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VT pedal overpowering the head?

I

iri5hpunk21

Feb 1, 2009
82
1
#1
So I've had the VT Bass pedal for a long time, and it sounds great but I'm always worried that since I'm running it in front of my head that I might be sending too much input level into the head and it could possibly damage it. My last (used) head died on me late last year so I've been kinda paranoid about that.

I have a Mesa M-pulse 600 with a Mesa Powerhouse 1200 cab.

http://www.mesaboogie.com/Product_Info/Bass_Amps/M-Pulse-600/M-Pulse600CloseUp.html

I usually have my bass volume at level 4, my gain on the head at around 1 o'clock and my output main i try to keep around the same. The bass, mid, and treble controls next to the gain are all also around 1 o'clock, the 5 band EQ I keep pretty flat at 12. for now, and the compressor is also at 12 o'clock for threshold and ratio.

How far do you guys think I could push the head?
 
#2
Untill it clips. ;)
A head can't be fried by too much input signal, but it will clip at some point (see guitar heads). I'd rather be worried about my speakers, these can (easily) be killed by too much bass/a too loud signal.
 
#3
Really? The last head I had was a solid state Euphonic audio iamp 600 and it had a little LED bar that would go red if I was giving it too much input. This is a tube head, to which i'm new to, and it doesnt have any such indicator...though the compressor light gets pretty red. I'm also fairly sure I've heard others speak of head getting killed by this. my last cab way out-latsted my last head
 
#4
It is totally impossible for a pedal to damage an amp head, unless you are talking about like firing the pedal from a cannon at close range, or unless the pedal is actually a power transformer delivering 1.21 jigawatts into the head.

Whoever told you you could damage the amp with clipping was wrong.
 
#5
Interesting. It always just sounded like if i were to crank the level and drive too high it would just make it freak out... well I guess this make it easier to dial in my tone without worrying about damaging the head..
 
#7
iri5hpunk21 said:
Really? The last head I had was a solid state Euphonic audio iamp 600 and it had a little LED bar that would go red if I was giving it too much input. This is a tube head, to which i'm new to, and it doesnt have any such indicator...though the compressor light gets pretty red. I'm also fairly sure I've heard others speak of head getting killed by this. my last cab way out-latsted my last head
Click to expand...

I like how you use the correct syntax to avoid a hanging preposition, then go ahead and hang it anyway. Don't sweat it, though. McCartney did it too: "And if this ever-changing world in which we live in ..."
 
#10
iri5hpunk21 said:
So I've had the VT Bass pedal for a long time, and it sounds great but I'm always worried that since I'm running it in front of my head that I might be sending too much input level into the head and it could possibly damage it. My last (used) head died on me late last year so I've been kinda paranoid about that.

I have a Mesa M-pulse 600 with a Mesa Powerhouse 1200 cab.

http://www.mesaboogie.com/Product_Info/Bass_Amps/M-Pulse-600/M-Pulse600CloseUp.html

I usually have my bass volume at level 4, my gain on the head at around 1 o'clock and my output main i try to keep around the same. The bass, mid, and treble controls next to the gain are all also around 1 o'clock, the 5 band EQ I keep pretty flat at 12. for now, and the compressor is also at 12 o'clock for threshold and ratio.

How far do you guys think I could push the head?
Click to expand...

From experience:
I own the Mesa Mpulse 600 Venture, and (although it's not my choice player anymore), I've never felt that I was pushing that amp to its limits before it became too loud to bear :D
(This is also with experience of the VT in front of the amp).

With 600 Watts you've definitely got the headroom. I wouldn't worry too much about it. You'll know when your amp starts sounding terrible, that maybe you're pushing it too hard - but I sincerely doubt it will be at the levels that you are running it at.
 
#11
I once pushed the preamp of my H&K Basskick 707 (transistor) 'till the sound was totally fuzzing out & sometimes couldn't clip more (or something like that) and therefore not sending any signal to the power amp. Still works like a charm (except some scratchy pots, which I have to change some time ;)).
 
#12
I don't have any input for you, but since people here are running the VT, I was curious if you could explain the purpose or theory behind running the pedal in front of the amp as opposed to after the amp. Can this only be done when using a PA. I am assuming that there is not a different place to plug this VT into an amp to make it come before the amp without the VT or amp being plugged into any other power source....but/and I could most definately be wrong.
 
#13
Howdy:

You know, the MP600 is one loud-ass head. And it's as robust as most any head out there...

It doesn't have clip lights on the input because it's got toobz, and it sounds really kinda good with the right amount of clipping on the preamp stage.

Now, having said that, There used to be a combination of effects in my chain on my MP600 that would push it into thermal protect.

I wrote about it here and here .

