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Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 3:17 am
by nateaff
It's pretty widely accepted that stock rotors for 42s and 50s are too tight and too stuffy and it's common to mod them out with new valves, new valve sections, or people just playing Bach-inspired models by other makers with better rotors on them.

But are there any of you out there who actually prefer your big Bachs with the small valves? Surely there must be a reason they haven't been updated after all these years.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 5:43 am
by tromboneVan
A reliable source, ie, the tech who built I think what was a rotax valve section for a member of the Cl. Orch., told me one of the guys thought it played too open, so they sold it, and are going back to a traditional 42b valve. So apparently, yes, that is sometimes the case.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 6:07 am
by harrisonreed
I have a friend who thinks that but I think he is crazy. 😆

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 6:16 am
by Arendsdale
I replaced the stock rotor on my 42b with an Instrument Innovations rotor, and the difference is night and day. I think that sums up my thoughts on the stock rotors lol

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 8:45 am
by Burgerbob
Sometimes those stock setups are exactly right. I've played the former horn of a notable principal trombonist, a 42BG, and it is perfect as is. Even, great sound, no reason to change the valve. I have owned a few that were acceptable as well, I am playing one in my profile picture. 42BO can be this way as well.

50s I am less convinced are ever actually good with the original rotors.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 9:30 am
by tbonesullivan
The Bach Rotor design has not changed much in decades, and there were generations of players who made them work just fine. I know some people that still have and love their 42Bs with the original valves. All depends on the player and that specific horn.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 10:27 am
by MrKirk
Depends on the model, the Artisan line with the "improved" rotors which many have alluded to are actually the CL rotors from the conn line, are really good. But it comes down to each individual horn and if the rotor is aligned properly.

My LT42BOFG, the rotor was great for response but gave a stuffy feeling especially if you push the air. If you sat back and slowed the air down and let the horn do the work, it was a great playing setup. Unfortunately for me, I want to be able to push air especially for high register.

All that being said, it comes down to what you want as a player and what instrument setup you end up with. If you purchase a modular line such as the Artisan from Bach you can literally swap out entire valve/rotor sections based on what you want.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 10:52 am
by RJMason
Some people make the resistance work and sometimes it helps to have something pushing back. Can find a balance in the middle. All open all the time isn’t always the answer. And obviously when you go down to medium bore a Bach rotor is great on a 36. Would never change the valve on mine unless it completely wears out.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 11:06 am
by Burgerbob
MrKirk wrote: Wed Mar 26, 2025 10:27 am Depends on the model, the Artisan line with the "improved" rotors which many have alluded to are actually the CL rotors from the conn line, are really good. But it comes down to each individual horn and if the rotor is aligned properly.

My LT42BOFG, the rotor was great for response but gave a stuffy feeling especially if you push the air. If you sat back and slowed the air down and let the horn do the work, it was a great playing setup. Unfortunately for me, I want to be able to push air especially for high register.

All that being said, it comes down to what you want as a player and what instrument setup you end up with. If you purchase a modular line such as the Artisan from Bach you can literally swap out entire valve/rotor sections based on what you want.
These are not the stock rotors we speak of

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 11:35 am
by harrisonreed
MrKirk wrote: Wed Mar 26, 2025 10:27 am Depends on the model, the Artisan line with the "improved" rotors which many have alluded to are actually the CL rotors from the conn line, are really good. But it comes down to each individual horn and if the rotor is aligned properly.

My LT42BOFG, the rotor was great for response but gave a stuffy feeling especially if you push the air. If you sat back and slowed the air down and let the horn do the work, it was a great playing setup. Unfortunately for me, I want to be able to push air especially for high register.

All that being said, it comes down to what you want as a player and what instrument setup you end up with. If you purchase a modular line such as the Artisan from Bach you can literally swap out entire valve/rotor sections based on what you want.
Wait, there's a stock Bach with a CL valve on it? This I've gotta see!

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 4:17 pm
by NotSkilledHere
i know the centennial 42BOF models have in particular received some praise before but those i thought were meinlschmidt valves.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 4:34 pm
by TomInME
The stock rotors on the 50 can be made to work, but it's a LOT of work. Why bother? Nostalgia?

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 5:06 pm
by Pezza
I have no issues with standard Bach 50 rotors. Probably because I started on 1, and have played many others since, they just feel normal!

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 7:06 pm
by jjenkins
I prefer stock rotors on the 42 and 50. I make sure the ports are aligned and the instrument has been ultrasonically cleaned, and then I use a mouthpiece which I feels works with the resistance of the horn for balance depending on the sound I have in my head and how I use my air. For Leadpipes, I only use stock or MV copies. Anytime in the past when I've tried to use a Shires or Edward leadpipes... or any pipe not expressly designed for a Bach, all of the character in the sound was lost.

