needed idiots guide to powering with batteries

[looboo]

thanks , what value fuse do need?

 

[Rundmaus]

Ideally,

the first available value above your expected load current.

Rundmaus

 

[looboo]

Hi thanks Rundmaus, but after rereading Gootee ' instructions for adding caps I think I am going to abandon the idea (don't want to destroy a brand new preamp) and move on ,I did not realise that simply replacing an external plug top 18v dc supply with batteries would be so complex.
thanks to everybody for the education

 

[Rundmaus]

It is not that complex.

If it was powered from a simple wall-wart before, you can just connect the batteries via a reasonable dimensioned fuse instead. A simple wall-wart probably has significant ripple and noise on its DC output, so the SLA batteries will do better than that without any decoupling caps.

Just try it. If it isn't better, go back to the manufacturers supply. I wouldn't fiddle with the preamp circuit itself without sufficient knowledge, there I agree with you.

Rundmaus

EDIT: No offence meant, but people tend to drown things in perfection here, sometimes. If a preamp has a bad supply, a better supply will be an improvement. And a first step.

 

[looboo]

Hi, I did try it before asking then thought I better check that it was safe to do so, the existing supply is a plastic universal voltage thing with a set of slot on plugs for use in different countries its tiny and cheap looking so don't think it is the preamps strong point, batteries seemed to open up the sound and remove some mushiness,
so you think with a fuse in line with the 18v output I should be ok.
thanks again

 

[Rundmaus]

For a beginning, this should be ok, yes.

Just make sure there is a fuse. And be careful when wiring the SLA batteries in series. Make sure there is no possibility of shorts before the fuse. This has the potential for *real* fireworks, as said before.

Rundmaus

 

[looboo]

Thanks Rundmaus I think I will try it again as I said the improvement was noticeable.
regards looboo

 

[gootee]

Sorry. I didn't read the beginning of the thread. I assumed that you were DIY'ing the preamp. By all means, use batteries directly in place of a wall-wart-type of power supply. They are almost guaranteed to be better, especially if you don't use six feet of wire to connect them.

If you ever get the time, and have a suitable electrolytic cap lying around, try connecting it across the battery terminals, or where the battery connects, and see if you can hear a difference.