Intonation problem Miraphone 191

[burningchrome]

I only have my slide out an inch or so, but my point is I think it's your horn and not a general design issue. My pedal F is really flat (when low C and middle C are in tune).

Rob

[peterbas]

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[Phil Dawson]

Just as aside - if you have a 5 valve horn and use a 2 whole step slide for the 5th valve you can tune one set of 2/3 combinations to 2/3 and the other set to 5th and all of your 2/3 or 5th combinations will be quite well in tune. I do this on my Miraphone 1293 and it works very well. Phil

[jmerring]

Just a thought. Having played a 191 for a short while, I found yours is not alone. The bore of .835 overwhelmed me, as far as intonation is concerned.

[Roger Lewis]

Have you checked the valve alignment lately. The factory bumpers are unique in that the downstroke bumper is neoprene but the upstroke bumper is cork. These deteriorate rather quickly from the spring tension and the impact. I'd probably start there to make sure the horn is in proper alignment.

Roger

[Dan Schultz]

On a side-note.... Roger Lewis might chime in on this, too....

My 1291 (basically the same horn except pistons instead of rotors) was a bit on the sharp side until Roger suggested I get an 'American' main tuning slide which is a dab longer than the one that came with the horn.

Might not directly fix the Db problem but might allow for readjustment of everything else if you currently have a main slide with 1" long ferrules. The 'American' slide has 2" long ferrules that essentially adds 2" to the main bugle.

[peterbas]

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