I've modified many Bach 42s and 50s in the past, with Hagmanns, Rotax, Olson rotors, Thayer, and a first-generation Shires valve set. I'm perfectly content with a standard Bach valve, but I will admit that the Rotax is a tremendous improvement while retaining the character of the original. I feel the biggest issue for the 42B isn't the valve, but the undersized neckpipe‼️ (thanks to Vincent Bach's stubborn frugality).

Now, the linkage on the Bach miniball is an issue for a separate conversation.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 7:41 pm
by nateaff
jjenkins wrote: Wed Mar 26, 2025 7:06 pm
Now, the linkage on the Bach miniball is an issue for a separate conversation.
Hey they're better than the old ball and cage linkages that sounded like cycling a shotgun :idk:

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 7:46 pm
by jjenkins
Truthfully, both can work when maintained regularly with the correct lubricants.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 8:20 pm
by Blabberbucket
harrisonreed wrote: Wed Mar 26, 2025 11:35 am
MrKirk wrote: Wed Mar 26, 2025 10:27 am Depends on the model, the Artisan line with the "improved" rotors which many have alluded to are actually the CL rotors from the conn line, are really good. But it comes down to each individual horn and if the rotor is aligned properly.
Wait, there's a stock Bach with a CL valve on it? This I've gotta see!
They are not using the CL valve on Bach horns that I am aware of. I believe the Artisan line is using a Conn Gen 2 rotor with modified knuckles for the X wrap. Peter Steiner stopped by our shop a while back to play our prototype trombones and I am fairly certain that is what he said.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 8:38 pm
by dukesboneman
I`m incredibly happy the way my 50B3 plays top to bottom

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 8:59 pm
by jjenkins
Blabberbucket wrote: Wed Mar 26, 2025 8:20 pm They are not using the CL valve on Bach horns that I am aware of. I believe the Artisan line is using a Conn Gen 2 rotor with modified knuckles for the X wrap. Peter Steiner stopped by our shop a while back to play our prototype trombones and I am fairly certain that is what he said.
100% correct. This was discussed on this forum years ago when that model was being released.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 9:29 pm
by harrisonreed
I suspected as much

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Mar 26, 2025 10:36 pm
by MBurner
I really like them on the Bach 42’s that I play regularly. My daily driver has been rebuilt and aligned properly. The valve is excellent. I like the resistance in the lower register, and the high register is immaculate. The ball and cage linkage is like driving a mechanics pet of a car- once you know how to lube it, it works perfectly and quietly.
My work horn is a stock 42CG that’s silver plated. It has the older ball and cage linkage, and it has the traditional wrap on it. I’ve never had a problem playing any part, even faking bass when needed.
I grew up playing a Yamaha 448, so maybe I’m just used to rotors, and as I studied with teachers that played old Bach 42’s, maybe I associated Bach as a “make it work” situation for the sound you can get from the horn. I’ve tried almost every other valve out there (missing you, Miller Valve), and haven’t found something that worked as well for all playing that I do.
I have a Bach 50 that I had rebuilt with Instrument innovations valves. Completely different horn. More open, compression is less of a factor. As I’m not a primary bass player, I can’t say much, but they play nice. Just different, neither good nor bad.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Thu Mar 27, 2025 7:41 am
by tbonesullivan
jjenkins wrote: Wed Mar 26, 2025 8:59 pm
Blabberbucket wrote: Wed Mar 26, 2025 8:20 pm They are not using the CL valve on Bach horns that I am aware of. I believe the Artisan line is using a Conn Gen 2 rotor with modified knuckles for the X wrap. Peter Steiner stopped by our shop a while back to play our prototype trombones and I am fairly certain that is what he said.
100% correct. This was discussed on this forum years ago when that model was being released.
I would assume that the valve on the "regular" Artisan A42 and A47 horns with the rotary valve are also the same valve, as they definitely have nickel silver casings, which the stock Bach rotors do not.

I have a Bach 42BOF with the Meinlschmidt Open Flow valve, which I like very much, though one thing I have always wondered is whether the gooseneck is the same ol undersized gooseneck from the Bach 36 that the Bach 42B and 42BO use.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Thu Mar 27, 2025 8:14 am
by elmsandr
I have an ancient Single Bach 50 with a great rotor. Huge fat sound all the way down, doesn’t back up, and essentially maintenance free.

That said, every other Bach rotor I’ve interfaced with (about a dozen by now) has left me wanting.

