A47 AMP problems

[blawh]

I have received my A47 headphone amp, but i seem to have a few problems. Since the amp doesn't have [ground?] the maker of the amp says that I have to use 2 9vs and use the connecting part of the 9vs as ground. I tested the amps today, and it seems like it works for around 10 seconds, and then I start getting weird noises, and after while there is no noise at all. I have to move the volume to the highest to hear it, and when I hear it it is extremely distorted and unclear... Also, removing the [ground?] and inserting it into either positive or negative seems to give me sound, but after removing the 2 9vs and replugging it in, I have to start over in this process. Please advise!

Thanks.
blawh.

 

[dBel84]

The RA1 uses a different type of virtual ground than the standard cmoy build - essentially pulls off the ground from the junction between the 2 batteries in series - I know there are images out there to visualise this - I suspect that this is what the A47 kit is using; based on these images

If you post images of what you have built and how you connect it, it might clarify things a little.

..dB

 

[Zigis]

This is unsafe way - using battery split as ground. If one battery discharge little faster than other, you can get large DC offset on phones.
You can easy made virtual ground - add TLE2426 rail splitter, or at least two resistors on battery input pins.
Zigis.

 

[angchuck]

you don't seem to make much sense by "Also, removing the [ground?] and inserting it into either positive or negative seems to give me sound, "

A picture will be worth a thousand words.