Input : to use the -15 db pad or not to ?

[Inconnu]

Hi !

I was wondering... I'f got a -15 db switch for the input of my amp. When switched off, I'm able not to peak at, say, around 25% of the gain up. Otherwise, with the pad on, I can get the gain at around 60%. I haven't noticed a difference in sound much... is there a technical reason why I should use one or the other option ?

[Jason P Bass]

I think no.

If clipping is a problem, use the -15.

If weak signal is a problem, use the 0.

If neither is a problem, bust out some funk.

[bongomania]

^^^ Good answer!

[PilbaraBass]

personally...I'd use the pad as it is impedence matching (most likely) and turn the input knob up more...

But either way is fine...rock on...

[lowendgenerator]

I have a GK head, and I notice that when I hit that pad button, my tone goes to poop. I mean REALLY goes to poop. I lose all my highs and definition, it sounds like someone threw a wet blanket over my ears. Sup with that, shouldn't it just get quieter?

[Sartori]

When I had an SVT-350 it had one of those pads. I used it as a "much quieter" button for plugging in and unplugging my bass and tuning and such.

[bongomania]

Originally Posted by PilbaraBass

personally...I'd use the pad as it is impedence matching (most likely)

I've heard from several amp brands and repair-people that most of those pads are nothing more than a resistor. No impedance matching, except insofar as the resistor lowers the input impedance some, making it (generally) better suited to active basses (or otherwise lo-z signals). In fact the only amp brand I know of that claims anything more than just a resistor in the pad is Phil Jones.

[bongomania]

Originally Posted by lowendgenerator

I have a GK head, and I notice that when I hit that pad button, my tone goes to poop. I mean REALLY goes to poop. I lose all my highs and definition, it sounds like someone threw a wet blanket over my ears. Sup with that, shouldn't it just get quieter?

Are you using a passive bass?

[Bassamatic]

The pad can ve a simple resistor across the input. The problem with this is that it can load your passive pickups and affect the tone - kinda like an extreme example of 500k vs. 250K pot. It should not be necessary to use it except with hot active basses, and they don't care about the resistor.

[IvanMike]

input pads are like active input jacks - only use them if your signal is so hot is melts basalt.

[rbonner]

There's times with special effects and OLD STYLE active basses that had preamps that could actually drive a power amp without a preamp... When you have one of those suckers use the -X input pad button. And GIO is right about passive pickups and pads.

Basic rules, your bass turned all the way up: Gives you the best signal to noise ratio. That's part of why Lowend loses some zing.

Then adjust the gain for the proper drive to the preamp section.

If you have one of those firebasses from the early 80's go buy a Crown 8000 watt amp and drive it direct. Cause you dont need no stinken preamp.

BOB

[KJung]

Originally Posted by Inconnu

Hi !

I was wondering... I'f got a -15 db switch for the input of my amp. When switched off, I'm able not to peak at, say, around 25% of the gain up. Otherwise, with the pad on, I can get the gain at around 60%. I haven't noticed a difference in sound much... is there a technical reason why I should use one or the other option ?

In general, no problem either way. That pad puts some extra circuitry between your bass and amp, so I always go with a non-padded signal.

The only real reason to use that padded input is if you have either a VERY hot output bass (active or passive) and/or very aggressive technique that results in your preamp clipping even with the gain turned down almost all the way.

[JimmyM]

ya, don't use the active input unless you absolutely have to. like it's a desperate situation and you've exhausted all other possibilities and that's the only thing on earth that will work.

[brattbugg@sbcgl]

Originally Posted by lowendgenerator

I have a GK head, and I notice that when I hit that pad button, my tone goes to poop. I mean REALLY goes to poop. I lose all my highs and definition, it sounds like someone threw a wet blanket over my ears. Sup with that, shouldn't it just get quieter?

I have a 1001rbll and if you push the pad in, you really have to turn up the input to get the tone back. What I do is run my power amp hot, like at 3-4 o'clock. Then I bring the input up and before you know it, Im pumpin. Now I do notice with the GK more than any other amp I've had, knocking the impedance down with another cab, makes it much louder. I dont use the pad.

[IvanMike]

Originally Posted by KJung

In general, no problem either way. That pad puts some extra circuitry between your bass and amp, so I always go with a non-padded signal.

The only real reason to use that padded input is if you have either a VERY hot output bass (active or passive) and/or very aggressive technique that results in your preamp clipping even with the gain turned down almost all the way.

some of those pads or active inputs or pads have a bit of a tone suck. The active input on SWR amps acts as a bit of a treble cut even with the gain turned back up to an acceptable level.

[groooooove]

Originally Posted by IvanMike

some of those pads or active inputs or pads have a bit of a tone suck. The active input on SWR amps acts as a bit of a treble cut even with the gain turned back up to an acceptable level.

i've heard this too on a GK head before.

i never use the input pad.. and my signal can make anything clip.. but ive never had a problem.

[nsmar4211]

On my ampeg B2r head I have to use the pad button with all my active basses or I clip just looking at the darn bass. My passive basses don't need it.

Reminds me, I keep having clipping issues.... think I need to check my combo amp for a passive/active button.....

[lowendgenerator]

Originally Posted by bongomania

Are you using a passive bass?

Negative. I am using a Lakland 44-01 or a jazz deluxe. I don't have a problem with premature clipping with either bass. Ironically, the only bass to ever light up my clip light was a POS Squier P with a dimarzio pickup in it. That sucker was LOUD!

[bongomania]

Okey-doke. As you probably figured from the couple posts following mine, a common reason for the pad (or "active input") to sound bad is if it lowers the input impedance too much relative to a passive bass. But in your case, I guess it must just be a badly-designed pad. *shrug*