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Why not batteries instead of power supplies?

I read about issues with power supplies, like noise from AC outlets, ripples in voltage etc.

Why not just use a large battery that can be recharged? If batteries can power cars, they can for sure power amplifiers.
defiantboomerang
guidocorona
4,114 posts
 

The new Rowland Power Storage Unit (PSU) is a full chassy external ultra-capacitor-based power supply. It has been designed to power simultaneously up to three line-level devices... A Rowland Aeris DAC, a Corus linestage, and as one spare output for future use.


I have had it in my system for about three months, and have applied it to my Aeris, as I am not currently using a line stage. The enhancement that PSU has brought to the system is rather phenomenal, for all audible parameters I can think of.... Its effect is tranformational: more in line with a substantive upgrade of all electronics, rather than the replacement of just one power supply.


Regards, Guido




kosst_amojan
2,095 posts
 
@larryi 
The ones Mouser is selling are designed for UPS backup power supplies. The main thrust of development for supercaps is to use them are replacements for batteries. A lot of gear already uses small supercaps for memory retention and running clocks in DVD players and the like. They replace button cells. I've never tried anything with supercaps in an amp. I'm not sure my amp building skills are to that point yet. I'd want to try it on a pre-amp first. Make a board and just hang up a half dozen or so of the little 2.7V 100 Farad deals and see how that works. Those are cheap. 
hglaser
7 posts
 
As a cheap experiment born of curiosity, I tried using a a widely available commercial "online" uninterruptible UPS, which does a full AC>DC>AC conversion for all power output, here:    https://www.amazon.com/dp/B0050NZTQ2/ref=cm_sw_r_sms_tai_GYJ4zb8PJA3P1. In other words, it is NOT a stand-by power source; it is the primary source.  It has a rated output of 1500 amps, far in excess of my system's needs.  According to the included monitoring software, output, voltage and frquency were rock steady regardless of the music. 

The results were impressive, even though the nominal THD quoted for the UPS was poor.  Using a sound meter, hiss and noise at the speakers dropped 4-5 dB. Music sounded both more detailed and with greater air. Bass seems unchanged, but admittedly I am not a bass fiend. Ymmv. 

Cheers, Alex
georgehifi's avatar
georgehifi
4,966 posts
 
Jeff Rowland Design Group offer battery powered amplification since early 90's
When things were linear and Class-A/B then this could have helped reduce noise ect, but with their new class-D stuff today, batteries can't solve the biggest problem they have, which is the Class-D switching noise filtering.

Cheers George
zavato's avatar
zavato
903 posts
 
IIRC, ASR makes battery powered gear
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