Think about it - the GAIN and MASTER settings have to be set together, and if you set it for relatively high gain, you can only push the master so hi before the mosfets will get hot.

If the knobs run from 7:30 to 4:30 on the dial, then setting gain and volume on 1'oclock setting is what, about 75%? So you're running the head pretty hard, 4 ohms I'm sure, and then you start stomping on effects that increase the gain. It gets louder, because in effect (no pun intended) you have reached over and turned up the input gain!

In my case, I was running with input gain 1-2 o'clock and up to about 1 o'clock on the master. It was mega-supra loud, and really really bassy (the band I was in at the time was insane) and when I'd hit the some of the effects, clearly it got louder still and then you could hear the <click> and have to wait a few seconds for the TP circuit to click back in.

So what happened? The effects I thought were causing the problem weren't. At the time I couldn't find the culprit, so I just started dropping the master a bit for those songs so it wouldn't die. After a board re-vamping where I removed some pedals I didn't use frequently, and which did not have true bypass, the problem went away altogether. It's been about two years and I have had no issues.

Simple rule is this - the lower your gain the higher you can crank the master. Those that use the MP600 for clean tones can get incredible booty out of that thing by running gain lower than noon and cranking up the master.

I think the MP600 has kind of a weak fan - I'll bet if you modded it with a higher RPM fan, along with some switched resistors to slow it down at low volume, you could squeeze more out of it.

Good Luck, have fun, protect your ears.
 
#15
subopposite said:
I don't have any input for you, but since people here are running the VT, I was curious if you could explain the purpose or theory behind running the pedal in front of the amp as opposed to after the amp. Can this only be done when using a PA. I am assuming that there is not a different place to plug this VT into an amp to make it come before the amp without the VT or amp being plugged into any other power source....but/and I could most definately be wrong.
Click to expand...

I hope you're talking about running the pedal after the pre-amp and not the power amp... I can think of no better way to fry your pedal (and possibly your speakers) than chucking it after the power amp.
 
#16
subopposite said:
I don't have any input for you, but since people here are running the VT, I was curious if you could explain the purpose or theory behind running the pedal in front of the amp as opposed to after the amp. Can this only be done when using a PA. I am assuming that there is not a different place to plug this VT into an amp to make it come before the amp without the VT or amp being plugged into any other power source....but/and I could most definately be wrong.
Click to expand...

I'm just going to set this issue out from ground up ;)

Okay so think about a modular rig like a rack system. You have your pre-amp and your power-amp separately right? Now just like manufacturers like to package things together such as the amp with the cab to make a combo, you also mostly find the pre-amp and the power-amp packaged together within a "bass head" or "amp". But in reality these separate components do exist within the head.

The VT bass pedal is in essence not only a stomp box, but a stand alone preamp. This is highlighted by the use of the vt bass with a poweramp as many do, or even in the incorporation of the vt bass in the new VT bass 300 amp (check out Invalid Link Removed).

So therefore rather than having two preamps going as you would when you plug the VT in the front of your amp, for optimal results what you should do (according to Tech21) is defeat the pre-amp in your bass head and have only the VT bass acting. How do you do this? Usually by plugging the VT bass into the effects return, in your bass head, which usually, but not always, happens after the preamp. If this isn't an option the alternative is to plug it into the front and set the EQ on the head as flat as possible. Some amps do have a dedicated pre-amp in port.

However in reality the sound of two pre-amps could be awesome, so its best to experiment. As Jake of bass said though, you do not want to plug the speaker out of your head into the VT bass! This would send ~300 watts into the VT bass and probably fry it!

I have just gotten my VTD, and I have a GK 700RBI and I'm still figuring out how I'm going to do my chain. Hrm....
 
#17
I've always run my effects before the pre-amp, mainly because it's simpler in the chain and I don't need to run an extra lead from my head to my effects (I use a Markbass LMII). To me this works fine and as I have a clip LED I can control the pre-amp gain stage after my effects.

FYI, others have reported running the VTD before the pre-amp sounds better than using the effects loop. I can't add my 2 cents here though as I haven't tried the loop.
 
#18
Ok gang... there is a simple solution to all this. Set the output of the VT Bass when ON to match the output of your bass when the VT is turned OFF. If you are putting the same level of signal into the amp as affected by the VT Bass as it would be getting straight from the bass itself, your worries are over. If you are using the VT as a true preamp to gain-stage your bass and increase the output of the bass itself then this suggestion isn't worth much, I guess. Regardless, just be reasonable about where you set the output of the VT. If you're pushing the output of the VT to the max then of course it will be WAY hot at the amp input and could very well clip/overload the gain stage at very low levels on the amp itself. Matching unaffected vs. affected volumes has always been 'normal' practice as I've been told.
 

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