Yamaha 6xx valve

[jchiang9]

Curious if anybody knows if the Yamaha large bore tenors rotors from the 6xx(x) horns are the same as the 8xx horns.

[Burgerbob]

I'm pretty sure they've been largely the same valve since the 80s on all their horns. But which two instruments specifically?

[Bach5G]

The Bousfield 682B had an oversize valve that was unique to that horn. I don’t think it ever showed up on any other Yam horns.

[Burgerbob]

Yes, other than the weirdo valves (B valve, V valve) the rotors have not changed a lot for a long time.

[BGuttman]

Yes, other than the weirdo valves (B valve, V valve) the rotors have not changed a lot for a long time.

To be honest, there wasn't much need to change. In 1985 when I bought my 682G I tested it against a Bach 42B and found it to be much more open.

Main difference I've seen on Yamaha valves is the older pro and current student horns use a string linkage while the Pro line (going back to the 682/684) use a series of rods.

[Burgerbob]

Yes, other than the weirdo valves (B valve, V valve) the rotors have not changed a lot for a long time.

To be honest, there wasn't much need to change. In 1985 when I bought my 682G I tested it against a Bach 42B and found it to be much more open.

Yup, they got it right the first time.

[tbonesullivan]

I believe that the YSL-882IIOR and its predecessor, the YSL-882OR, have a "Balanced Response Rotor"

The balanced response rotor system helps air release evenly into the F-attachment slide creating a smoother transition from the Bb open horn to the engaged F-attachment

I believe it is some type of internal venting.

[jchiang9]

I was mostly curious because I do like the valves on the 882OR and on the 882O in particular. Was curious about the 6xx valves for potential projects on the cheap!

[Matt K]

Given that some of the 6xx series are .547 bore (646 comes to mind), there are certainly some differences between the 8xx series which are all .562 for tenors (no 8xx series medium bore yet right?).

[sirisobhakya]

Given that some of the 6xx series are .547 bore (646 comes to mind), there are certainly some differences between the 8xx series which are all .562 for tenors (no 8xx series medium bore yet right?).

Surprisingly, the valve casing is the same across the board for tenors AND basses at least for 600 and 800 series. The valve cap of YBL-822G (bass) fits the casing of the YSL-820GII (tenor) and the YBL-612 (another bass). I haven’t tried it on the YSL-356G (small tenor), though.

I believe that the YSL-882IIOR and its predecessor, the YSL-882OR, have a "Balanced Response Rotor"

The balanced response rotor system helps air release evenly into the F-attachment slide creating a smoother transition from the Bb open horn to the engaged F-attachment

I believe it is some type of internal venting.

According to a photo of the 882OR valve core in Japanese catalogue, it is vented.

[hornbuilder]

Just because a valve cap will fit both tenor and bass casings, does not mean that the casings themselves are the same. They have the same outer diameter, and thread spec. I use the same caps/retaining rings on both tenor and bass casings, but the tenor casings have .562" knuckles, and the bass casings have .594" knuckles. And obviously the rotors match the casings.

[Matt K]

Yeah the valve covers are pretty universal for Yamaha horns. You should find the valve cover works on a 356 as well. The 356 I had measured .530 tubing. They obviously have the capability of producing high quality rotors of an assortment of bore sizes but I am not aware of any more differences across the various models, other than as others stated, some of the marketing indicates the direction rotates on some models is reversed from what it normally would be. I dont' really remember which ones have that, or why that is a desirable trait.

[Finetales]

Previous threads indicate that the 646 (.525") has a .547" F loop.

[sirisobhakya]

Yeah the valve covers are pretty universal for Yamaha horns. You should find the valve cover works on a 356 as well. The 356 I had measured .530 tubing. They obviously have the capability of producing high quality rotors of an assortment of bore sizes but I am not aware of any more differences across the various models, other than as others stated, some of the marketing indicates the direction rotates on some models is reversed from what it normally would be. I dont' really remember which ones have that, or why that is a desirable trait.