Cheers,
Andy

Re: Does anyone actually prefer stock Bach rotors?

Posted: Thu Mar 27, 2025 8:36 am
by Arendsdale
jjenkins wrote: Wed Mar 26, 2025 7:06 pm I've modified many Bach 42s and 50s in the past, with Hagmanns, Rotax, Olson rotors, Thayer, and a first-generation Shires valve set. I'm perfectly content with a standard Bach valve, but I will admit that the Rotax is a tremendous improvement while retaining the character of the original. I feel the biggest issue for the 42B isn't the valve, but the undersized neckpipe‼️ (thanks to Vincent Bach's stubborn frugality).

Now, the linkage on the Bach miniball is an issue for a separate conversation.
When I had my stock rotor swapped with an Olsen valve, we also swapped the gooseneck. We also switched the linkage for the Olsen version

Re: Does anyone actually prefer stock Bach rotors?

Posted: Thu Mar 27, 2025 10:19 am
by jacobgarchik
I've been playing the same Bach 42b for 35 years. The only thing I had done was convert to screw bell.
Sometimes I read stuff here and then think about getting a different valve and then think about the meme with Batman slapping Robin.
Wasn't Rejano playing one of these until recently? and, like, every orchestra player in 1980?

Re: Does anyone actually prefer stock Bach rotors?

Posted: Thu Mar 27, 2025 2:13 pm
by Arendsdale
jacobgarchik wrote: Thu Mar 27, 2025 10:19 am I've been playing the same Bach 42b for 35 years. The only thing I had done was convert to screw bell.
Sometimes I read stuff here and then think about getting a different valve and then think about the meme with Batman slapping Robin.
Wasn't Rejano playing one of these until recently? and, like, every orchestra player in 1980?
How does the screw bell feel when playing on the 42? Does it change the sound much?

Re: Does anyone actually prefer stock Bach rotors?

Posted: Thu Mar 27, 2025 3:47 pm
by Posaunus
jacobgarchik wrote: Thu Mar 27, 2025 10:19 am I've been playing the same Bach 42b for 35 years. ...
Wasn't Rejano playing one of these until recently? and, like, every orchestra player in 1980?
"until recently" - Why do you think David Rejano changed?
Sound? Intonation? Maintainability? More cooperative manufacturer? Endorsement benefits? Shiny new thing? Better slide (action/smoothness)? Better valve (action/restriction/stuffiness)? :idk:

Why is the Bach 42 no longer the dominant orchestral trombone?
New valve options? Manufacturing quality? Keeping up with trends? Social media? ... :idk:

Re: Does anyone actually prefer stock Bach rotors?

Posted: Fri Mar 28, 2025 8:01 am
by jacobgarchik
Posaunus wrote: Thu Mar 27, 2025 3:47 pm Endorsement benefits?
nobody ever got a big pr blitz from staying with the same old horn...or from switching to a vintage horn.

I like new stuff, and innovation, and manufacturers experimenting with stuff...but sometimes I wonder if trombones cost as much as bassoons or violas whether people would be switching as often as they do.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Fri Mar 28, 2025 8:03 am
by jacobgarchik
Arendsdale wrote: Thu Mar 27, 2025 2:13 pm
jacobgarchik wrote: Thu Mar 27, 2025 10:19 am I've been playing the same Bach 42b for 35 years. The only thing I had done was convert to screw bell.
Sometimes I read stuff here and then think about getting a different valve and then think about the meme with Batman slapping Robin.
Wasn't Rejano playing one of these until recently? and, like, every orchestra player in 1980?
How does the screw bell feel when playing on the 42? Does it change the sound much?
It plays very well. It's more front heavy and I often use a neotech strap as a result.
That horn sounds great. I've used it for dozens of projects and recordings, before and after screw bell.
Stock early 80s 42b that my parents bought me in 1990 for $600.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Fri Mar 28, 2025 9:53 am
by Kbiggs
Sometimes horns just work out of the box. Sometimes they don’t.

I bought an early 80’s 42C when I first worked in a music store. Great horn out of the box. Later, I changed the valve to an original OE Thayer valve because… well, everyone else was. This was in the days when people thought you needed bigger, more open, and heavier equipment to get a big, fat, wide sound (whatever those adjectives mean).

As I’ve grown older, and with adult-onset asthma and other health problems, I’ve needed a more efficient instrument. It now has an Instrument Innovations rotor, and I’m using a stock Bach leadpipe. I can still get a big, fat, round sound, just more efficiently.

