You are welcome! Thanks for the kind words but legend is the last thing that comes to my mindI assume you will be building them as front firing horns? I have not drawn up plans for them to be rear facing yet. Too bad foam core is so expensive in NZ.
Yes for now, they will be forward firing. My listening room precludes rear facing to a certain extent as it also doubles as my movie room and one corner has a sub and the other a built-in av rack.
Foamcore works out to $13NZ per 20x30" sheet. A sheet of reasonable ply (hardwood) is $50 for a 4x8x 1/2 "
Fringy,
Just wanted to make it clear that the driver chamber for the Peerless drivers needs to be reduced in volume from default to 1.2 liters for the above simulation. Wall it off or add volume filling material like blocks. Btw, the Vifa TC9FD can almost work as well at half the price.
Good luck!
Just wanted to make it clear that the driver chamber for the Peerless drivers needs to be reduced in volume from default to 1.2 liters for the above simulation. Wall it off or add volume filling material like blocks. Btw, the Vifa TC9FD can almost work as well at half the price.
Good luck!
Hey X, I was going to ask a related question. The Vifa and the Cornu are a great combination - but - do you think that is the optimum horn for the TC9DF? Did you look at a floor standing (straight/single) horn that comes anywhere close to optimizing the output based on the specs of that driver?
That last post may need some clarification. I believe so far, a horn design has been selected and then it's parameters are adjusted to make best use of what the driver is capable of. I'm just wondering if the process can be reversed by letting a software program predict an optimum horn configuration. That quite possibly could result in a very long (like the Queen's Trumpets ) flare, but maybe a single fold might make it practical.
I'm basing the question on an article I read stating the best bass speaker for, as I rember, a 20 Hz signal would be a concrete structure 16 feet long with a 1 foot square throat and an 8 foot square mouth. So given the specs of the Vifa - what would that look like and would the simplicity of construction improve the response?
) flare, but maybe a single fold might make it practical.I'm basing the question on an article I read stating the best bass speaker for, as I rember, a 20 Hz signal would be a concrete structure 16 feet long with a 1 foot square throat and an 8 foot square mouth. So given the specs of the Vifa - what would that look like and would the simplicity of construction improve the response?
Bob,
I don't have a program that automatically optimizes a horn based on driver specs. That is where experience and fiddling with the tuning manually comes in. Not to say it can't be done, and I have written auto-optimization codes for other things in the past. Basically, you have to define a parameter that quantifies the term "Good" (which is difficult to define with speakers). Once you have that, you write code that incrementally adjusts parameters to find the local maxima of the "Good" parameter. This is a highly non-linear relationship between the input parameters and what is considered good. It may not result in finding the best solution. But just playing around with the parameters and various alignments (MLTL, BLH, BR, MLTQWP, etc.) I think one of the best sounding enclosures for the Vifa TC9FD is the FH3-inspired back firing horn. It doesn't sim very well in AkAbak as the damping is critical and cannot yet modeled, but in MJK, it looked pretty good when Jim Shearer ran a simulation for me as a MLTQWP (mass loaded tapered quarter wave pipe - the Metronome) to approximate an FH3i. I will also say that it sounds very good in a MLTL similar to what I have built (but the FH3i wins due to the expansive sound from the back horn). My recent simulation of sticking it as a double driver in the BK12-inspired double-horn also looks pretty good. It is a very high Qts driver and more suitable for MLTL's than horns, and I just got lucky with how well it works in the FH3i. If you want to try something new with the Vifa, I suggest giving the FH3i a try. I listen to that speaker as my "favorite" sounding speaker everyday. Works great for jazz, vocals, and even classic rock like Fleetwood Mac.
