I NEVER tried them with another set of speakers together since my Sherwood S7000 only has one set of speaker outputs - no A and B set. If my theory is right their is nothing wrong except phasing.
I am going to put this on the audiokarma site and see what help or flames I get!! I will let you know.
"So - am I wrong here, Donnie?" (Big Lewbowski humor!!)
I sold a pair of Dynaco A10s to a guy that had early Realistic 40-1276 Super Dome tweeters instead of the Seas. Don't laugh the early Realistic super domes sounded pretty sweet. They go down to 2khz versus the Seas 1.5khz but they roll off fairly smoothly. I own A25s with stock tweeters too and A/B'd them over a period of time. Seas win but only slightly IMHO. Realistic had better dispersion but not quite as magical as the Seas on that mid range Dynaco thing.
Anyhoot he hates the A10's and wants a full refund including shipping. It was a no return as-is auction but I want to maintain my audiokarma! He owns a few pairs of he A10's and A25s so I assume he's not just whining.
He uses them on a vintage Sherwood SS - S7100 I think, with a pair of bigger Bozak's on A and the Dynaco A10's on B. He thinks it is a gasket/seal problem at the Realistic speakers. I think the speakers are out of phase and mitigating each other!! I just told him to try switching polarity. Here is my message to him - does it make sense??
"I hope that is the issue but I doubt it.
Here's why: Aperiodic baffle designed speakers allow lower and middle frequencies/air to escape from the baffle in a engineered/controlled manner. In Dyanco's case a ingeniously designed set up. It is carefully restricted air movement - in this case a fiberglass bat material. Air is like water and takes the path of least resistance so a minor leak at the tweeter would not really majorly affect those lower frequency ranges - too much air needs to move. Yes it may cause a million other issues from whistling to hum etc that may or may happen or be audible. Okay so it needs 10 cents worth of plumbers putty to fix that.
I think the A10's are out of phase with the Bozaks. The Bozaks are "swallowing" the Dynacos'. When out of phase the A10 small drivers are moving 100% opposite the movement of the BZ's and crossing out the A10's almost 100%. Especially with the little 6.5 versus the 10's?? in the Bz's. On a lower freq they should both be moving out pushing air but one is moving the opposite way and it actually mitigates the sound! That is why passive radiator designs must put the radiator on the back because they are out of phase with front woofer. The box becomes an "infinite baffle" in theory so the phase issue is not really there.
Humor me and try the A10s alone. I assume sound okay. Then try the with the BZ's with the A10's - BUT reversing the polarity of the A10's and leave BZ's as you have them. What was the result.
The reason I am hanging on this is they sounded pretty killer to me but I NEVER tried them with another set of speakers together since my Sherwood S7000 only has one set of speaker outputs - no A and B set. If my theory is right their is nothing wrong except phasing.
I am going to put this on the audiokarma site and see what help or flames I get!! I will let you know.
"So - am I wrong here, Donnie?" (Big Lewbowski humor!!)
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