unbalanced to balanced

[DAX616]

Can an amplifier or preamp with unbalanced in/out be modified to balanced in/out? I realize surgery may be required.

[dragonfyr]

The amplifier itself cannot be easily modified, but there are several ways to modify the resultant I/O connections (albeit without the benefit of a totally balanced topology).

http://www.jensen-transformers.com/faqs.html#faq4

http://www.roscorrentals.com/equipment_specifications/Tascam%20LA-81.pdf

http://www.sonifex.co.uk/redbox/rbbl2_ld.shtml

http://www.gainesaudio.com/200.htm

http://beradio.com/features/radio_round_cord_square/

I have a circuit diagram for converting the cables around here someplace - I will try to find and post it.

Personally, I wish more (non-pro) amplifier manufacturers would move to a balanced topology!

[DAX616]

THANKS FOR THE INFO!!!!

[DrWho]

http://www.colomar.com/Shavano/cable_xlr_to_phone.html

Depending on your situation, you can either just use a special cable, or you will need to use a transformer to match the impedances. Though I'm sure there is a more scientific approach, I just default to using a cable adapter first and if the gain structure is off, then I'll put in a device with the transistor. You can get the balanced to unbalanced transistor adapters at radioshack, but they're $25 each. I bought my cables at a local pro audio store for a grand total of $5.

When you do the cable adapter route you lose the noise reduction from the balanced line, but in a home setting where the lengths are short this shouldn't be an issue (versus a PA setting where the lengths can be hundreds of feet).