Fixing RF issues

[mario_farufyno]

Hi folks, I'm an proud owner of a 4 string Alembic Rogue bass from Brazil. I can't properly express myself in English, but I hope you can understand me.  
 
Sometime ago I came here asking for help with an annoing problem. My Alembic was picking up radio signal interference despite having the recomended ferrite bead device in it. To my surprise I saw this was a concern to many (specially with non-US residents).
 
It was a shame having an expensive Bass like this and not being able to use it anywhere. It seems that Brazil doesn't properly control Radio emissions and this is a tremendous problem to Alembic's Pickups in some sites.
 
I was really down when Mica asked me to send the entire harness to Mother Ship because I didn't know what more to do (and knew that shipping - plus taxes in Brazil - would almost cost me a new bass!).
 
That time I met an other Alembic owner and he conveinced me to try a new Cable. Mine was my trusty  15 years old Whirlwind Cable with really bad scratched plugs, so I tried his and... the problem was gone!
 
Man, I solved the problem simply buying a new Cable! THIS is a shame, I never thought that a Cable could be so fundamental.
 
So, if you are experimenting problems with Radio interference, try check your connections first. Verify your Cables and check Amps and Wall Socket's grounding.  
 
I solved 90% of my problems with RF interference keeping my rig sharp. Hope this tip can help more people.

[keurosix]

Holla Mario,
Welcome to the club. I have found that my Alembics are very clean and also very sensitive to any background noise or wiring shortcomings. You can minimize RF noise by certain isolation techniques that most audio technicians know - people who run professional sound system support. Talk to the sound man and the set up crew for any big venue and they can show you a few good tricks. Sometimes a good ground lift to isolate your amp rack will do wonders. A seperate power line for audio away from the lights power source really helps too. Definitely using good shielded cables helps too as you found out. I always carry a cheap line circuit tester to test the electric sockets before pluging in. I know there are other club members with much greater knowledge of this topic than me. Don't give up on the Alembic bass!
Kris

[funkyjazzjunky]

Welcome to the club.  
 
 
 
(Message edited by FunkyJazzJunky on September 23, 2008)

[funkyjazzjunky]

 
 
(Message edited by FunkyJazzJunky on September 23, 2008)

[spliffy]

Mario, the first thing I would do after trying out what Kris suggested would be to buy ferrile beads (or is it ferris beads), sorry I cant remember the exact name.  
Anyway, you run the pickup wires through the bead a couple of times and that may help.
I had the same issue with my Distillate. The beads did not work. I ended up sending the electronics to Alembic for upgrade, and it worked. It cost money and it took several months, but it worked.
Good luck, and keep us posted.
 
Albert

[pacificshine]

The audio cord (especially the type using phone plugs) is critical in achieving a good, clear signal path. I've personally thrown out many bad or questionable cords that exhibited a similar symptom or other noises and replaced them with new and reliable cords. The cost of a good, reliable cord (whatever it may be) is well worth it. Personally, I make all my cords now. I found that using a quad microphone cable works best (I like the Mogami Quad Hi Definition mic cable). I twist the two blue wires together and the two white wires together, solder the white wires to the tip of the plug and ground the two blue wires together with the shield conductor to the ground lug of the plug. I can also customize the length of the cord and it's not too expensive if you get the cable in bulk (on a spool). Use high quality phone plugs and you'll have a reliable instrument cord that will not fail you.

[pacificshine]

In response to a member's comment in another thread:  It's true that cords in working order should not make a noticeable difference in sound quality, but the higher quality cords are likely to better protect you in noisy environments. They are also more rugged and will withstand greater abuse. The Quad Mic cables are designed for a balanced output signal (XLR output) as they tend to cancel noise better than the regular mic cables. I tried it once on a phone plug (unbalanced signal) and really liked it. The two wires connected together to the tip and the other two wires plus the shield jacket connected to the ground terminal on the phone plug make it a really strong and reliable connection. After trying the Mogami cable I just couldn?t go back to any standard, pre made cord. To make it really work use high end phone plugs (I think we use Switchcraft, all metal plugs). The good quality plugs are easy to solder to and the insulation will not melt as you heat up the terminals. I was surprised how easy it was to make these cables with only a few simple tools.

[FC Bass]

There is a difference in sound between my Evidence Audio cable and my Cordial cable (same length and both with Neutrik connectors)
Difference is subtle and probably not noticeable in a bandmix, but it's there. (best noticeable in the highs)

[mario_farufyno]

Hi buddies, thanks for answering. I love my Rogue and will never give it up, Keurosix. The fact is that this problem simply teached me how important can be having the right Cord and using a properly grounded power source.
 
I know the Alembic isn't the source of this problem. Here in Brazil you can find some spots where your TV or Cell Phone picks up illegal radio transmission!
 
Spliffy, thanks for the tip but I have these Beads on my Rogue and they weren't much of a help. The definitive solution was simply using good Cords (although there is one place where I still can't use it - but I know this stage isn't properly grounded).
 
Thanks for the Tip, Pacificshine. Definitively I will try these idea of using Mic cables.

[mario_farufyno]

Maybe some basses are not so sensible with what we're using with it. But it seems Alembic's so hi-fi that demands better companion.
 
Best regards!
 
(Message edited by Mario Farufyno on September 26, 2008)