******

There’s an anecdote that I saw a few years ago here on TC (or maybe the old forum). A fellow gets called to play as a sub with an orchestra. He pulls out his old 42B (or Conn 88H), plays the concerts, gets good reviews from the brass section, pleases the conductor. One of the other people in the trombone section says, “He played well for a guy with an old horn.”

The moral to the story: Listen with your ears, not your eyes.

Who cares if you play with the latest valve, an open wrap, or a red bell with a sterling silver [insert artist name] leadpipe? It’s the player, not the horn.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Fri Mar 28, 2025 11:57 am
by Danitrb
I played for over 10 years on 42 closed wrap, little bit stuffy for sure, not just trigger notes but also rest of horn, even when you don't use valve. Now I play on 42 standard rotor open wrap, and I find is very balanced. Like other members said it depends on the player, the instrument (your equipment) and your style of playing.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Sat Mar 29, 2025 3:49 am
by MrHCinDE
I’ve never liked any 42 with standard rotors, neither on the Bb nor F side of the horn.

For bass, I really like the sound of a 50, even more so in gold brass, but simply cannot justify the price of my money-no-object setup for my 3rd instrument (behind tenor and euphonium). For that reason I’m pleased it is still possible to find a Bach 50 with two standard rotors for a reasonable price.

The low C and B are perfectly solid for me on my setup. If I try to play FFF in the lower register it does back up a bit compared to some horns I’ve tried. This is only ever noticeable in my practice room and I presently have no need for FFF pedals in any musical context.

If I play more bass in the future, and also develop the air to support it, I could get the valves swapped out, for now it’s just fine.

Based on price/performance I would say I prefer my standard rotor 50 it to the fancier options.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Sat Mar 29, 2025 9:02 am
by MrKirk



Wait, there's a stock Bach with a CL valve on it? This I've gotta see!


:biggrin:

Re: Does anyone actually prefer stock Bach rotors?

Posted: Sat Mar 29, 2025 12:52 pm
by jthomas105
I have a mid 70's corporation 42B. mid 80's I had Eric Swanson modify with a Minnick style open wrap and removed the lead pipe to make interchangeable. All of that made huge differences.
Then 8 years ago I got the open gooseneck replacement part and at the same time reversed the small side of the tuning slide crook to be like a 88h.

That made a huge difference and open everything up.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Sat Mar 29, 2025 2:43 pm
by harrisonreed
MrKirk wrote: Sat Mar 29, 2025 9:02 am



Wait, there's a stock Bach with a CL valve on it? This I've gotta see!


:biggrin:
Apparently one actually existed, but it was not a stock horn:

https://reverb.com/item/83037230-bach-4 ... 2000-rotor

Re: Does anyone actually prefer stock Bach rotors?

Posted: Sat Mar 29, 2025 5:14 pm
by UATrombone
harrisonreed wrote: Sat Mar 29, 2025 2:43 pm Apparently one actually existed, but it was not a stock horn:
https://reverb.com/item/83037230-bach-4 ... 2000-rotor
Hm... Never seen this style of valve cap before.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Sat Mar 29, 2025 7:14 pm
by elmsandr
I mean, I have one, too… but also not factory.

Worse, mine mates with a Mt Vernon.
Andy

Re: Does anyone actually prefer stock Bach rotors?

Posted: Sat Mar 29, 2025 9:38 pm
by MrKirk
harrisonreed wrote: Sat Mar 29, 2025 2:43 pm
MrKirk wrote: Sat Mar 29, 2025 9:02 am



:biggrin:
Apparently one actually existed, but it was not a stock horn:

https://reverb.com/item/83037230-bach-4 ... 2000-rotor
haha hey i bet that horn played or plays well.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Sun Mar 30, 2025 3:49 am
by LIBrassCo
The question might as well be who likes backpressure? It's just a different way to play. I used to like something to push against, but the more I played, and the stronger things got, the more I just wanted the horn to get out of my way. It wasn't so much out of choice as it became a necessity to get the instrument to consistently do what I want.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Apr 02, 2025 3:07 pm
by MrKirk
LIBrassCo wrote: Sun Mar 30, 2025 3:49 am The question might as well be who likes backpressure? It's just a different way to play. I used to like something to push against, but the more I played, and the stronger things got, the more I just wanted the horn to get out of my way. It wasn't so much out of choice as it became a necessity to get the instrument to consistently do what I want.
I agree with what your saying, resistance makes things easier. That being said, I absolutely loved the open feeling of my axial flow as well as the consistency of tone. But the valve simply has a high latency which is why I opted for either hagmann or a balanced rotor. Every player will have different preferences, and that's the beauty of having so many configurations and manufacturers. Much in the same way euphoniums are today, but 30-40 years ago... it was either yamaha or besson. What a time to be a musician!

