Author Topic: Buzzing from my F1-X DI Out (Read 280 times)

jazzyvee · « **on:** September 13, 2014, 08:53:00 PM »

I just did a gig tonight and during the first number the stage guy came and changed my DI-out for a mic in front of my speaker cab.
After the gig I had a chat with our sound engineer and he said there is a buzz coming from the DI out on my pre-amp as there was no noise coming from the mic picking up my cab sound.

In actual fact during soundcheck we noticed that there was a distorted crunch coming out of the FOH system when I hit low notes but though it might have been the speakers but it transpires it was not.

Any idea's what needs to be done. For the time being I will swap it with my spare F1-x until I can with your help determine the nature of the problem.

edwin · « **Reply #1 on:** September 14, 2014, 03:06:48 PM »

Cold solder joint?

terryc · « **Reply #2 on:** September 15, 2014, 06:16:06 AM »

Could be a dry solder joint especially on the ground side(centre pin I gather). Did they change the cable or presume it was the socket itself?
Test it yourself by connecting the DI out to another amp and see if it buzzes, unless you already have done that! You will have to use a three pin DIN to 1/4 jack plug cable

jazzyvee · « **Reply #3 on:** September 15, 2014, 06:58:19 AM »

Good point Terry, I haven't done anything yet. I've swapped round the pre-amps and I think I will take the DI out into my mixer record it and listen back through my monitor speakers that way I don't need to mess round with trying to find a DIN to Jack cable.

terryc · « **Reply #4 on:** September 15, 2014, 08:00:52 AM »

Yeah that would do the trick without resolving to a combo cable.
Pity you don't live nearer because I have every combination of cable under the sun(ex PA man you see)
Anyway keep us lot informed

jazzyvee · « **Reply #5 on:** December 19, 2014, 03:08:46 PM »

I used both my F1-X's at a gig last friday and my regular sound engineer was on the desk and said both had good clean signals. So maybe the problem i referred to earlier was something else in the link between di and the mixer. So seems all is well with both my pre-amps. Ive been thinking of putting in new valves as i bought both used and ive had one about 8 years and who knows how long the valves have been in there.

keith_h · « **Reply #6 on:** December 19, 2014, 07:09:07 PM »

Possibly a ground loop if the grounds on your equipment were not on the same electrical legs as the mixer. To get around it you can use an isolation transformer with a ground lift. You can also use the ground lift in the board if it has one.

Keith

sonicus · « **Reply #7 on:** December 19, 2014, 09:06:35 PM »

That just might me right !

terryc · « **Reply #8 on:** December 22, 2014, 03:49:10 AM »

Obviously it was his equipment at fault Jazzy and not yours!

gtrguy · « **Reply #9 on:** December 22, 2014, 11:06:40 AM »

Are you using the Alembic unit?

Sometimes the output jack switching internal contact gets dirty and can cause problems. You open the unit and fold a small bit of very fine sanpaper and pull it through the switch contact points. I gently open them first and then let them close on the sandpaper and pull it through a couple times.

You can see any dirt on the sandpaper, if there is any.