Keeping this thread alive....
I just got my 828 cabinets done and up and running with 805b horns / 299 8A combo.
Pretty happy with initial setup up. Have made one 8" port and made 4,6,8 inch tubes to try.
Did bracing and filled horn flair with sand.
Many thanks to GM, Pano, Cal, and many others here at diyaudio and Altec user board.🙂
I just got my 828 cabinets done and up and running with 805b horns / 299 8A combo.
Pretty happy with initial setup up. Have made one 8" port and made 4,6,8 inch tubes to try.
Did bracing and filled horn flair with sand.
Many thanks to GM, Pano, Cal, and many others here at diyaudio and Altec user board.🙂
Experimental 421 8lf in them for now.
They came with the cabs because they were rentals
I cut the metal dust cap off and put 515 type dust cover and covered the magnet hole.
After I get used to them and have time I will try a pair of 4168a I have.
They came with the cabs because they were rentals
I cut the metal dust cap off and put 515 type dust cover and covered the magnet hole.
After I get used to them and have time I will try a pair of 4168a I have.
Excellent. I wish you lived closer.
The 421 in that cabinet is not an experiment. Alec used that combo in the 1236 system. That box is pretty forgiving.
Good work.
The 421 in that cabinet is not an experiment. Alec used that combo in the 1236 system. That box is pretty forgiving.
Good work.
What's a couple thousand miles for a good cold beer and some audio fun )
Thanks Cal
Things are getting good here. But I need help to understand box tuning software vs room gain.
I have found the bass is most tuneful and defined with lower tuning (longer tubes ) yet in sims that shows about 28 hz tuning and the plot falling off pretty fast after 60hz.
Tuned higher it's all thumpy one note bass.
I have found the bass is most tuneful and defined with lower tuning (longer tubes ) yet in sims that shows about 28 hz tuning and the plot falling off pretty fast after 60hz.
Tuned higher it's all thumpy one note bass.
Well, there are "sims" and then there is real life/reality.
Often times, the two are not in the same neighborhood !
Alter landing A7 wings
Hello,
I have been using these A7 for more than 2 decades and after hearing some bigger Altec in Vietnam I start thinking about adding so called wings.
I did Google a bit but info is hard tofind.
I can attach a panel on both sides but on the outside there is not much room for a big panel. Need the panel on left and right side of the box to be identical dimensions? Can I "" fold "" them towards listening position?
Do these panels need to have a flat surface? Wold it be possible to use these diy wooden diffusers instead of flat panels?
The wooden horns I am using on top of the bass bins are directed towards listening position so integrating thishorn into a big panel would be a bit hard.
Greetings, eduard
Hello,
I have been using these A7 for more than 2 decades and after hearing some bigger Altec in Vietnam I start thinking about adding so called wings.
I did Google a bit but info is hard tofind.
I can attach a panel on both sides but on the outside there is not much room for a big panel. Need the panel on left and right side of the box to be identical dimensions? Can I "" fold "" them towards listening position?
Do these panels need to have a flat surface? Wold it be possible to use these diy wooden diffusers instead of flat panels?
The wooden horns I am using on top of the bass bins are directed towards listening position so integrating thishorn into a big panel would be a bit hard.
Greetings, eduard
Attachments
I've used side wings on A5 systems. They worked when the box was well away from the walls, in a large room. In a smaller room I didn't really get much benefit. Corner placement did give low end extension, without much change in the bass horn.
Basically the extensions make the bass horn bigger, meaning it's efficient at lower frequencies. The also alter baffle size, meaning baffle step correction would happen at a lower frequency.
Basically the extensions make the bass horn bigger, meaning it's efficient at lower frequencies. The also alter baffle size, meaning baffle step correction would happen at a lower frequency.
Hello Pano,
I remember reading about the wings in a French magazine some decades ago.the -3db point will move down a bit . If I remember well about 10hertz/cps but if still could be a big change for your Ears?
My altecs are already not to far from the side walls. Maybe I can figure out some construction that willnot damage the Cork surface of my boxes..
I did some of these acoustic diy absorbers by friends in Vietnam they look reallyrics nice.would be nice if they could be used as wings as well but I have my doubts.
Greetings, eduard
Pso somehow I think these wings look nice
I remember reading about the wings in a French magazine some decades ago.the -3db point will move down a bit . If I remember well about 10hertz/cps but if still could be a big change for your Ears?
My altecs are already not to far from the side walls. Maybe I can figure out some construction that willnot damage the Cork surface of my boxes..
I did some of these acoustic diy absorbers by friends in Vietnam they look reallyrics nice.would be nice if they could be used as wings as well but I have my doubts.
Greetings, eduard
Pso somehow I think these wings look nice
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That looks great Eduard. 
All I remember about the system in Paris is that we liked it better with the wings than without. What do you think?
To get benefit from the corners, mine had to be shoved right into the corner. Close was not good enough.
All I remember about the system in Paris is that we liked it better with the wings than without. What do you think?To get benefit from the corners, mine had to be shoved right into the corner. Close was not good enough.
30" W cab/~102 Hz to 50" W/~61 Hz or a bit lower to right around the original 800's box tuning if the original top baffle is used, so likely audible even without it and considering room effects.
Building into a false wall corner though is where the real gains are, especially in a below grade concrete block basement as me and the then neighbor that bought my DIY A7-500s found out. Combined with the 411s I put in the bottom half of the cabs there was more bass available than any recording we had, still going strong even below the signal generator's 20 Hz lower limit.
Depends on their effective bandwidth [BW]. If designed for > ~150 Hz, then theoretically as long as they're sufficiently rigid/braced, any added damping material shouldn't effect them.
By the same reasoning, they probably wouldn't be of much use as absorbers either since they wouldn't be optimally placed.
GM
Hello,
Only the Cork covered altec is mine . All the others are from the Internet.
I did attach a copy of the French article. As you can see the measured response changes just a little bit but for your ears it might be a bigger improvement.
I think better tolocate absorbers elsewhere because the panels need to reffect to get an improvement in think.
Still outside my country but once I am back in will try adding wings.
Greetings, eduard
Only the Cork covered altec is mine . All the others are from the Internet.
I did attach a copy of the French article. As you can see the measured response changes just a little bit but for your ears it might be a bigger improvement.
I think better tolocate absorbers elsewhere because the panels need to reffect to get an improvement in think.
Still outside my country but once I am back in will try adding wings.
Greetings, eduard
Attachments
Thanks for the graph, I remember seeing that a long time ago.
The wings do help, but corner placement helps the most. Mine played well into the mid 30s in the corner, no wings.
The wings do help, but corner placement helps the most. Mine played well into the mid 30s in the corner, no wings.