That is the 830, when advertised against older models (613H and 813UG). The older models have the Gb valve that rotates away from the air stream, exposing the “partition” between valve passage.

It makes some difference only in legato. I haven’t had a chance to play either 613H or 813UG, but I had a rotary baritone horn that has 3rd valve rotating away from the air stream, and the difference while playing legato is markedly different.

The 835 no longer advertises this point. But it has bored-out rotor, which obviously makes more obvious difference.

Another related advertising is the “air flow direction” on the YSL-825, the one with weird-looking valve knuckles. Supposedly, the air flowing in the same direction in both main loop and F loop makes a difference. There is an essay in the Japanese Yamaha website detailing development process, in which Kiwata Akira, the collaborating artist, explains that he liked the blow of Yamaha V valve, which has the F branch air flow in the aforementioned direction, so he specifies that the 825 has the same air flow.

Does it help? I have tried a 825 once. Good horn, but the effect of the valve is not obvious. I will try to try it against the 882O and OR if I have a chance when I am in Japan this Christmas.

[jchiang9]

Previous threads indicate that the 646 (.525") has a .547" F loop.

Do you mean the valve section measures .547" or are the same as the .547" horns with .562" for the 646?

[Matt K]

Previous threads indicate that the 646 (.525") has a .547" F loop.

Do you mean the valve section measures .547" or are the same as the .547" horns with .562" for the 646?

All 525 F attachment Yamahas, to the best of my knowledge, are .547" bore through tue tubing, smaller than the .547 bore models, which have .562" tubing. The 500/525 models are .530. Or at least all the ones I've measured, which is limited to the 356 model. (I know they made other 500/525 but I belive all of them are sans F attachment).

[tbonesullivan]

Yamaha is VERY big about reusing parts, which is definitely not a bad thing, especially when you have a 30 year old horn and are looking for parts. Right now I'm trying to locate the "end" handle for my 90s maroon case, as the metal steel piece inside the faux leather finally gave way at one end. I think they still use that same handle on some other cases, so it's just a matter of tracking one down.

Anyway, to get back on track, I do remember the whole thing about how about with a traditional rotor, one direction results in a more smooth slur than the other. I'm not sure if this occurs because of air build up or something else, but I definitely remember hearing people talk about getting Duo Gravis horns modified to reverse the turning direction of one of the valves, maybe the 1st valve, as when looking at the left side of the horn, it rotates counter clockwise.

However, thinking back, I'm pretty sure that changes have definitely been made over the years to the 600 series valves, at least on the bass trombone. Older 611 and 612 trombones had valves with brass casings, while newer ones have nickel casings. The valve covers also look different, though I don't know if internally they are any different.

[bassclef]

Do you mean the valve section measures .547" or are the same as the .547" horns with .562" for the 646?

All 525 F attachment Yamahas, to the best of my knowledge, are .547" bore through tue tubing, smaller than the .547 bore models, which have .562" tubing. The 500/525 models are .530. Or at least all the ones I've measured, which is limited to the 356 model. (I know they made other 500/525 but I belive all of them are sans F attachment).

FWIW - I just measured one of the f-attachment slides on my 640 and it was .547.

Also, I use a set of those heavier 822 valve caps on my YBL-620G. I have tried to put them on my 613H and they don't fit. It seems like the threads catch and I can rotate the cap exactly one half turn and then it binds up. Don't want to force it any further. Same story with the valve on my 621 and with both on my early 613 with brass casings.

[Burgerbob]

I have 822 caps on my Japan-only 8130G. Perfect fit.

[sirisobhakya]

822 on 612, 830, and even YSL-820 (tenor) is perfect fit. The 620G is the continuation of 612, so it should, at least in theory, fit. Not sure what happened to yours…

[bassclef]

Yeah, I was a little surprised that those caps don't fit on the three horns I mentioned above. They all stop rotating in exactly the same spot. Perhaps if I just use a bit of force to get it past that point it'd be fine, but I am not going to risk it. I really don't feel the desire or need to use them on those horns whereas on the 620G, I think they made a significant difference maintaining core at higher volume even on notes not played through the valves.