Re: Does anyone actually prefer stock Bach rotors?

Posted: Wed Apr 02, 2025 4:35 pm
by jjenkins
I'm not sure if resistance makes everything easier. Logically, less resistance would make things easier. I think it's all about balance, as I mentioned earlier. It's about having the right amount of resistance, the balance between your horn and mouthpiece. Too little resistance and you get an uninteresting sound; too much resistance and you perhaps get a sound with more character, but it constantly fights you.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Thu Apr 03, 2025 1:40 am
by boneAngo
I think if you are playing good enough, the resistance or the design won't affect u doing any technique on your trombone. It's just whether the design fits your sound concept. It's totally your own preference. I personally think that sometimes if you try to appreciate that stuffy sound you will find something in it (define it an artistic value). To be simple, just find good things in so called bad things.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Sat Apr 05, 2025 12:36 am
by LIBrassCo
jjenkins wrote: Wed Apr 02, 2025 4:35 pm I'm not sure if resistance makes everything easier. Logically, less resistance would make things easier. I think it's all about balance, as I mentioned earlier. It's about having the right amount of resistance, the balance between your horn and mouthpiece. Too little resistance and you get an uninteresting sound; too much resistance and you perhaps get a sound with more character, but it constantly fights you.

Depends on the player. There's no "right" amount of resistance, this is whole thing is far too subjective for that to ever be true. More like right level of resistance for you. Also, there is zero relationship between resistance and quality of sound. Zero. I work with phenomenal players with anything from stock rotors to the most open Thayer horns. Every one of them has a great sound that is uniquely their own in some way.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Sat Apr 05, 2025 3:09 am
by jjenkins
I assumed most would understand I meant for it to be personalized, i.e., the right amount of resistance... 'for that person.' And then they'd find a mouthpiece that works with that horn.

For example, Aiden (aka burgerbob) did a video demo on his bases and he was asked why he didn't use one mouthpiece for the sake of there being one constant in comparison. And he correctly responded that each horn responds better to different mouthpieces. (paraphrase)

And I disagree that there's no relation between resistance and quality or character of sound. So you're saying if you take two identical Bach 42s (or any two identical horns for that matter) and install an axial on one and a traditional Bach rotor on the other, the two will sound and respond exactly the same with the same player? Of course a good player will sound unique in their own way, but will they sound identical? Forget valves, even leadpipes make a difference. And dual radius tuning slides, etc. I realize you're a designer/builder and respect your specified knowledge. I'm not trying to "school" you, for the record. I just don't understand your argument.

Most things, if not everything, makes a difference, either to the player or to the audience.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Sat Apr 05, 2025 6:50 am
by LIBrassCo
jjenkins wrote: Sat Apr 05, 2025 3:09 am I assumed most would understand I meant for it to be personalized, i.e., the right amount of resistance... 'for that person.' And then they'd find a mouthpiece that works with that horn.

For example, Aiden (aka burgerbob) did a video demo on his bases and he was asked why he didn't use one mouthpiece for the sake of there being one constant in comparison. And he correctly responded that each horn responds better to different mouthpieces. (paraphrase)

And I disagree that there's no relation between resistance and quality or character of sound. So you're saying if you take two identical Bach 42s (or any two identical horns for that matter) and install an axial on one and a traditional Bach rotor on the other, the two will sound and respond exactly the same with the same player? Of course a good player will sound unique in their own way, but will they sound identical? Forget valves, even leadpipes make a difference. And dual radius tuning slides, etc. I realize you're a designer/builder and respect your specified knowledge. I'm not trying to "school" you, for the record. I just don't understand your argument.

Most things, if not everything, makes a difference, either to the player or to the audience.
Nothing sounds identical, which is why I didn't say that. I am saying any setup can make a phenomenal sound. Whether it's your cup of tea or not is another matter entirely. Don't get me started on the right mouthpiece for a specific horn bs, that's a totally different rabbit hole. Lol.

Re: Does anyone actually prefer stock Bach rotors?

Posted: Sat Apr 05, 2025 7:40 am
by tromboneVan
Seems to me the biggest determinator of how a horn "blows" is the mouthpiece, leadpipe combination, and then the valve is secondary. I think now that I have the former dialed in, I can play different valves, and make a slight adjustment and fine tune the horn. I can't speak for the stock rotors on Bachs, or how similar or not the stock valves are on my Benges, but after trying nearly every valve out there, I find counter-intuitively perhaps, that the resistance provided by the more tight valves gives me something to blow against in the low register, and that resistance (comparing to Thayers, or some thing more "open") is my preference sound and playing wise.