24V or 15V Power Supply for RA-1 Clone?
May 22, 2004 at 6:50 PM Post #2 of 8

Lil_JV

500+ Head-Fier
Joined
Aug 20, 2003
Posts
816
Likes
10
Can someone please help! I am trying to get this order finished. I know the chip is rated to 18V and there are some tantulum caps before the V+ and V-. Basically I need to know if the amp can run on 24V or if it will fry the chip.

Thanks,

JV.
 
May 22, 2004 at 7:03 PM Post #3 of 8

guzzler

Headphoneus Supremus
Joined
Jan 17, 2003
Posts
1,851
Likes
12
i'd go the 15V for the RA-1, it's really meant for low-Z phones so a high voltage isn't really needed. The 24V supply will, however, probably be more useful in the long run

g
 
May 22, 2004 at 8:42 PM Post #6 of 8

Lil_JV

500+ Head-Fier
Joined
Aug 20, 2003
Posts
816
Likes
10
Ok, hold on. The + of one battery and - of another are supposed to be grounded in the original design. Could I just use a single supply and apply +15V to one side and -15V to the other and just omit the ground? Or do I need a dual supply?

JV.
 
May 22, 2004 at 9:20 PM Post #7 of 8

guzzler

Headphoneus Supremus
Joined
Jan 17, 2003
Posts
1,851
Likes
12
assuming you're using the NJM4556, it's rated 36V, ie +/- 18V, so the 24V supply would be fine. However, the arrangement of the batteries in the RA-1 means the ground is at the junction of the two. Unless you use a dual supply, you'll need to have some way of creating a virtual ground. IMO, you're no longer building an RA-1 clone when you do that, as many attribute some of the tonal characteristic of the RA-1 (just a well calculated CMoy, really) with that arrangement.

JV, a single supply doesn't give it +/-15V, it puts out 30V, the +/- have to be referenced from a ground you then create, and therefore are dependent on it, so you can't "omit" ground as you put it

g
 

Users who are viewing this thread

Top