Jim Griffin A10.2 MLTL with variation

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Jazzkido, interesting experiment you got going there. Like Skeeter99 I though that the horns would mainly amplify mids and high and make the speakers overly bright. Wonder how this would apply to other designs...

Scott, good to see you posting again at the forum. Are the Alp 12s still in the Super Pensils or you building something else?


Dear zman01, Now that you have mentioned it I went back and have a harder listen with the horns on. I do not have any equipment setup to do measurements so I rely on my hearing entirely. You are correct that the mids and highs are amplified more than the bass. The result is kind of like listening to music through a tunnel. I think that may be one charateristic of horns. My Griffin built is not quite finely tuned yet as I am still treaking with the damping and spikes. Without the horns, they are lacking a bit in the bass but the horns did amplify the bass a bit more. Highs distortion is also a problem when I play in louder volume because the speakers are quite tall and thin and I can feel al lot of vibration on the cabinets. That may be one reason why it did not sounded overly bright with the horns on. The horns may have dampen some of the vibrations and less distortions. Another thing is that I have the speakers positioned in the corner of the room and the sound stage may not be quite balanced.
 
The best way to overcome those nasty cabinet vibrations (and they DO become part of the sound) is to brace the living $#!+ out of the cabinets. The result should be that when you rap your knuckles on the side it sounds like you're tapping on a brick. That should be the goal although it is seldom realized even in high-end systems.
 
Dear silverhairbp, I just came back from holiday. Actually, I have had thought of the same idea of bracing the speakers on the outside. My thoughts were may be to use some heavy fabric materials like wool or PVC and glue them on the outside of the cabinet. I have also had the idea of building double cabinets - an inner cabinet and an outer cabinet. Now, it looks like I may really need to go ahead with this plan. Will keep updating. Thanks, Michael
 
Dear silverhairbp, I just came back from holiday. Actually, I have had thought of the same idea of bracing the speakers on the outside. My thoughts were may be to use some heavy fabric materials like wool or PVC and glue them on the outside of the cabinet. I have also had the idea of building double cabinets - an inner cabinet and an outer cabinet. Now, it looks like I may really need to go ahead with this plan. Will keep updating. Thanks, Michael

Adding mass alone will not necessarily eliminate resonances from under-braced enclosure panels, but it can lower the resonant frequency and decrease the speed at which the energy is dissipated - perhaps counter-productively so .

I still think you'd be better served by attempting to install several timber bracing struts between the larger panels inside the boxes - both side to side and front to back. It would require some careful measuring and probably several cuts to get a just snug enough fit. Since you've already contemplated adding external layers, these struts could be screwed from the outside before covering or re-finishing.
 
Adding mass alone will not necessarily eliminate resonances from under-braced enclosure panels, but it can lower the resonant frequency and decrease the speed at which the energy is dissipated - perhaps counter-productively so .

I still think you'd be better served by attempting to install several timber bracing struts between the larger panels inside the boxes - both side to side and front to back. It would require some careful measuring and probably several cuts to get a just snug enough fit. Since you've already contemplated adding external layers, these struts could be screwed from the outside before covering or re-finishing.

HI Chrisb, Thanks for the advice. I think you have a point there because of the long panels on these speakers. Bracing from front to back would definitely help with stabilizing the removable panel in the back. What I am worried about is that the added timber may reduce the cabinets' internal volume. Would metal made internal bracing work? Thanks, Michael
 
Abelma - Please see Dave's link, that is the plan I used. I changed the vent to a slot vent. Just make the slot vent the same volume as Jim's vent.

Silverhairbp - I think this current plan will work for both A10 and A10.2. But you best check with Jim or Dave on this.

Dave, Jim, Mark - Thanks! I am really getting to love these cabinets and drivers now that I have fine tuned the damping, vent size, and spikes. The sound has really opened up once I had the combination right.
 
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