DI vs. Preamp

Discussion in 'Effects [BG]' started by Bob Rogers, Mar 7, 2005.

  1. Bob Rogers

    Bob Rogers Left is Right

    Feb 26, 2005
    Blacksburg, Virginia
    Let me see if I have this straight. The primary job of a preamp is to take an instrument/mic level (-20 dBu) signal and increase the signal level to line level (+4dBu). The primary job of a DI is to take an unbalanced high impedence signal and put out a low impedance balanced signal. Is this correct?

    It seems to me that a large number of devices do both, but are labled Preamp or DI not Preamp/DI. Any real reason for this other than packaging or marketing?
  2. burk48237

    burk48237 Supporting Member

    Nov 22, 2004
    Oak Park, MI
    Usually the difference is that most Pre amps provide some tone shaping capabilities, sometimes even full on parametric EQ's. And although many of them have direct outs that is not there primary purpose. Some pre amps have very good DI's built into them but many don't, if they skimp on the componants it will show. The one that really blurs the line is the Avalon U5, I bought it for it's DI capabilities and now use it as my Pre Amp. There are many very good dedicated DI's (Radial, Demeter tube-they make a pre also, Countryman, Grove Tube Brick). There are also some smaller Pres/DI's like the Sadowsky and the San Amp, I know they are pretty good pres but I am not familiar with there DI capabilities. The 539$ for the U5 sounds like a lot of money for a DI but when you hear it you wonder how you played without it. My pet peave is guys that spend 3 grand on amp 2 grand on a bass and then plug into the 29.99 direct box. Unless your goal is just sounding good on stage, thats pure stupidity!
  3. Tedintheshed

    Tedintheshed Banned

    Oct 8, 2004
    Columbus, Ohio
    You are right- there are a large number that does both. The aforementioned Avalon, the Sansamp and the MXR M-80 Bass DI+ all do it all. Some would even classify the Demeter VBP-1 as this also, considering many came stock with a Jensen Output transformer.

    To me, as long as is sounds good such verstility can be a Godsend. As an example- I use my MXR M-80primarily for distortion but if my pre-amp goes down then I am set- I can use it as my pre and still have a line out for my soundman.

  4. jvtwin

    jvtwin What it needs is a little more cowbell

    Jan 26, 2001
    LA Calif.
    This is a very cool thread! I've often wondered and thought about doing away with my Ashdown RPM1 pre and go to just using a D.I. I mean for the most part I just play with my pre in a flat signal postion anyways and do most of my tone shaping off my bass. (active PU's) I've really don't use the tone shaping unless I play one of my older basses and even then, I not really moving around much (tone wise) I've heard of the Avalon and was also wondering about Aguilar's D.I. as well. Any thoughts from users?

    It would be nice to trim a little more weight off my gear.