Battery power experiment

lbr said:
- I'm unsure about the effect on dynamics at the moment and need to listen further. I think this will have to be done on vinyl as there is an obvious effect on the speed of the CD player when switching between mains and battery power which makes direct comparison very difficult. My CD player is specified for a 230V input, which matches the inverter output. My mains is generally in the 248-251V range. It's not something I'd specifically noted before, but listening to the two power sources back to back it is obvious that the CD player runs fast on mains power.
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Should that post have been dated April 1st?
 
Markus S said:
Should that post have been dated April 1st?
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I don't recall the precise date of posting, but I am quite sure that it was not in this month, so I have no reason to doubt the accuracy of the recorded time stamp.

have a gander at this

Voltage does apparently affect CD replay speed. I know this is true as it is written thus on Russ Andrews' website:

The mains voltage has a surprising effect on the performance of a CD player. The motor speed is voltage controlled not frequency controlled with a crystal reference as most people would expect.

Even though the motor supply voltage is regulated, the mains voltage does affect it, making it play slightly faster or slower.

The effect on the music is quite large, making it sound either fast and exciting or slow and relaxed. I discovered this whilst experimenting to find out why a 'Pandora' isolating transformer, that was claimed to improve CD sound quality, did affect the sound. I discovered that the 'Pandora' was simply increasing the mains voltage by 24 volts, hence increasing the play speed and making the sound appear more 'exciting'.
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The speed with which the CD spins changes as it plays, from 495rpm in the centre down to 212rpm at the edge.

Mr Andrews seems to suggest that even though the voltage is regulated, it's not really regulated?
 
He does seem to suggest that doesn't he. I'm glad there are clever folk like him around to do my thinking for me. Now pass me a grape.
 
The RA quote is abject rot.

CD spindle speed is servo-controlled, and the data fed into a small FIFO buffer. From that it is clocked-out. NO link between mains voltage and CD player 'speed'.



Pssst, wanna buy a bridge...?
 
I'll second the no link between speed of disc and voltage ...

but don't dismiss the effect of lower voltage [brown out] on the final sound .....having experieced it does effect the sound

Conversly I would not be at all surprised that 250 volt ac is likely to effct the final sound as well ...but not for the reasons originally speculated ......

just suppose that the internals of a cd work at 25v dc but the tranny is supplied with 250 v 20 volts higher near 10% ...this extra enery is normally dissipated as heat ...this may make the cdp run too hot ....we all know how heat effects resistance ?

I don't think it unreasonable to assume that whats being heard is being miss recognised as speed stability
 
Maybe, maybe. I don't share your knowledge of or enthusiasm for the inner workings of CD players. I'm half inclined to time a CD with a stopwatch once on the mains and once on the battery. Unfortunately, only half inclined.

What kind of bridge - I may be interested as I have a troublesome span it could suit nicely.
 
I might try running my system through a "resonating polarizing regulator"


...sorry thats Star Trek. :p
 
Batteries deteriorate over time, chances are you won't notice the subtle change, but at what point will mains beat it again? (assuming the change is better - big assumption from what a very techy person was telling me, and no, I cannot recall/understand his reasons for rebuffing using batteries)
 

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