mp9 said:
FYI, as a general (though not invariable) rule, a 'horn' and a BVR are one and the same -it's simply a matter of degree, and goal. I know what you're referring to though, and I should hope so -the FE166ES-R, uncorrected, will prefer a long-path design, assuming you want to take it low.
would a flush mounted supra baffle ( http://www.diyaudio.com/forums/attachment.php?s=&postid=1577145&stamp=1217806206 ), function better if extended to the bottom of the cabinet, rather than having the front panel overlap the bevel and trailing edge of the s.b.?
thanks guys that helped, i'm reconsidering them as i'm under the impression a well designed horn will out perform a bvr.
what kind of negative problems result from not using the rear deflector?
Depends on the driver. There is little (if any) TL action in a BVR, a small mouth long path BLH depends on the initial TL action to produce the lowest notes and the actual horn action rolls in (if properly designed) at the first roll off of the TL action. Its either that or design for a mouth size that you can park a small car in.
There is greater cone control in a BLH (designed correctly) as there is a given loading on the rear of the cone. It all depends on the driver and the application. Given a driver of around .35 Qts i would go for a BVR , given a driver of around .2 Qts i would go for a BLH. This was one of the problems i encountered in the design of the A126. I based the design on the factory stated T/S parameters. If i had actually measured the actual parameters then the design would have changed and included a much larger filter chamber volume than initially designed and Dave and Chris would have not found the falts that led to a larger chamber volume and the SB. As the chamber got larger the BW of the horn action went down and the SB action rolled in as the lower horn action rolled off.
what kind of negative problems result from not using the rear deflector
Corner loaded or even wall loaded there is a wave front reflected from the wall , much more in a corner, that re-enters the mouth and causes cancellation/re-enforcement of the wave front being developed in the horn path. This leads to a greater lumpy (love the tech terms) FR curve. This is a problem that i noticed when a BIB is used, note just a sim not an actual function test. Now take a BIB and angle the exit wave so a reflected wave is lessened and expand the final flare and i believe the FR curve will improve.
would a flush mounted supra baffle ( http://www.diyaudio.com/forums/attachment.php?s=&postid=1577145&stamp=1217806206), function better if extended to the bottom of the cabinet, rather than having the front panel overlap the bevel and trailing edge of the s.b.?
Nope! however it would look less like a lollypop.
ron
what kind of negative problems result from not using the rear deflector?
Depends on the driver. There is little (if any) TL action in a BVR, a small mouth long path BLH depends on the initial TL action to produce the lowest notes and the actual horn action rolls in (if properly designed) at the first roll off of the TL action. Its either that or design for a mouth size that you can park a small car in.
There is greater cone control in a BLH (designed correctly) as there is a given loading on the rear of the cone. It all depends on the driver and the application. Given a driver of around .35 Qts i would go for a BVR , given a driver of around .2 Qts i would go for a BLH. This was one of the problems i encountered in the design of the A126. I based the design on the factory stated T/S parameters. If i had actually measured the actual parameters then the design would have changed and included a much larger filter chamber volume than initially designed and Dave and Chris would have not found the falts that led to a larger chamber volume and the SB. As the chamber got larger the BW of the horn action went down and the SB action rolled in as the lower horn action rolled off.
what kind of negative problems result from not using the rear deflector
Corner loaded or even wall loaded there is a wave front reflected from the wall , much more in a corner, that re-enters the mouth and causes cancellation/re-enforcement of the wave front being developed in the horn path. This leads to a greater lumpy (love the tech terms) FR curve. This is a problem that i noticed when a BIB is used, note just a sim not an actual function test. Now take a BIB and angle the exit wave so a reflected wave is lessened and expand the final flare and i believe the FR curve will improve.
would a flush mounted supra baffle ( http://www.diyaudio.com/forums/attachment.php?s=&postid=1577145&stamp=1217806206), function better if extended to the bottom of the cabinet, rather than having the front panel overlap the bevel and trailing edge of the s.b.?
