-10dB Pad Option on Input

[backagain1]

Many amps have a -10dB pad or a 14dB option on the input. I understand that these inputs can be used if you have a bass guitar with active circuitry with a hot output, like a MusicMan.

Doesn't plugging into the padded input on an amp defeat the purposes of having a bass with active circuitry?

Do you use the padded input with your EB bass?

What am I missing here?

Thanks,

backagain1

 

[tkarter]

I use the pad on mine. Both SR5 and Bongo 5H. The reason I use it it so that I can run the amp gain a little higher and get the sound I want from the amp. When I tried not running it the amp needed none to little preamp gain before clipping would be encountered.

As so defeating the purpose of the preamp in the bass I just don't believe it does I haven't any logical explanation of my supposition there.

IMHO

tk

 

[BigStrings]

I have a GK 800RB and I've tried it both ways with my Sterling and my HH Bongo 4. With the pad button pushed in it sounds fine but I find that it just sounds punchier not using the pad button. I don't have a clip indicator light but have no problem overdriving the preamp, it just sounds super clean and punchy. If the particular amp you use clips a little early for you, you have no choice but to use the pad button.

 

[Hutton]

My Walkabout Scout has two inputs. One for active and one for passive. I take it that this is the same thing as you are talking about. I must admit that I have never tried plugging my ray into the passive input. I must give it a try and see what happens!

 

[Psycho Ward]

My Walkabout Scout has two inputs. One for active and one for passive. I take it that this is the same thing as you are talking about. I must admit that I have never tried plugging my ray into the passive input. I must give it a try and see what happens!

BOOM!

 

[Hutton]

Okay Psycho I get the message. Thanks for the timely intervention. It surely wouldn't go 'BOOM'. What if I did it by mistake?

 

[niftydog]

All it is there for is to prevent the preamp overdriving from the high output of an active bass. If your active bass doesn't overdrive the preamp, even when plugged into the non-attenuated socket, then use either one you want.

Done sensibly, you won't blow anything up.

 

[strummer]

Many amps have a -10dB pad or a 14dB option on the input. I understand that these inputs can be used if you have a bass guitar with active circuitry with a hot output, like a MusicMan.

Doesn't plugging into the padded input on an amp defeat the purposes of having a bass with active circuitry?

Do you use the padded input with your EB bass?

What am I missing here?

Thanks,

backagain1

On MY AG500 I use the pad, because otherwise I can't hardly turn the gain knob at all without unwanted distortion.

 

[RockinRayDuke]

I never use that "active" jack. No problems with the MGBongo.

 

[SteveB]

Lowering the gain on the amp (via the pad) versus lowering the gain on the instrument:

The signal being amplified is shaped more by the instrument (which is running 'full') rather than the amplifier's pre-amp. This should result in a better signal-to-noise ratio as well.

We're talking about basic gain structure here. Generally you want the sound source running at almost it's max output (sometimes a little less to keep the source itself from distorting). Then, you 'trim' the input signal level at the source of amplification, to keep the sound source from clipping/distorting the amp's input.

Hope that helped a little.

Addendum:

For clarity... if you start with a low signal, and then make the amp do all the work of amlipfying the signal, you also amplify any noise along with the signal.

If you start with a 'hotter' signal, there's much more signal than noise, and the amp doesn't need to amplify the signal (and noise) as much before you 'hear' the signal. This results in a lower 'signal to noise' ratio, which is a good thing.

 

[Fuzzy Dustmite]

I use an 800rb as well, and don't pad the input. Sometimes I use an ODB-3, and with the padded input, it seems to cut out some of the overdrive as well.

 

[Psycho Ward]

Seems like I get more request to pad my output...

 

[Dees]

Almost all the amps have such an option, and I was surprised not to find this option on my EBS Fafner amp. Only one input, no button. But I don't miss the option, so I suppose it's not necessary

 

[backagain1]

Lowering the gain on the amp (via the pad) versus lowering the gain on the instrument:

The signal being amplified is shaped more by the instrument (which is running 'full') rather than the amplifier's pre-amp. This should result in a better signal-to-noise ratio as well.

We're talking about basic gain structure here. Generally you want the sound source running at almost it's max output (sometimes a little less to keep the source itself from distorting). Then, you 'trim' the input signal level at the source of amplification, to keep the sound source from clipping/distorting the amp's input.

Hope that helped a little.

Addendum:

For clarity... if you start with a low signal, and then make the amp do all the work of amlipfying the signal, you also amplify any noise along with the signal.

If you start with a 'hotter' signal, there's much more signal than noise, and the amp doesn't need to amplify the signal (and noise) as much before you 'hear' the signal. This results in a lower 'signal to noise' ratio, which is a good thing.

Very nice explanation. Thanks!!

backagain1

 

[SteveB]

Very nice explanation. Thanks!!

backagain1

Glad to be of service. There are lots of guys (and perhaps girls) on this forum who are eminently more qualified than I am to speak about these subjects.. so if you want more technical detail just say so and someone will delve as deep as you care to go.