Using laptop as an amplifier

Discussion in 'Guitar Gear Talk Forum' started by wisevijay, Oct 3, 2009.

  1. wisevijay

    wisevijay newbombayrox

    I have a Givson acoustic guitar without pickups.I wanted to use my laptop as an amplifier/effects processor.The software i m using is AmpliTube.
    I tried using a microphone as an input but there is too much disturbance and it even amplifies the sound of my feet tapping!
    I saw a 'clip on pickup' at a guitar shop n it worked fine with a real amplifier.
    it looks like this

    Will using a pick up work on a laptop as it only has 2 inputs viz. speakers n mic. n no line in.i will be using a 1/4 to 1/8 conversion cable to plug it into my laptop microphone input.

    Will there be any lag in output?has any1 successfully tried a s/w as an amp/processor??
  2. ambush

    ambush _RASTA_man_

    The sound quality would be horrible. i doubt you will be able to hear anything above the hiss and the static. But then its not a expensive gear(the pick up), So go ahead and try it.

    You have to install the asio4all driver to reduce the latency.
  3. gpt

    gpt New Member

    trust me dude .. its gonna suck balls
    you better of getting a real amp
    ... you might end up screwing up ur laptop's speaker
  4. wisevijay

    wisevijay newbombayrox

    hmmm....thanx for the info...
    yeah its nt an expensive equipment..was gna buy it any way...
    will try with the driver update/install.
  5. flood

    flood New Member

    the lag in output is not what i'd be wworried about. it'll just sound like shit slightly later.

    the best way to go is with a decent quality microphone.

    as always with similiar queries, i strongly discourage using distortion on an acoustic guitar. i've done all these experiments with all sorts of pickups, and none of them sounded even passable. unless you're out to make noise rock/industrial/harshcore i would tell you to fuhgeddaboutit.
  6. wisevijay

    wisevijay newbombayrox

    thnx...yea..i know latency can be rectified..neways the pickup i was talkin abt costs 150 no harm investing in it...will be buying an amp later ne ways.
    will be buying it now n will post abt it later this evening..
  7. flood

    flood New Member

    i've owned a couple of those pickups. the thing is: you are not going to be able to avoid feedback (UNLESS you're using headphones, of course, or playing at extremely low volumes) since the instrument you are amplifying is an acoustic guitar with a resonant chamber that is VERY prone to environmental sounds.

    also, they sound quite nasty, have a very low output (since acoustic guitar strings are not optimized for electromagnetic properties) and can be horribly microphonic.

    perfect for me cause i feed off noise, hum, feedback and other nasty sounds in general. don't know how good that is for you though.
  8. flood

    flood New Member

    holy shit i forgot to check the picture. that's a piezo pickup; i for some reason though you were buyng a magnetic soundhole pickup. it's going to sound even worse than i thought! also, be judicious with volume levels or your speakers will take a mothering (which i suspect they will from the feedback).
    wisevijay likes this.
  9. wisevijay

    wisevijay newbombayrox

    well...i bought the piezo pickup....pluged it into my laptop....installed AISO drivers...started AmpliTube...n no matter what settings i use..i get this annoying clipping sound...with or without the pickup or mic pluged in!!!

    i have vista home premium....troubleshooting n google says i need to disable MS GS Software Wavetable Synth which is not possible in vista!!!
    what the hell m i supposed to do !
  10. thehundredthone

    thehundredthone New Member

    You're probably plugged into the mic-in on the laptop. Go to the mixer and switch off the 20dB gain and see if it helps.
    wisevijay likes this.
  11. flood

    flood New Member

    he only has the mic input. piezo PUP into mic input x-(

    vijay, i hate to be the messenger, but this little experiment of yours is not the best idea. believe me, i've done it. many a time! accept your acoustic for what it is, and buy an electric when the time comes.

    for a little primer (i'm going to brazenly assume that you're a non-technical person, so apologies if you're the second coming of feynman) on what you would need to do to make it sound even haflway acceptable:
    1. the element in that clamp is called a piezoelement. it exploits the piezoelectric effect to send a voltage as an output - basically, it converts vibrations into an electric signal.
    2. the problem with piezoelements is that they have a very high output impedance (frequency dependent resistance, for simplicity's sake). while the signal they generate can be very large, the impedance causes a problem in that it cannot be matched to conventional signal levels. generally speaking, impedance in ascending order:

    - microphones
    - line level
    - instrument level
    - piezo

    3. it is very essential to match the impedance so signals of different types and from different sources can be amplified. you would normally want to bring them to line level, on which a lot of equipment operates - e.g. mixers, line inputs on PCs etc. so you need a preamplifier, or a buffer. in this case, you would need a buffer with a very high input impedance and a very low output impedance.

    4. fortunately, piezo pickup buffers are very simple to build. if you're handy with a soldering iron, or know someone who is, you can do it yourself with very few parts.

    5. at the end of the day, you will have a much better acoustic guitar sound being recorded... however, it will still NOT sound good with amplitube etc. an acoustic is an acoustic, and an electric is an electric, and unless you're playing that taylor hybrid, the twain shall never meet. accept each type for what it is.

    matching the impedance
  12. wisevijay

    wisevijay newbombayrox

    thanx for all the info...n btw i m a technical person..doin my mechanical engineering rite now,no offense taken tough!
    i wasnt gna accept defeat until i read ur last post...i surely dosent work well with does tough with Audacity..which can b used only to realtime procesing...but i managed to eliminate the latency and the output is good.

    well,i've given up on using amplitube but theres this problem thats bothering me.
    I am using Realtek HD audio drivers+ASIO4all+Amplitube..n on startin amplitube all i get is a clipping sound n my input bar shows 100%..evn with the guitar unplugged!
    also in the audio settings for amplitube in asio it shows realtek front Mic input 1 & Mic input 2.y the 2 inputs??i have disabled the inbuilt mic.

  13. thehundredthone

    thehundredthone New Member

    Flood, you mean impedance bridging :p

    Cutting the 20dB boost should allow him to record/monitor the acoustic guitar at least (if he wants to that is).

    @wisevijay: The only thing that could come somewhat close to a good distorted sound would be if you recorded the clean guitar and then implemented the effects. But again that's only useful if you're recording.
  14. wisevijay

    wisevijay newbombayrox

    i managed to record n also play without latency but only as an acoustic guitar/clean...
    ne ways it was worth trying!

    thanx for all ur help.
  15. wisevijay

    wisevijay newbombayrox

    okay every one!!!
    my acoustic guitar+piezo pickup+Amplitube works!!!!!!

    wat i did is
    1.downloaded the latest realtek HD audio drivers
    2.Download ASIO4all driver amplitube audio prefrence select ASIO
    4.then in ASIO control panel use the foll settings
    i.keep only your audio output in input active n disable evrything else.
    ii.dont use 'Allow pull mode or WaveRT'
    iii.Latecny settings according to ur pc.

    n u r ready!!!there is zero latency..n i have external BOSE sepakers attached to my laptop so for me atleast the sound is satisfactory.a little fine tuning here n there will get u a decent sound with an acoustic guitar...with an electric guitar its as good as external hardware.

    will post a recording asap...

  16. wisevijay

    wisevijay newbombayrox

    i read ur posts here n man i m impressed!!i am not dat good of a guitar player n neither do i plan to invest in any kind of hardware rite now...dats y i m more than happy to achieve some amount of success with the piezo pickup+amplitube/audacity/other softwares!!

    thank you for all the advice,suggestions and info.
    i wont be surprised if someday people would pay u for ur advise!


Share This Page