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189,819 posts
  • JSA
    Contributor - Level 1
    0 95
  • Johnnyangel
    Contributor - Level 1

    what a lot of BS to get in here, trying to get to someone to ask whether I can buy an amplifer for my powered speaker (amplifier only already got power supply heat sink speaker and controls) don't want to buy a complete powered speaker box, any ideas 

    0 112
  • Gasper
    Contributor - Level 1



    I am new here. I would like to ask some technical question about new Lab Gruppen PDX3000 amp. It seems to be a perfect solution for my JBL4645Cs. First of all I would like to know what is the DAMPING FACTOR (aprox. up to 300Hz)?. For the input on XLRs I would like to connect it directly from the integrated amplifier from speaker terminal (high level to low level); I made some measurements and normally high level does not exceed 0,5V - how much volts can take XLR input on PDX3000?


    Thank you very much in advance.


    Kind regards,


    Gasper Jancigaj

    0 424
    • Gasper

      Hi Gasper,


      The following is a white paper published by Lab.gruppen detailing why we do not use Damping Factor in our specifications.


      Damping factor

      The damping factor is determined by the quotient of the speaker impedance and the output impedanceof the amplifier. To state the damping factor figure of an amplifier is meaningless, as the speakerimpedance’s varies with the frequency and the various types and brands of loudspeakers existing.The figures of the true damping factor are only valid for a specific amplifier/ loudspeakercombination. This fact gives one of the reasons why Lab.gruppen don’t publishes the damping factorfigures.The only figures that are relevant for amplifiers are the output Impedance figures. Most amplifiers onthe market only show low output impedance (or high damping factor) at low frequencies and high(er)at high frequencies. This is due to the improper design of the output network and/or frequencydependent feedback. Lab.gruppen design has the feature to have nearly constant impedance over theaudio frequency band with a value of 0.05 to 0.07 ohms (50-70 mohms) . This causes less coloration.Another feature of the power supply in the fP 2200 - fP 6400 (thanks to the stabilised power supply),is that the output impedance doesn't rise during clip situations. In most conventional amplifiers theimpedance rise 10 or l00 times during clip. That causes uncontrolled movements of the speaker-cone.The conclusion must be that the Lab.gruppen switch mode power supplies sound better or have betterdefinition, especially in the bass region, compared to conventional designs.


      Damping factor influences on active and passive frequency divided loudspeakers

      Another reason not to publish the damping factor is that it’s not relevant to the audio quality of the power amplifier. For example; a professional loudspeaker driver has a DC-resistance between 2 and 5ohms, which is connected in series with the driver in the equivalent circuit diagram of the driver. Inthis case, the damping factor has more to do with the speaker itself than the amplifier, as the speakerdriver is connected directly to the power amplifier just as in an actively divided system (see example below).In a passively divided speaker system the filter network circuit are placed between the power amplifierand the speaker driver. In this case, however, the filter impedance determines the damping factor ofthe speaker driver. The output impedance of the power amplifier can influence the characteristics ofthe filter response, but it’s not sure that a lower impedance (higher damping factor of the poweramplifier) will give a better response. A classical example is the tube amplifier, which has relativelyhigh output impedance and which gives a very good sonic result in most cases.





      I am not entirely sure I understand your question,  "For the input on XLRs I would like to connect it directly from the integrated amplifier from speaker terminal". Could you explain what you wish to do in a bit more detail please?


      The PDX inputs are Line Level, if you are using an appropriate audio source then it will be a line level output also. What are you planning on using to drive the input on the amplifier?

      • April 6, 2020
    • Gasper
      MrPaulDavidThomas I'd like to know how you get on with your JBL 4645C's. Alas the answer you got didn't really help as far as I can see :-(
      • December 7, 2021
  • sowatt
    Contributor - Level 1

    is there any other way to get spare parts of the PLM series 
    bequase every time we if send it to repair and they have this Absurd high repair costs
     we can also do it ourselfs   its not that hard   its more hard to find the problem  
    but with 7 plm's in total  we rather want to do it ourselfs 

    0 163
    • sowatt

      Hi Sowatt,

      You can contact our CARE team and ask but I would warn you that performing these repairs yourself will void your warranty. Also, our service centers have specialised repair and testing equipment which is quite essential to perform a quality and most importantly, safe, repair.

      Not trying to downplay your skills as a repair engineer, just a bit of insight into what goes into the process of service.

      Honestly I would very strongly reccomend you send your amps for repair in a certified service center, if you are getting repeat failures then its worth doing some analysis as to the cause also. It may be that you can avoid having to send it in to start with.


      I am more than happy to advise and assist further...


      • April 6, 2020
  • BlackBarnBar
    Contributor - Level 1

    Warenty lab 2000? I want send my lab 2000 in for repair. How and wher do I send it? 

    0 166
    • BlackBarnBar


      Hello Rickard, welcome to the community.


      I suggest that you raise a Care ticket (Service Request) explaining your problem. This is done by clicking on Support at the top of the page and then clicking the Create a Care Ticket button. This is only possible if you have completed the required fields in your profile. The Care ticket is currently the only way to request technical support, service and spare parts from any of the Music Tribe companies.

      • January 29, 2020
  • Hackerstown
    Contributor - Level 1

    Anyone have any input on Boss Katana MKII ?

    0 126
  • Pavel-Cerny
    Contributor - Level 1


         Now I'm install MacOsX Catalina - impossible to used with IntelliDrive for my 6x IPD2400, is big problem for me. Please inform us when will ready for Catalina - your last update was in 2017, is time for next upgrade.

    Thanks, Pavel

    0 284
  • Kurtis0c1995
    Contributor - Level 1

    Had the nx4-6000 for 8 months now and has been fantastic up until a week ago. Just tripped the sockets and stopped working. Everytime I plug it in now it just trips the socket. Help

    0 146
  • philotbeddo
    Contributor - Level 1
    Behringer Europort PPA2000BT Portable PA System with Bluetooth
    For the past couple of months is randomly clips out the right side for a second or two at a time.  I can't find any excessive sound source or reason for which it would be doing this.  It also randomly starts making a super loud white noise static sound.  I have to turn it off and turn it back on to make it go away.  Super annoying when in the middle of a song or gig.
    0 121
  • Markybehr
    Contributor - Level 1

    I recently bought a Ampeg fridge bass cab with a single 1/4” input jack. Searched for an amp to pair with it—found the BX2000H. This amp has two Speakon outs, though, and I’m wondering what the correct way is to deliver all of that beefy wattage to the 8x10 cabinet. Ideas?  Thx

    0 117
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