TubaForum.net

jtm wrote: ↑Fri Sep 30, 2022 2:29 pm

bloke wrote: ↑Sat Sep 17, 2022 7:26 am Finally vented the valves.
Suddenly, I don’t have to nurse any slurs.
I’m liking this instrument more and more.
...

What does this mean?

With well sealed, non-vented valves you can get slight back pressure from pushing the valves if there is any air pressure difference between the sealed branch tubing the outside air. At times this can be enough of a bump to roughen up your slur in a noticeable way. Vented valves prevent this because the branch tubing is hooked to the outside air so there won't be any pressure differences.

Inkin wrote: ↑Fri Sep 30, 2022 3:34 pm ...
With well sealed, non-vented valves you can get slight back pressure from pushing the valves if there is any air pressure difference between the sealed branch tubing the outside air. At times this can be enough of a bump to roughen up your slur in a noticeable way. Vented valves prevent this because the branch tubing is hooked to the outside air so there won't be any pressure differences.

Thank you! My slurs may be bad enough anyway that I just never noticed this. And now I won't worry as much because my 188 is already vented.

I post an awful lot. Let’s see if someone else can explain this better than I can.

It’s like throttle adjustments while shifting gears to make the gear changes smoother.

matt g wrote: ↑Fri Sep 30, 2022 4:19 pm It’s like throttle adjustments while shifting gears to make the gear changes smoother.

…and venting valves might sort of be a kin to some computerized whatever that might possibly make these adjustments more automatic (perhaps done by the fuel injectors for the driver) or less essential (??)

^^^
I just offered a terrible analogy, which is why I was shying away from answering in the first place

bloke wrote: ↑Fri Sep 30, 2022 4:45 pm

matt g wrote: ↑Fri Sep 30, 2022 4:19 pm It’s like throttle adjustments while shifting gears to make the gear changes smoother.

…and venting valves might sort of be a kin to some computerized whatever that might possibly make these adjustments more automatic (perhaps done by the fuel injectors for the driver) or less essential (??)

^^^
I just offered a terrible analogy, which is why I was showing away from answering in the first place

Or just the idealized version of a CVT where it just needs throttle input and the change in ratio happens smoothly.

The fourth rotor is the same bore but a larger diameter with more cavity size in the rotors. My suspicion is that it doesn’t make a lick of difference and slightly slows down the fourth rotor.

The arm length surely makes no difference whatsoever.

I’m making quite a few little changes to this instrument as I always do to all of my instruments.

The design of the instrument as it is delivered from the factory is superior – in my view – to the M-W 195, way easier to play in tune than a 197, and much better sounding than the somewhat new 497.

I could have picked up several 195 instruments over the years for less than I paid for this, but waited (and waited and waited) for one of these to be priced in my preferred range and also in excellent condition.

Make no mistake: playing an extra-large B-flat requires more anticipation than playing a medium large, large, or extra-large C instrument… off but the payoff is the sound, which sounds like a really fine contrabass (string bass) player pulling his bow across his open strings…except (again) mic’ed and amplified with a 1960’s Ampeg Portaflex bass amp.

Bloke, could you post a pic of where to drill vent holes in rotors? I’m getting used to my 190 with 20’’ bell and I think it could benefit from venting. My tech is experienced, but not in this particular procedure. I may end up driving to Tennessee, but trying to avoid

MikeMason wrote: ↑Sat Oct 01, 2022 9:47 am Bloke, could you post a pic of where to drill vent holes in rotors? I’m getting used to my 190 with 20’’ bell and I think it could benefit from venting. My tech is experienced, but not in this particular procedure. I may end up driving to Tennessee, but trying to avoid

There’s an entire thread:

viewtopic.php?t=1267

MikeMason wrote: ↑Sat Oct 01, 2022 9:47 am Bloke, could you post a pic of where to drill vent holes in rotors? I’m getting used to my 190 with 20’’ bell and I think it could benefit from venting. My tech is experienced, but not in this particular procedure. I may end up driving to Tennessee, but trying to avoid

The red-dot spot might actually be better, but anywhere about halfway between the two circuit-adding knuckles that exposes the passive rotor cutout to the atmosphere is good. Realize that the knuckle tubing itself is probably at least .6mm thick, so I could drop at LEAST 2mm below a line defined across the outside tops of the two knuckles. (In the picture, I attempted to draw the blue line across to the tops of the BORES of those knuckles.

Most people remove their rotors, but I back off - towards the end of drilling, roll the drill bit around the inside of the hole - to knock off the burr, take the tuba outside/remove the slides/jet water through the valveset with the main slide removed (to jet out brass filings), dump copious amounts of oil into the rotors, and work what might remain of any burrs out with the rotor bodies themselves. Again, I'm lazy, and some will say that I'm ruining the rotors, but - when I eventually remove the rotors for some sort of service - I never see any extra marks on them at the vent level. Having just done this to the 5 rotors on my model 98 (with very crisp/like-new rotors - NOT the pictured tuba, which is some old picture I found in my computer) it required very very turns (again: with copious amounts of oil) to smooth out their action. They are neither sticking nor hissing, and I've not removed any of them from the instrument.

