Agree - my MB200 sounds nothing like that. If mine sounded like that (and if I hadn't bought it used) I'd send it back in a heartbeat.
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GK MB200 Hiss
- Thread starter drpepper
- Start date
Agree - my MB200 sounds nothing like that. If mine sounded like that (and if I hadn't bought it used) I'd send it back in a heartbeat.
Sometimes cheap is cheap. I returned some Ampeg stuff and MF accidentally showed me their cost on the invoice. I'm amazed at how little money it takes to produce these Chinese amps. So it's not surprising that it's hit or miss.
I'm seeing shuttle 9's go for $500 in the classifieds. You might keep your eyes open for a good used backup. With the new Genz stuff out I predict many upgraders will be dumping their still very nice stuff to move up.
I find this very interesting. I have an MB500 as my main amp right now and have not noticed this issue. In fact I found it quite quiet. There may be a pretty wide range of acceptable QC in these it seems. I am going to listen a little closer next week to see if there is anything noticable that I may have been ignoring.
The great variance in reported noise problems with these heads suggests a manufacturing quality control issue rather than something inherent in the design. As Tom mentions, the change in production to the US that starts next week (if I remember Tom's post correctly in another thread) should hopefully tighten things up.
There is a 60 Hz hum present both before and after you make the switch, so that argues for some grounding issues going on.
Next, I'll defer to those with specific knowledge of these small, high power amps or maybe even more specifically the MB200, but is it a good idea to have them powered up with no load? I would never switch the cab cable from one powered amp to another powered amp with the power left on both.
Next, I heard no hiss but YouTube is not an ideal acoustic environment necessarily.
There is a 60 Hz hum present both before and after you make the switch, so that argues for some grounding issues going on.
Next, I'll defer to those with specific knowledge of these small, high power amps or maybe even more specifically the MB200, but is it a good idea to have them powered up with no load? I would never switch the cab cable from one powered amp to another powered amp with the power left on both.
Next, I heard no hiss but YouTube is not an ideal acoustic environment necessarily.
No problem running a solid state amp without a load. With tube amps, not a good idea.
There is a 60 Hz hum present both before and after you make the switch, so that argues for some grounding issues going on.
Next, I'll defer to those with specific knowledge of these small, high power amps or maybe even more specifically the MB200, but is it a good idea to have them powered up with no load? I would never switch the cab cable from one powered amp to another powered amp with the power left on both.
Next, I heard no hiss but YouTube is not an ideal acoustic environment necessarily.
As you point out, and as I said from the outset, this was not an ideal audio recording. It's certainly not a diagnostic recording and isn't even really ideal for illustrating what was intended...which was to show that the MB200 is making a noise that it shouldn't be making and that the RH450 is not making in the same circumstance.
I don't know how you can move from that to believing that you can glean anything from a "60 Hz hum."
And SpeakOn...
"Because of the design of the connectors, there is no possibility for accidental human touch, nor do the connectors short out during connection or disconnection, making the SpeakOn system safe for connecting or disconnecting while amplifier power is on."
Yeah, a used something in the sub-$300 range might be the ticket. There was a LMII that I should have jumped on.
The line-in and headphones are something that really add usefulness though.
It's going back, but I may spin the wheel on another one - still working it out.
I to have both an MB200 and 500 and haven't had this issue with either of them. My MB200 is one of the older models with the two combo jacks. If I was you and this was something you wanted, exchange it for a new one. You won't be disappointed with these amps and as many people in this forum can contest, GK service and quality is very high. It truly is a wicked little amp.
FWIW i had the same issue when i first recieved mine,
called GK spoke to Bryan,sent it back,apparently
it was a wire that was running underneth one of the
boards causing hum/hiss,its been dead quite since i
got it back,you may have gotten an older one that had
the issue,newer ones should have this addressed.
+1 to Rocker47 post
called GK spoke to Bryan,sent it back,apparently
it was a wire that was running underneth one of the
boards causing hum/hiss,its been dead quite since i
got it back,you may have gotten an older one that had
the issue,newer ones should have this addressed.
+1 to Rocker47 post
A specific cause and solution...interesting.
So, when was it that you got yours? As I believe I said, I like everything about the amp so far, except for the noise.
It might be worth it to move methodically through this and see if I can deal directly with GK on getting it resolved instead of just returning it or trying to exchange for another from MF.
Exchanging with MF is SO simple (especially with the trivial size and weight of that head). Given that this seems to be more of a 'production variation' issue, you have an excellent chance of 'getting a good one'. If the second one has a similar noise issue, then you can either return for a different brand, or contact GK. IMO.
Cable/wirie routing is a major root cause of noise in electronics manufacturing.
Sounds like they've seen this and know what to do.
drpepper:Mine was one of the first batch released,
GK is very much aware of this and have taken steps to
rectify the issue on the newer unitz,i would get another from MF,should be OK,if not then contact GK,this little amp
is worth its weight in gold..
Agreed that the exchange is easy. I'm really just not feeling (gut level) that my chances of getting a good one are excellent.
Not sure what to take from that. The one I just got doesn't have a date on it that I can read, but since these things have been moving pretty well, it seems reasonable to think it was made fairly recently.
Thanks again for the input. I think I'm pretty well settled on taking a stab at another unit from MF and just seeing if it's better.
If it hisses, send it back. Mine hissed like a box of snakes, and the replacement was dead silent. My MB 500 has a little hiss, but not bad. The hiss in the MB500 is in the poweramp because it does it in the efx return.
Wes
Wes
