u/hieronymous997

Spent a bit of time researching options and knew I wanted and integrated solution. This unit had decent reviews on Amazon and with what sounded like authentic install experiences. What I liked about this unit is that it has digital output which is sent to the Mark Levinson Amp, and this affects the installation strategy as you use the ML Amp fader, and the sound is shaped by the ML Amp eq, gain and speed control settings. After a lot of tweaking and a professional install I am happy with the results. The look and feel is OEM and while I don’t love the Android OS the CarPlay is very usable and the sound quality is better than any aux or FM modulated Bluetooth adapter that I tried prior to the install. If anyone is interested I can share the settings that I came up with to yield decent audio quality.

I bought an “NOS” Valjoux 72 movement that looked clean and perhaps a little dry, running 18,000 vph +7 seconds and amplitude of 240 with no beat error as received.

When I installed it, I found it was losing 5 seconds every 30 seconds consistent with a drivetrain expecting a 21,000 impulse from the balance wheel.

I checked the fourth wheel and found it had 72 teeth (and one bad tooth incidentally, SEE VIDEO) and realized this “NOS”Valjoux 72 was probably concocted from leftover parts. And some bridges were sanded to remove brand markings rather than being a new ebauche.

The balance wheel is clearly a Valjoux 72 18,000 balance wheel.

Somehow someone has been able to mate this with an escapement, pallet fork and fourth wheel that are expecting a 21,000 impulse.

Question is, should I just replace the fourth wheel to a 60 tooth version, with compatible 6 pinion escapement and matched pallet fork from a standard Valjoux 72, or should I use the opportunity to drop in a Valjoux 726 balance to take advantage of the improved stability and shock absorbance of the 726, since the conversion has already been partially accomplished (and seemingly successful)?

Is there some issue with the 726 balance fitting into the 72 slot, apart from the drivetrain beyond it?