Nope! however it would look less like a lollypop.
ron
REC1 said:
thank you that rule's out the iris as zaphaudio measured a totol Qt of .2213 for the 166es-r http://www.zaphaudio.com/6.5test/compare.html
interesting to hear why the SB was used in the a126 but why continue to do so for the a166 and frugal horn if it could've been designed with a larger filter chamber?
BTW since it's already been suggested by others here, can those of us with 166esr's chip in and paypal you to design a blh specifically for them?
interesting to hear why the SB was used in the a126 but why continue to do so for the a166 and frugal horn if it could've been designed with a larger filter chamber
You have it backwards. As the filter chamber gets larger the BW of the horn action goes down, The SB action (name coined by Dave) rolls in as the horn action rolls off. Its a combined action. In the old days of huge baffle BLHs this was not a consideration. As the baffle size went down the baffle step went up in frequency. All the SB accomplishes is to bridge the frequency gap between the horn action and the baffle action.
I truly wish i had more time to devote to audio, but i really dont.
I am still a fan of OBs and the simplicity of the actions. To me i perfer a 2 way with a dedicated bass driver and a seperate WB.
MKs OBs are still in my apt and doing service, i will come up with something for my home in SC probably on the lines of a BVR for the low end and either an OB with a rear deflector or a waveguide/horn WB for the mids & higher.
(gee sounds kinda like an Altec mdl 14-19 huh?)
ron
You have it backwards. As the filter chamber gets larger the BW of the horn action goes down, The SB action (name coined by Dave) rolls in as the horn action rolls off. Its a combined action. In the old days of huge baffle BLHs this was not a consideration. As the baffle size went down the baffle step went up in frequency. All the SB accomplishes is to bridge the frequency gap between the horn action and the baffle action.
I truly wish i had more time to devote to audio, but i really dont.
I am still a fan of OBs and the simplicity of the actions. To me i perfer a 2 way with a dedicated bass driver and a seperate WB.
MKs OBs are still in my apt and doing service, i will come up with something for my home in SC probably on the lines of a BVR for the low end and either an OB with a rear deflector or a waveguide/horn WB for the mids & higher.
(gee sounds kinda like an Altec mdl 14-19 huh?)
ron
haven't heard those but i did hear the altec 604e driven by a OTL amp and really like them. if i were to do a o.b i'd want to use a driver that can run without the need for a additional bass driver such as the phy's. possibly the seas exotic however both are very expensive, too bad madisound doesn't run a 15-20% off sale.
if i were to do a o.b i'd want to use a driver that can run without the need for a additional bass driver such as the phy's. possibly the seas exotic however both are very expensive, too bad madisound doesn't run a 15-20% off sale.
Good luck. Even Hawthornes driver needs some form of LF boost, and its a coiax which in my mind is a two way.
To get the performance from the A166 i had to use every trick i could concieve and about one solid month of sims (after the software had developed) to get what i could. I do not have the easy software like Martin where you punch in parameters and get a result. Its more a step by tiny step throught the process and very time consuming.
I set out to get the maximum i could from the Fe166 and the A166 is as close as i could get without major performance losses somewhere in the FR spectrum. Its as close as this tired old Texan can get. Perhaps someone else can do better.
ron
Good luck. Even Hawthornes driver needs some form of LF boost, and its a coiax which in my mind is a two way.
To get the performance from the A166 i had to use every trick i could concieve and about one solid month of sims (after the software had developed) to get what i could. I do not have the easy software like Martin where you punch in parameters and get a result. Its more a step by tiny step throught the process and very time consuming.
I set out to get the maximum i could from the Fe166 and the A166 is as close as i could get without major performance losses somewhere in the FR spectrum. Its as close as this tired old Texan can get. Perhaps someone else can do better.
ron
Ron, would you have any thoughts or comments on this OB design? I know this thread topic is not titled OB, but as they have come up in the thread, I thought maybe I could ask?.. http://www.enjoythemusic.com/Magazine/equipment/0107/diy_loudspeaker_project.htm
Btw, I doubt anyone will be taking the 166 farther in any BLH design than your A166, and if at all, the gains would be small... The only thing that may appeal more in a different design ,would be the SB WAF thing going on.. Dave
Btw, I doubt anyone will be taking the 166 farther in any BLH design than your A166, and if at all, the gains would be small... The only thing that may appeal more in a different design ,would be the SB WAF thing going on.. Dave
mp9 said:
'bout the same as where I was last post, unfortunately. Work continues to press my spare time to the limit, and BAF'08 is looming on the horizon... I have a few things to pull together in advance of that. Just last night, I finally got my F120A's assembled into their little BR boxes. Sounding quite good so far, but they clearly need BSC, which I haven't got to yet. Need to get a rough measurement for that.
