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Why use a pre-amp?

Discussion in 'Amps and Cabs [BG]' started by SirFunk, Jul 7, 2005.


  1. SirFunk

    SirFunk

    May 24, 2001
    Lincoln, NE
    Hi there, I'm just curious as to what the point of using a pre-amp is with EB and a good amp? I just got my iAmp 500 head and Wizzy 12" cab.. it sounds AMAZING... nice and puncy, yet good bass and not too-much high. I Love it.. and i'm playing my bass through it passively (ran out of 9v batteries)... I'm just wondering though.. what is the point? Is it really only for coloring the sound? If your amp has a good EQ there's really no point in using the EQ on the preamp, right? am i missing something?

    Thanks for the feedback,
    Jeff
     
  2. Juneau

    Juneau

    Jul 15, 2004
    Dallas, TX.
    The iAmp is a pre-amp and power amp built into one unit (a head), so your using a pre-amp as well.

    It is intended to color the sound with EQ as you mentioned, and if your "amp" (actually a head) has an EQ, it has a pre-amp. A power amp is just that, only power. A true power amp will not have any EQ controls on it, just gain, sometimes through multiple channels, thats about it.
     
  3. I've heard amazing sounding passive basses and amazing sounding active/preamp basses. The main advantage of having an onboard preamp to me is that you have the ability to adjust your tone 'on the fly' while playing... adding a little more bass when switching to single coil mode, for example (if your bass has that capability), rolling in a little mid for fingerstyle, etc.

    Also, an on-board preamp can result in a somewhat hotter signal going into the preamp of your head or component setup, which can make a preamp sound better (or at least different).

    Anthony Jackson doesn't even have a volume control on his Fodera... so it's hard to argue which way is 'better'. I just really like the ability to never turn around and mess with my amp once the gig starts.

    Ps I was assuming you were talking about an on-board preamp inside the control cavity
     
  4. Juneau

    Juneau

    Jul 15, 2004
    Dallas, TX.
    Ahh I see I may have misunderstood your question after seeing Kjung's response. I didnt realize you were asking about the point of an ON-board pre-amp if you have an OUT-board on your Amp/Head.

    Like Kjung states, its just for convenience sake. Plus you have minimal controls on the bass, while having more exact controls on the amp for tweaking. Or it may be the other way around, you have every control at your fingertips, and leave your pre-amp set pretty much flat. All pre-amps have a colour to them though, even set flat. So you might run your bass with all the bells and whistles on board pre-amp, into an outboard that was set flat, but still coloured your tone a tad and gave you THE sound you were after.

    Another reason is if you have more than one bass like me. I want an out-board pre that sounds good set flat for my active bass with all the onboard controls, but I also want it to be able to shape the tone of my passive bass if I choose.
     
  5. Tash

    Tash

    Feb 13, 2005
    Bel Air Maryland
    The biggest reason is power. How many watts is your head, 500? The most powerful head I know of is the SVT4 Pro, which maxes at 1600 peak. If you need more power than that you need a high power power amp. QSC, Crown, Mackie and the like have power amps that push thousands of watts, but they lack color and control over your tone.

    That's what a preamp is for. Get the preamp of your choise and couple it with a high power power amp and you can push exactly the tone you want into very high pwer levels.

    They other big use for preamps is recording direct. Its not uncommon for session or live fill in guys to carry nothing but a bass and preamp to a gig or studio session. If you get the sound you want from your chosen pre you can drop right into the board and record without the hassel of moving, setting up and micing a full sized amp.

    Same with a live situation where you drop straight into the PA.

    Just a couple reasons people use pres. If you have a head that give you great tone then you don't really need one. But heads don't cut it in all situations. Also not everyone likes the tone of their head, or can use it for every possible application. If I had a really high fi clean head like a GK I might want a tube pre in the rack to give me the option of adding some warm grit if the situation demanded it.

    Right now I don't even own a real amp. My playing is done with a digital amp modeler (essentially a preamp) through my studio mixer and monitors. Sounds great, I can get a huge range of fun tones and I don't need to worry about an amp. I'm getting one though, because my drummer's bass amp doesn't cut it. Its got volume for rehersals but weak tone and there's no way I could gig with it. So I'll be getting a GK1001RB-II once I have the funds, but as I said before I might still use the preamp to give me more variety.

    Edit: Oops, I too thought you were talking about outboard pres. I will leave me response intact for the benfit of anyone who might have a simillar questions and actually uses the search function.
     
  6. JMX

    JMX Vorsprung durch Technik

    Sep 4, 2000
    Cologne, Germany
    One advantage is that the low impedance output of an onboard preamp prevents possible loss of highs due to cable impedance.
     
  7. Here's a good reason to use the onboard preamp - if you are DI'ing your bass to the desk and then splitting the signal to your amp for onstage monitoring, then it lets you send a hotter signal that you have the ability to eq, to the desk. then the preamp in your head can colour the same signal for your onstage sound, while the sound engineer at the desk can use the straight signal from your bass to mix front of house...
     
  8. SirFunk

    SirFunk

    May 24, 2001
    Lincoln, NE
    Wow, ok, Thanks guys. I didn't really specify onboard or outboard.. but i guess i meant either way. So i guess in my situation i don't really need one (for electric atleast, DB might be another story) this iAmp is a wonderful head.... it's nice and compact i would definitely use the DI on it if i was doing any recording... or i'd send the DI to a PA if i'm playing a big show.. so i guess it's all i need. Having controls right at your fingertips is handy however, i might invest in some 9v's for my carvin and keep it mostly flat unless i need otherwise.

    thanks again,
    Jeff