[gagamut]

recently i upgrade my amp,the amp just have balance input,and i use rca to bal adapter to connect,now i have problem,the midrange much distortion but no hum and no noise,any suggestion to solve the problem??can use this onehttp://www.lundahl.se/sidor/problem_solvers.html,or my amp have problem??thanks

Sam

[Austin08]

I know Cardas and BAT make the rca to XLR connector. I used to use one of those on my system long time ago and had no problem.

[toddbagwell]

if you are using the LL156X XLR units: [from the bottom of the page] they should work.

my guess is that you have one of the attenuator units which is cutting the signal somewhat, but a balanced signal can be double an unbalanced, and it sounds like the input might be getting clipped...

todd

I've also used the cardas XLR units from music direct with no issues other than the cost. I've also used some from parts express...

http://www.musicdirect.com/p-6885-cardas-frca-to-mxlr-adapter-pr.aspx [be sure to get the right ends for your setup] there are a few pairings of male and female.

and

http://www.parts-express.com/pe/showdetl.cfm?partnumber=240-438


ps - I didn't compare directly, but never noticed a difference.

[gagamut]

Hi,

thanks for help,i got the answer,the pre amp designer and power amp maker tell me the following;

'the power amp have to be driven by a real balanced signal, otherwise the amps cannot work correctly. You need a real balanced Preamp'

'If the amp is fully balanced and does not provide a RCA input or gorund one input phase, you are probably driving only one phase of the amp.

 Some amps allow grounding one phase input since it is a differential input circuit. Check with the amp maker to see if it can be done and which pin to ground.'

'Choices are put a converter in-line (either a transformer or an active unit), use a different preamp or change the amp. It looks like they are fully balanced and require a balanced signal, not trying to gound one phase. How well a converter works will vary with the quality of the converter'

[silver_strings]

Interesting most active monitors have balanced inputs but with an adaptor you can connect an rca connection with no problems.