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Lexicon Alpha recording problems

Discussion in 'Recording' started by Quinnc11, Mar 12, 2011.

  1. Quinnc11

    Quinnc11 Guest

    Hey there,
    Kinda new to the whole recording process but ran into difficulty straight away.
    I've set up the device, installed the drivers and Cubase LE4 that came with it. To begin with, the audio recordings were fine, they were audible and clear.
    A few weeks later and for a reason unknown to me, the recordings are really, really quiet. I've tried recording through audacity too but the problems remain the same.
    I'm using a Shure SM58 microphone but that isn't the problem because the recordings are now really quiet even using a guitar when they were fine a few weeks ago.
    Thanks in advance
  2. seife96

    seife96 Active Member

    If you are recording directly to windows 7 i can help you here!
    Go to controll panel-hardware and sound-sound.
    Select recording in the colum abouve the devices.
    select your device and click configure in the left hand corner.
    now choose "set up microphone"
    select other, press next and then just do your performance you want to record. after this your mic shood be louder.

    If not do this:
    Go to controll panel-hardware and sound-sound.
    Select recording in the colum abouve the devices.
    Choose properties and select levels in the colum.
    now you can optimate how loud you want it too be!
  3. Renate

    Renate Active Member

    I don't know how Windows 7 does any level control, but under XP there are no recording adjustments for the Lexicon Alpha.
    I find the input gain insufficient for a Shure SM58; you can't get near FS even screaming into the mic.
    Having such low levels makes using the mic for webcam/skype/live chat impossible.

    The limited choice of sampling rates (44.1 & 48) make specifying the Alpha as the default output device problematical.
    So you are left with using the normal PC audio as your default output to speakers.
    That means that the direct monitoring off the Alpha is useless.

    My next interface will have two microphone inputs instead of one mic, one instrument.
    Since my guitar actually has a balanced output it will be better than using a 1/4" unbalanced input.
  4. djmukilteo

    djmukilteo Well-Known Member

    What sort of monitors (speakers) are you using? Are you trying to use the internal PC soundcard with PC speakers?
    The Lambda is your soundcard and you should disable the internal one entirely. You should hookup speakers to the line outputs on the back of the Lambda using "powered" monitors or run the line outputs into a receiver/amp with speakers or if your PC speakers have there own 1/8" stereo input jack get an adapter (two 1/4" TS to one 1/8" stereo plug) and use that. Check the levels with a good set of headphones on the front of the Lambda and see if your output levels are correct!
    What sort of guitar do you have that has a balanced connector on it??
    Guitars and basses aren't balanced they are 1/4" instrument TS (unbalanced) unless your using a DI box. If that's the case the DI balanced connector should go to one of the the mic connectors on the back. Either way will work fine. There is an instrument input on the front of the Lambda specifically for plugging in a guitar or bass directly so really no need for a DI....you already have one built in!
    Last thing to know about the Lexicon products is they have terrible drivers!
    Do yourself a favor and get ASIO4all which is a free download and works far better than the Lexicon drivers!
    Lexicon also has problems with MIDI connections where the MIDI buffer overfills and then locks up and crashes the system.
  5. Renate

    Renate Active Member

    There are numerous ways to look at the levels that Lexicon Alpha is recording.
    Most recording software has some sort of meters.
    You can also record to a WAV file and look at the data.
    I have a utility that looks at the CCDF (complimentary cumulative distribution function) of the input.

    On the Lexicon Alpha, you can set the two input gain knobs at full and never even get in the neighborhood of clipping.
    On the output side, setting the output level above midway will cause analog clipping in the output stage of the Alpha.

    It's probably a subject for a whole separate thread why 80 full years after the invention
    of the electric guitar an unbalanced, high-impedance, low-level signal is still the standard.

    The Taylor ES and ES-T preamps inside their acoustic guitars put out a balanced signal on a 1/4" TRS jack.
    This is compatible with either a standard TS guitar cord or a TRS to XLR3 cable.

