acousticoil

[akniffen]

Mike Johnson wrote that he experimented with his PT-15 by adding venturi tubes to his tuning, 3rd and 4th slides with success. I would like to know as much detail as he would be willing to provide, but his contact information is missing in his Tubenet profile. Can anyone help?

[imperialbari]

As I remember the said device it is a square mesh rolle to fit inside tubing.

There have been reports of tube inserts having a positive effect, but that has been about correcting what may be considered design flaws.

The Geyer design of French horns is based on on an old German design tradition of horns with a different placement of the shift valve compared to the equally German based Kruspe design. Geyer instruments also tend to have a more slender throat.

Almost all horn players pull their valve slides the same amounts when it comes to Geyer horns. And many of these horns tend to have a non-speaking high Bb (concert Eb) on their Bb side.

Following an earlier discussion about acousticoils a horn player/repairman tried inserting tubing of the same dimensions as the male slide branches to fill the gaps left by the common slide pulls. And the missing high Bb suddenly became playable.

Some tubas like my 1999 Besson 981 Eb have male slide branches with very thick wals. I don’t pull valve slides, but pulling the main slide cannot be avoided. I don’t know whether it is technically possible, but I would want the first slide branch being female like with the Bach trumpets with reversed tuning slides.

Klaus

[SousaSaver]

I am skeptical of almost ALL products like this. I mean stuff that claims to effect your tone but doesnt have seem to have any grounding in science. I know the claim, I am just skeptical.

I suspect that the testimonials are a result of a phenomenon called confirmation bias, which is a tendency for people to favor information that confirms their preconceptions. If someone tells you that item A will do X, your brain will work to make X happen.

I worked for a guy that sold stuff for a major manufacturer. He was displaying at a major show in a windy city and had a fellow come up and try out trumpets. After trying out a few trumpets, he offered the fellow trying horns to try his new "tone enhancer." After hanging the tone enhancer from the main tuning slide water key, the player noted that his sound was darker, more centered and the slotting was better. What was the "tone enhancer"? A heavy key chain.

These are just my opinions, I could be wrong.

[akniffen]

I believe Imperialbari is correct, but my question does not involve the original topic - accousticoils.

I have seen venturi-like additions/corrections/whatever to horns that have been productive. One metioned in this thread (by Lee Stofer?) is the usual York set up, where the small side of the tuning slide is smaller than the fourth valve tubing/piston. The new Yamaha York model does this, as does the CSO York, if I remember correctly. There is a new Miraphone 6/4 BBb coming out soon whose prototype had a venturi-type adjustment to the fourth slide tubing. Mike Johnson mentioned trying that in his PT-10 3rd, 4th and 5th slides with noticable improvement. I have tried 'sleeving' down the small side of my tuning slide and noticed some improvements but more detrimental effects in the sound (not a great fit?). Having tried similar/better things with positive effect more recently (and being aware of the possibility of being fooled by my own desires), I believe it is worth pursuing and am seeking more comments from those with experience, but more to the point, does anyone know this Mike Johnson fellow?
Tony Kniffen

[Doug Elliott]

The last I knew, Mike Johnson was in England, in the Manchester area.

I am not a fan of the coils, but certain instruments may have areas where the tubing is "too big" and causing intonation or response issues. A bad desgn like that, possibly from nothing more than careless assembly, could benefit from a little "correction" in the right place, if you can find the right place.

[Wyvern]

Tony, I have sent you PM

Jonathan

[toobagrowl]

I have been experimenting with cut plastic rectangles in my ancient rotary BBb. I had a couple of old empty bleach jugs, cleaned them inside-out and cut the pieces. The rotary BBb has a huge bore, so I rolled up a few pieces (3 each) and put them in both ends of the main tuning slide. Seems to give a touch more resistance and makes a *slight* improvement in stabilizing the response. I put pieces in the second, 3rd and 4th slides too. The 4th valve CC is not as easy to 'blat' now like before, which is good.
I am still experimenting with them.

Months ago, I cut a piece from a plastic "ONES" prunes tube and really didn't notice a difference when used. I would recommend using old bleach jugs or detergent jugs because the plastic is thicker and more durable. Cut several pieces. The plastic in soda bottles or even milk jugs is too thin to make much difference, imo.

$40 is ridiculous for a piece of plastic when you can make several pieces yourself and get similar - possibly better - results.

[Phil Dawson]

I use one in both my Miraphone 1290 and my Conn 3J. Do they work wonders and improve my playing by 50%? NO. I do feel that the horns play a bit better with them in. As for the inventor Don Novy he is a true gentleman. He taught Junior High band for many years in Denver and I was lucky enough to play a quintet gig with him (on trumpet) one time. I would not worry one bit about getting your money back from him if you don't like the product. That being said why not give it a try? You might like it, you might hate it, or it might do nothing at all for you just please don't judge something before you try it especially when you can do so for free. Phil

[iiipopes]

How much is due to the velocity of the compression wave through the actual lessening of the bore, and how much is due to damping a resonance at an antinode that can leech the tone out of a particular note?

[Phil Dawson]

I don't have a clue it just seems to make my horns sound a little bit better, Phil

[ghmerrill]

I know I am a bit late to this thread -- which I have followed with interest and no small degree of skepticism (thinking of things like those magnets that you apply to your fuel lines to "align" the fuel molecules and enhance your gas mileage).

However, finally I couldn't resist. I was also struck (was no one else?) by the odd similarity of the acousticoil to plastic shotgun wads. It turns out that a 12 ga. wad is just about the right size for my tuba, but further investigation showed that this line of R&D was a dead end since it required rather extensive wad modification. However, once thinking along that line, it next occurred to me that the plastic body of the shell case itself presented an interesting opportunity for experimentation.

Thus: Take one 12 ga. (empty!) shotgun shell and saw off the brass base, leaving you with a plastic cylinder that narrows at the one end due to the crimp. (I used a Japanese dozuki saw -- which I recommend highly -- and a Winchester AA shell case. But I don't think either of these choices is critical.) Now take your high quality shears and cut the shell case fragment longitudinally (so you can roll it to a smaller diameter if necessary, and so it will also act as a "spring" in holding the device in your tubing). For small bore horns you may need to trim the shell size down as you do this so it will fit in the smaller bore horn. The result fits quite perfectly in my .787" bore Cerveny. I originally stuck it in the second valve slide hoping it would miraculously fix my intonation problem. Alas, it did not.

Then I stuck it in the downstream side of the tuning slide with the crimp pointed downstream. Amazing! Suddenly everything was in tune and I could play in tune two octaves above the staff!! ..... Well, okay, that's all a lie. But ...

It definitely affected how easily the low register comes out, and articulation in that register. Since I now have a total of seven mouthpieces to experiment with (three of mine and four on loan), I tried it with all of them. Same result. With the pseudo-acousticoil (trademark?), the low register (like F1 and below) comes out much more easily and smoothly. I originally thought sure it was some kind of placebo effect, or that it wouldn't appear with one mouthpiece or another. Of course it does seem to be true that mouthpieces that render the low register more accessible seem to benefit a bit less, and I have made no attempt to quantify any of this, but I'm convinced it's real.

I think the next step in this research program is to try a 20 ga. or 28 ga. shell casing in my crazy oval euph. For larger bore horns,10 ga. shell casings may be necessary. I don't have any of those. I should probably work up a "use patent" for this.