@bloke what size drill bit do you use for that?

arpthark wrote: ↑Sat Oct 01, 2022 11:58 am @bloke what size drill bit do you use for that?

I'm thinking that those sitting around here currently (not dull enough - yet - to throw in the trash and replace) are a sixteenth inch in diameter and a foot long. I believe they cost about three and a half bucks each.

I've seen larger and smaller holes...

Everything works if not too large, too small. nor located outside of thoughtfully-chosen parameters.

-------------------------------------------

I have seen some astonishingly idiotically-drilled holes (according to the owner of the instrument, by someone highly regarded. I'm not saying - neither publicly nor privately, so don't ask). Thankfully, they were drilled at the correct longitude, so they didn't ruin the instrument (merely "stupided it up").

matt g wrote: ↑Fri Sep 30, 2022 4:49 pm

bloke wrote: ↑Fri Sep 30, 2022 4:45 pm

matt g wrote: ↑Fri Sep 30, 2022 4:19 pm It’s like throttle adjustments while shifting gears to make the gear changes smoother.

…and venting valves might sort of be a kin to some computerized whatever that might possibly make these adjustments more automatic (perhaps done by the fuel injectors for the driver) or less essential (??)

^^^
I just offered a terrible analogy, which is why I was showing away from answering in the first place

Or just the idealized version of a CVT where it just needs throttle input and the change in ratio happens smoothly.

If i understand a CVT, that would be like having a trombone slide in the mix.

Pretty sure vented valves is like having a better clutch. Less of a thump when you engage the new note. So synchromesh? And that analogy holds up a little under a closer look, as sound propagation changes with the air pressure.

But to carry the analogy too far, did early BAT players need to learn double clutching? What would be the metaphorical skill equivalent to starting on a hill?

humbell did the best job.
“Double clutching” (even though synchromesh gears are in place) might be analogous to “legato tonguing” - and doing so EVEN THOUGH tubas have valves.
I know of one particular teacher of tuba - who is quite widely known and well thought of - who insisted that all students “legato tongue”. I tend to suspect (??) it was because the teacher - in their own playing stumbling blocks - could not slur very well.

Bloke, I remember you praising this horn and sounding great on it at ITEC Indiana when they were fresh out of the factory.
I was the one whose Rusk franken f took a tumble when you were fitting bloke washers. it may have been a stroke of luck though, because it seemed to feel a bit more resonant after you kindly offered to magnet roll out the slightly dented top bow, although the better alignment probably played a role too
Anyhow, I had a feeling that horn was always meant to be a part of your arsenal
https://tenor.com/bVpNr.gif

I remember all of that…!!
…and I also remember that Baadsvik guy hanging over me when I was trying to play that instrument and listen to it. It was a little bit distracting, but I try to never let myself become too distracted.

It’s funny how someone picking up an instrument and playing it in the middle range at mezzo forte tends to attract the attention of some types of players.
As far as whether I should’ve bought it right then or not for $12,000 or $13,000 or whatever it was… that was twice as much money (spending-power-wise) as it is today, and that’s really why I kept my money in my pocket. $6000 at that moment in time…?? I would’ve walked into a restroom stall, pulled that much out of my pocket, and bought it on site.

bloke wrote: ↑Sat Oct 01, 2022 5:16 pm I remember all of that…!!
…and I also remember that Baadsvik guy hanging over me when I was trying to play that instrument and listen to it.

Yeah, we're both remembering the same moment, haha! It seems the one night of alcohol poisoning at that conference didn't do too much dain bramage, although I can't recall which horn I was trying at the moment.

The Rudy 5/4 cc Wilk had at his booth is deeply ingrained in my memory, though. Felt like playing organ pedal pipes in the low range

I may soon get myself a BBb too, albeit a cheap 3 banger to work on improv skills for fun as a hobyist after giving up music as a career 6 or so years ago and starting a career in IT... hence the recent return to lurking and posting

I’m thinking that I might’ve had my Rudy 5/4 there for some reason…the one with interchangeable mouthpipe tubes. I’m thinking that Tony Kniffen played it, and said he didn’t like the more normal-sized mouthpipe tube (It wasn’t for sale at that time.)
The tuba - that the elephant had been borrowing - was there, as well as a satin-silver Holton B-flat.

Ahh, it would appear there was some dain bramage. I remember now it was your Rudy I was playing sitting at Wilk's booth. I have no use for such a horn now, but that experience and listening to Andy Smith play a 3/4 cc at a guest recital have made the Rudy 3/4 one of the horns I'd most like to own some day

TheDoctor wrote: I remember now it was your Rudy I was playing sitting at Wilk's booth.

Were are you wearing your long johns in Wilk’s Booth?