I don't have a program that automatically optimizes a horn based on driver specs. That is where experience and fiddling with the tuning manually comes in. Not to say it can't be done, and I have written auto-optimization codes for other things in the past. Basically, you have to define a parameter that quantifies the term "Good" (which is difficult to define with speakers). Once you have that, you write code that incrementally adjusts parameters to find the local maxima of the "Good" parameter. This is a highly non-linear relationship between the input parameters and what is considered good. It may not result in finding the best solution. But just playing around with the parameters and various alignments (MLTL, BLH, BR, MLTQWP, etc.) I think one of the best sounding enclosures for the Vifa TC9FD is the FH3-inspired back firing horn. It doesn't sim very well in AkAbak as the damping is critical and cannot yet modeled, but in MJK, it looked pretty good when Jim Shearer ran a simulation for me as a MLTQWP (mass loaded tapered quarter wave pipe - the Metronome) to approximate an FH3i. I will also say that it sounds very good in a MLTL similar to what I have built (but the FH3i wins due to the expansive sound from the back horn). My recent simulation of sticking it as a double driver in the BK12-inspired double-horn also looks pretty good. It is a very high Qts driver and more suitable for MLTL's than horns, and I just got lucky with how well it works in the FH3i. If you want to try something new with the Vifa, I suggest giving the FH3i a try. I listen to that speaker as my "favorite" sounding speaker everyday. Works great for jazz, vocals, and even classic rock like Fleetwood Mac.
Understood - again the the variables trump simplicity. I'll investigate the FH3i. If I ever find the time I'd like to investigate the similarities between horn speaker flare and brass instruments like the tuba for some additional info. It would be fun though to experiment with a loooonnnng FC taper as my concrete budget is maxed out at the monent.
BTW: Does anyone know how ling a Klisphorn would be if unfolded to a straight pipe
BTW: Does anyone know how ling a Klisphorn would be if unfolded to a straight pipe
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Thanks x. I did see your annotation on your drawing about reducing the volumeFringy,
Just wanted to make it clear that the driver chamber for the Peerless drivers needs to be reduced in volume from default to 1.2 liters for the above simulation. Wall it off or add volume filling material like blocks. Btw, the Vifa TC9FD can almost work as well at half the price.
Good luck!
Just for fun, I found this while sorting through some downloads this morning. It's an example of what I meant by unfolding a Klisphorn. Then a Google search brought me right back to the forum. Wonder if something like this could be part of a two or three way scaled down FC project.
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Do a search for the Replicon Horn, it does a pretty good job of designing a traditional BLH [aka BVR, 'scoop' bin] using T/S, so I assume anyone with decent math skills [not me] can rearrange the formulas to get the driver specs.
Hopefully, someone will mod its Excel SS calculator to include this reverse engineering and post it somewhere for downloading for us math challenged folks.
GM
Hopefully, someone will mod its Excel SS calculator to include this reverse engineering and post it somewhere for downloading for us math challenged folks.
GM
Tractrix front horns in FC
I finally finished the tractrix front horns. It was easy to make using the 'score the concave curved side' technique. The hard part was coming up with the pattern - I did it with regular paper by trial and error to get close, then the final foam still needed some trimming. The resulting horn has a 4 in x 4 in throat and a 13 in x 13 in mouth with a 4.5 in length. I did a quick test by taping it to the front of the FH3-inspired FC speakers and wow, you really notice the gain in mids and highs from a distance away. Also the presentation was wider, you can walk around more and still hear the highs clearly. The trick is to make the brace first with the correct profile, hot melt the horn panel to that first. Make 4 of those sets and then glue the seams together one by one. If anyone is interested in the pattern, I can scan that and post it.
I finally finished the tractrix front horns. It was easy to make using the 'score the concave curved side' technique. The hard part was coming up with the pattern - I did it with regular paper by trial and error to get close, then the final foam still needed some trimming. The resulting horn has a 4 in x 4 in throat and a 13 in x 13 in mouth with a 4.5 in length. I did a quick test by taping it to the front of the FH3-inspired FC speakers and wow, you really notice the gain in mids and highs from a distance away. Also the presentation was wider, you can walk around more and still hear the highs clearly. The trick is to make the brace first with the correct profile, hot melt the horn panel to that first. Make 4 of those sets and then glue the seams together one by one. If anyone is interested in the pattern, I can scan that and post it.
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Thanks Prez! You are the master of the beautiful Cornu, and by all accounts you have made more of them than anyone - making you the master Cornu FC sculptor!
How are those W4 TB Bamboos in the 22 in x 4 in Cornus doing? Do you ever plan on making measurements using an inexpensive mic and Holmimpulse or something similar? I am curious to see how my sims of the Cornu match with measurements.
How are those W4 TB Bamboos in the 22 in x 4 in Cornus doing? Do you ever plan on making measurements using an inexpensive mic and Holmimpulse or something similar? I am curious to see how my sims of the Cornu match with measurements.
I remember your horn. When you say too aggressive, does that mean there is HF falloff? It's easy to scale plan with printer prior to cutting to get your size.