ADC moving-iron cartridge has "low" output
I have two identical ADC gold-body XLM-III carts from the late 70s. I purch'd them used, as part of two turntables that were each purchased from different parts of the US. Each cart has a different model of stylus (XLM-III and QLN-2) , and styluses can be interchanged.
The MI series from ADC should output 5.5mV, which I have not measured. However, BOTH these carts are challenged wrt output volume. Not only do I have to crank up the vol. more than 1/3 above other carts, but the sonics are a bit "small" and not "full bodied". It might be due to weakening permanent magnetism -- these are both getting close to 50 yrs old .
The perm. magnet in ADC moving iron series is mounted in the removable stylus, just above the stylus/cantilever assemble.
Not sure what else the low volume may be due to??? These are my my only MI carts in my collection. Anyone know more?
- ...
- 24 posts total
bluz bro adc page https://www.adelcom.net/ADCCart1.html xlm mkIII specs, they say output 6.05 mv https://www.adelcom.net/ADC-xlm%20mk3-Page.html
this chart, top row: 'sensitivity' 0.9mv is different spec than other rows 'signal strength' 5.5mv may be the source of confusion
|
It’s not “different”, it’s just another way of stating output, in this case with respect to stylus velocity. In those days the standard stylus velocity was 3.54 cm/sec. If you multiply that velocity by 0.9, you get around 3.2 mV, which is a bit less than the typical output of an MM and might account for the OP observation. Or it might not. |
Good call on the stiff suspension, as this can be an issue. One of XLM-III stylii had this issue, the other did not. The stiff sus. also leads to DISTORTED sonics. But I was able to mostly restore with a bit of WD40 (see the AK forum for this). About 5.5mV ... I have the orig. box.manual/spec sheet: https://i.postimg.cc/vZ17dbdr/IMG-9864.jpg
|
- 24 posts total