Markbass mini CMD 121P problem

The VLE is your friend. Remember, this control is designed to work as a tweeter attenuator on the front of the amp. Dialing it in at about 9 o'clock will take the upper edge off your tone, and quiet a lot of the noise you have in your signal path.

Also, you should NEVER turn the VPF up past around 10 o'clock. Besides scooping the tone, it will add lots of upper treble to you tone if you turn it up to noon or past... not a good thing with a piezo tweeter with no attenuator.

Finally, the active treble control on the amp is set very high (10K shelving), and is also good for controlling upper level treble response without sucking upper mids out of your tone... a slight decrease in the is control will also help a lot with your situation.

That all being said, those Markbass cabs with the cheap piezo tweeters and no attenuators are not the best design I've seen. However, you have LOT's of control over the upper treble that can cause issues with a piezo type tweeter, especially when recording/mic'ing a cab.

Hope that helps. Of course, the best solution is to use the post EQ direct out!

 

ah, not sure about that. My LMII is very quiet through my cabs with the tweeters set at noon or so, even with the volume cranked a bit. Alexclaber or one of the other EE oriented guys mentioned that piezo tweeters extend much higher into the highest treble region than other tweeter designs, and hence can sound more 'hissy' given that very high upper treble, especially if they don't have an attenuator.

 

I have one and the tweeter hisses a little. Never been a big deal to me. I roll off the treble with the VLE, and even when I didn't, you couldn't hear it in a playing situation.

 

If I turn the volumes up high I can hear a little hiss with my ear to the tweeter.
Under normal use (gigging) I hear no hiss.

With the volumes off I hear no hiss at all. Off course, I'm not recording, just listening.
Hope this helps

 

In a very quiet room, I can hear a slight hiss from the tweeter
with the master volume off. It gets louder as I turn up the
master volume. Its nothing you'd ever hear in a live context,
but from two feet away in a quiet room I can just hear it.

The lack of attenuation of the tweeter is the only thing I
don't like about this combo.

 

Did you read my post?

 

I just got one of these today. So far I haven't noticed any hissing or humming. I bought the floor model since it was the last one. So far so good.

 

The problem with totally defeating the tweeter is that the high end in the speaker itself cuts off highs at 3.5K and sounds even lower. So if you want any highs, you pretty much have to have the tweeter on a little. But I've tried micing it for recording, and I don't hear the hiss, even when the tweeter is up all the way. But if it bothers you, the best I can tell you is to gate it.

 

You can pull the tweeter off the crossover, but it voids the warranty. You can put a sponge over the tweeter (this works very well, BTW). Or you can use the VLE. I use the VLE because the tonal effect of using it works out to the same as the other two solutions.

 

There should be NO sound with the volume and gains down. I have to turn the master up all the way to hear hiss.

Do you have anything plugged into the effects loop? I don't know if this is before or after the master volume control. If it is post, then something else could be causing the noise.

Otherwise, If you are within the 30 days, take it back to GC and get another one. First problem I have heard of.

 

Ditto--the VLE essentially IS your tweeter attenuator on these.

 

Consider the problem coming from your bass. I don't know how, but it has to come from somewhere, doesn't it?

 

He's talking about no bass plugged in and all volume knobs
down.