I'll try and get back to the A166 plans again this weekend or next.
Tech term: Acoustic Emission.
OK so i started thinking (RUT RO). The endless debate on Enable and the total answer was never really finalized.
The Acoustic Emission (AE) of the cone, i dont believe, was ever addressed. This could be the answer. The dots break up the skin emissions that are produced by AE.
Just a thought.
ron
OK so i started thinking (RUT RO). The endless debate on Enable and the total answer was never really finalized.
The Acoustic Emission (AE) of the cone, i dont believe, was ever addressed. This could be the answer. The dots break up the skin emissions that are produced by AE.
Just a thought.
ron
serenechaos said:
The coax -- i have a customer set. Darryl never did send me a full set, not understanding that the tweeter needs doing too (and it turns out he didn't know that a pro tweeter could be dissassembled to change the dome).
The driver is an assembly custom built out of the Eminence parts bins.
It is a painful process to do a set of these. Mostly because they are so big. But i almost have the customer set done (thank goodness for his patience).
dave
dave:planet10 said:
That's funny, but not suprising...
"Manufactures" whose knowledge base extends to the limits of re-naming, re-labeling and putting products others make in boxes...
I'll try & not go there...
Didn't know you had been treating compression driver domes.
I have a pair of PB850s & a pair of 475s I was thinking of experiimenting with shrinking an enable pattern on...
Are you using the same paint, or something thinner/lighter?
Are you just doing the pattern, or coating them with anything?
(Like aquaplas, etc.)
Or is this proprietary, or should I ask Bud, etc?
I have a question for Ron:
I'm trying to reconcile the horn dimensions to try and recreate the original horn design as accurately as possible. The A166 plans on Planet10's site show two designs. One is the A166 with smooth curves (built up from a laminated stack of CNC cut material). The second part of the plans is for the A166 built the more conventional way with plywood panels, so the curves are broken down into piecewise straight sections. Can you tell me which of the two more accurately represents the correct (simulated design) dimensions? I am assuming it is the curved version.
If my assumption is true, then the version built from flat sections of ply is an approximation of the smoothly curved horn taper... in which case, if I were to overlay the 'exact' curves over the piecewise version, how should the straight sections line up with the overlaid curves? Should the straight sections be tangential to the precise curves, or partly inside / partly outside the circle so that the horn cross-sectional area averages out around the bend?
Perhaps a diagram would help clarify what I mean. I am going to work on the CAD plans some more, to add the curved version. That way I can overlay the drawings and compare. But any hints as to how they should line up relative to one another would be much appreciated!
I'm trying to reconcile the horn dimensions to try and recreate the original horn design as accurately as possible. The A166 plans on Planet10's site show two designs. One is the A166 with smooth curves (built up from a laminated stack of CNC cut material). The second part of the plans is for the A166 built the more conventional way with plywood panels, so the curves are broken down into piecewise straight sections. Can you tell me which of the two more accurately represents the correct (simulated design) dimensions? I am assuming it is the curved version.
If my assumption is true, then the version built from flat sections of ply is an approximation of the smoothly curved horn taper... in which case, if I were to overlay the 'exact' curves over the piecewise version, how should the straight sections line up with the overlaid curves? Should the straight sections be tangential to the precise curves, or partly inside / partly outside the circle so that the horn cross-sectional area averages out around the bend?
Perhaps a diagram would help clarify what I mean. I am going to work on the CAD plans some more, to add the curved version. That way I can overlay the drawings and compare. But any hints as to how they should line up relative to one another would be much appreciated!
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