Line Level or what?

[Rick6]

Hi,

 

Any help with the following newbie query will be much appreciated.

 

I just took the plunge and bought my first PA. I got the Yamaha Stagepas 300 (yes, I understand it's near the bottom of the PA spectrum). The pros are size, weight and cost.

 

The application is playing guitar in stereo. I use a Boss ME50 to create a stereo signal (using Stereo Chorus 2). Up to now I've been feeding the L and R jacks into two separate guitar amps.

 

The ME50 has "line/phones" stereo 1/4" output which the manual suggests can be connected to a mixer.

 

My idea was to feed that output into the stereo line in RCA jacks on the Stagepas.

 

The Stagepas has two stereo channels.

 

I figured I'd plug the Left ME50 output into the left input of Channel 5/6. Then I'd plut the Right ME50 output into the Right input of Channel 7/8. That way, I'd be able to use the individual channel gain controls to control the relative volume of the two speakers. The idea is to maximize stereo separation at my own ears while I'm playing.

 

I got a cable that goes stereo 1/4" to mono RCA jacks.

 

So, I plug it all in, and here's what happens.

 

The overall volume is ridiculously low.

 

In troubleshooting it, I discover that there isn't much difference between the volume of the ME50 line/phones output and the volume of the usual L and R outputs. The difference is audible, but certainly not dramatic.

 

The ME50 spec sheet doesn't say what the output level of the line/phone jack is. It does mention -10dbu as "nominal output level", apparently for the L and R jacks.

 

The spec sheet doesn't seem to mention it, but I found an online review which mentioned "a 30db pad" on the line in jacks of the Stagepas. If I understand this, I've got a signficant automatic reduction in the amount of signal allowed thru, and I can't adjust it. No?

 

The Stagepas spec sheet comes with a block diagram which labels the stereo inputs as -20 to +20 dbu.

 

If I plug the guitar directly into the mono channels and set them on "mic" input, the thing is really loud. But, there's no pan feature, so I have to give up the stereo feature to use it that way.

 

If I use the compressor feature of the ME50, I can raise the volume to the point where the system is loud enough, although it doesn't sound quite as good. The compressor introduces a certain harshness and lack of articulation.

 

As a check, I plugged my CD player into the stereo inputs. It's okay, but not particularly loud. I also plugged my headphones into the line/phones of the ME50. By turning up the output level control of the ME50 (compressor off), it drove the headphones pretty well. That same setting won't drive the Stagepas to a loud enough level to play with a drummer.

 

So, if I've diagnosed this correctly, my problem is that "line/phones" on the ME50 simply isn't putting out enough signal for the line inputs of the stereo channels of the Stagepas.

 

And, the problem seems to be that the ME50 output isn't particularly loud, and the Stagepas input isn't particularly sensitive. [that 30db pad?].

 

I imagine there are several solutions, none of which result in quite as simple a system as I'd hoped.

 

Presumably I could insert a preamp between. Maybe not a bad idea, since I could maybe add better equalization at the same time. I have no idea what to buy for this.

 

I could replace the pedal board with one that puts out more signal. I'd been thinking about a GT-8 -- but it's a Boss product also. If the problem is that their definition of "line level" is too low for a Yamaha product, I'd end up with the same difficulty. But, I can't believe that Boss and Yamaha would disagree on this. I must be missing something.

 

I could return the Stagepas and forget the whole thing.

 

Ideas?

 

Rick

[kevinnem]

nominial out put of the me 50 is -10 Dbu.

 

This is what is used for all the "consumer" line level stuff like cd players ect.

 

 

"pro" level stuff uses +4Dbv (Dbv not Dbu right?).

 

Not that +4 is really and more "pro " it is just kinda a converntion that is used to desctibe stuff in the industry.

 

I can't find a manual on the mixer, but it is possible that the mixer is expecting +4, and you are feeding it -10, this would have a nociable differance in level.

 

I assume that you useing the RCA in's as there are no 1/4 inch avalible on the last input.

 

are you running the channel volume *and* the master volume really hi and still not getting anyy volume out of it???

[Rick6]

Thanks, that makes sense.

 

Yes, I can turn the Master output level of the ME50 all the way up, and the guitar output all the way up (RMC electronics in a Godin Multiac Nylon) - and - the channel and master volumes to about 3 o'clock on the Stagepas, and it's still not that loud.

 

The only way I can get it loud is to use the ME50 compressor in the stereo inputs - OR - plug into one of the mono channels set to "mic". With the mono "mic" input, the thing is LOUD.

 

Rick