    Yes, the Lexicon drivers are not impressive.
    I've managed to get them to stutter horribly just playing YouTube back while monitoring the Alpha's input.
    I'll try the ASIO4All.
  6. BobbyRose23

    BobbyRose23 Active Member

    I have sort of the same problem, as I record my bass i cant never get it loud enough. the recording itself is at a low volume. It's like what the heck? It is never loud enough and it somehow clips!
  7. audiokid

    audiokid Staff

    My first thoughts are you are trying to push tooooooo low freq for the system to handle . You most likely need to HPF in order to get a better level. Do that and your ability to increase the volume of the bass will rise. Also, you may need to discover more about mixing your kick and bass etc. HPF is your best friend.
  8. BobbyRose23

    BobbyRose23 Active Member

    I may sound like an idiot, elaborate on what hpf is exactly? And maybe give it more of a low frequency after recording and in the mixing part... its for a friend so I am trying to get it done for him.... so take the bass out of my tone literally? lmao
  9. audiokid

    audiokid Staff

    I pretty much use one on every track. Adjust it until you start hearing it work and back it off just a bit and you are golden. But this is assuming you are also able to hear those freq via your monitors. If you want a kick ass bass, choose the instrument you want to be dominant and hpf the rest. Thats the basics for you and the secret to tight mixes.

    High Pass Filter

  10. BobbyRose23

    BobbyRose23 Active Member

    also recording my acoustic with no Mic since I do not have one, just plugging in, is it possible, cause I am right now and nothing is happening.... I am so darn confused haha....
  11. audiokid

    audiokid Staff

    Sorry, I wasn't understanding your interface and entire issue here. HPF has nothing to do with your problem. This is more to do with tracking or mixing including common issues that occur with reverb and excessive bass freq.
    When I saw lexicon, I thought reverb and processors.
  12. BobbyRose23

    BobbyRose23 Active Member

    I was using amplitude as far as anything on it.... besides that it was a normal track! And I fixed my acoustic issue, Battery was dead :D
  13. Renate

    Renate Active Member

    I've owned my Lexicon Alpha for a while now and I've made peace with it.

    One of the problems with a lot of ADC's is that they quote dB gain.
    The problem is, unless the input is a power (reference to an impedance) and the same for the output, you really can't speak of dB gain.
    You are inputting a power signal and outputting a numeric value.
    You should speak of "conversion ratio" or some such thing.

    If you really wanted to make things clear you would specify minimum and maximum dBmW for 0dBFS digital output.

    The Lexicon Alpha speaks of "50 dB gain" (IIRC).
    As noted, this is not a lot for a conversational tone into a dynamic mic.
    If you wanted to use the Alpha on Skype you might want another 20dB gain (which isn't there).
    But hopefully, you didn't buy an Alpha to use Skype!

    The best compromise here is to set the gain for no clipping (this might be full volume).
    Always record in 24 bit and compress/normalize in your mixing software.
    If you record in 16 bit and have to add 30dB of gain in post then you are really recording in 11 bit (16bit - 30dB/6dB/bit).
  14. Boswell

    Boswell Moderator Distinguished Member

    The Lexicon Alpha specification shows that the microphone input has a maximum voltage gain of 50dB with a maximum input level of -7dBu. Apart from not stating that the minimum gain is 0dB (or whatever), these units are completely consistent. It means that at maximum gain the peak input level (0dBFS) is -57dBu, which is just about enough for normal speaking directly into a dynamic mic like an SM58.

    Pre-amps of this type are voltage amplifiers and not power amplifiers, so there is no misunderstanding in saying that the gain (ratio of output voltage to input voltage) is 50dB. In order to relate this to absolute levels, you need to qualify the units, and hence the use of dBu (u = unterminated). This relates the level to 775mV, which is the voltage required to generate 1mW in 600 Ohm (0dBm).
  15. Renate

    Renate Active Member

    The difference between voltage level into reference impedance vs. absolute power is not the issue here.

    dB or dBu or dbmW only make sense if you are talking of the system from the input of the ADC to the output of the DAC.

    How many dBu is 0xffffff in 24 bit PCM recording?
    There is no answer to that.

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