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 #139467  by Winterland
 Sat May 31, 2014 8:49 pm
Hey people hope all is well,

Wondering what type of chord you use for your MAC amps that run to your speaker. I modified a lamp chord to hook to the MAC. Left side hooked to the 8, the right is on the common. Any suggestions? I am trying
to eliminate a slight buzz when turned up. appreciate any input.
Last edited by Winterland on Sun Jun 01, 2014 11:21 am, edited 1 time in total.
 #139480  by Searing75
 Sun Jun 01, 2014 7:11 am
Lamp chord is fine. I use fancy speaker wire from radio shack that was left over from years ago. The buzz is likely coming from another source? If its slight, I wouldn't worry. Tell us more about it, and we may be able to pin it down? Single coils? Grounding? Yada yada.
 #139485  by Winterland
 Sun Jun 01, 2014 10:52 am
It sounds like a buzz/whistle. Almost like something is spinning? It gets louder when I turn up the MAC or SMS(front gain or back volume).I have a phiga bolt and a wolf each with an obel and buffer 3 split humbuckers bolt/2 humbuckers and a single wolf. The mac is hooked from my SMS to the rca in on the mack by 1/4 inch adaptor. I then go from the 8hom on the left of the MAC, The right side common in MONO using the lamp chord. I then go to my JBL 2x12. Does that make sense? Oh I get major volume from the mac. Its just when I stop playing you hear the buzzzzzzzzzz.

really frustrating. thanks for your help!
 #139486  by tcsned
 Sun Jun 01, 2014 11:50 am
Does the noise happen absent of anything run into it? Is it consistently there when you're in a different house, club, etc.? Have you plugged an iPod or other audio source into it?

It should not be the cable, lamp cord, provided the gauge/length are copacetic. Have you made sure you are rubbing + to + and ground to ground? Flipping those can be a noise/dostortion issue.
 #139487  by Winterland
 Sun Jun 01, 2014 1:14 pm
When I remove the chord it is quite. I tried to flip the chord (left/right). You know how there are two
rows of the screws on the front of the mac. One is right and other left. I have the one side of the chord hooked to the left on the 8 ohm and the other side is hooked to right side on the common. Is that right?
I have two JBL e120's 16 ohm run parallel.
 #139488  by Winterland
 Sun Jun 01, 2014 1:34 pm
Ok I switched over to my MC 50 same issue, I switched the pre amp to my FYD and it was way noisier. I can
hear the buzzing way more and could not get a decent volume.

I then switched back to SMS and turned down the gain and it was less buzzy.

FYI
 #139489  by tcsned
 Sun Jun 01, 2014 2:04 pm
Winterland wrote:Ok I switched over to my MC 50 same issue, I switched the pre amp to my FYD and it was way noisier. I can
hear the buzzing way more and could not get a decent volume.

I then switched back to SMS and turned down the gain and it was less buzzy.

FYI
Ok, I think we can rule out the SMS as the cause. Are you running any effects? If so, try without the effects. Try a different speaker cable. Is this all happening plugged into the same outlet? You have 2 Macs? An MC50 and another? If so you can rule out the amps. If it's happening in 2 different amps, you can rule out the Macs. That leaves the guitar, the cables, the effects, or the speaker cable. Lamp cord should be fine, it's as good as anything else IMHO. It could still have a break in it or some other issue. I'd try different cables all the way around, pulling out effects, different guitar, different power source. This seem to be the only variables left I can think of.
 #139490  by Winterland
 Sun Jun 01, 2014 2:45 pm
I think it might be the rca cable with the 1/4 inch adapter or the speaker cable I made. Any suggestions for
either? Soon as I plugged in my FYD pre amp it was way worse than the SMS. I wonder why the noise would be so much more extreme? I will go try to reconfig again.

I have a gig coming up and switched from the rocktron to the MC250. What a difference IMHO I can't go back. It's like crack. I even tried my MC2100 and MC 50, but they are not like the 250. Why is that? Any ideas?
 #139492  by Searing75
 Sun Jun 01, 2014 4:51 pm
Wait! You have two jbl's on the 8 ohm tap? I assume they are wired in parralell? If so, you need the positive lead from your speakers to go to the 4ohm tap on the Mac, and the negative to the common.

As far as the buzz. How is the grounding in your house? Does it buzz like that at venues?
 #139495  by Winterland
 Sun Jun 01, 2014 5:58 pm
Its coming from the pedal board I think. I have an SBK pedal board model PS-45. I think that's
it. The stereo cable I got from AO is now not working...I am down the rabbit hole on this one.I have
volume its not seeing my pedals. I flip the switch on my guitar and the volume spikes but no effects.

The speakers are wired parallel 16 ohms.
 #139496  by Searing75
 Sun Jun 01, 2014 6:20 pm
If that pedal board has its own inputs and outputs, don't use them. Just plug straight into the effects, and your amp if you can. Just use the board to power, and secure your effects. This may help?
 #139497  by Winterland
 Sun Jun 01, 2014 6:25 pm
what about the stereo cable I have for the guitar. How do I Plug in both jacks? I have AO's
wheel pedal. I owe you a few beers for this!
 #139500  by Winterland
 Sun Jun 01, 2014 6:50 pm
Ok. I hooked up the AO pedal with the stereo cable AO made me and it works. The board is just a power source. I thought the board would function like AO's pedal. When I turn off the OBEL no pedals are seen.
just straight to amp. it actually sounds better straight(OBEL off) in much more punch and is not as thin.
I guess the OBEL will help me cut through much better too.
 #139519  by milobender
 Mon Jun 02, 2014 11:10 am
When I turn off the OBEL no pedals are seen.
just straight to amp. it actually sounds better straight(OBEL off) in much more punch and is not as thin.
I think that would indicate you are losing something in your effects chain somehow. Does it still sound 'thin' when you have the OBEL on and all the effects off/bypassed?
 #139563  by Winterland
 Tue Jun 03, 2014 1:44 pm
Yes. There is a difference. It sounds thinner. What can be wrong....Given your electrical expertise do you make pedal boards too? This is driving me crazy. My bolt you put the buffer and obel in is AWSOME!!