Loads of Power, Loads of experience...


Knowledge base

Our knowledge base has been created at the request of  some users. The idea is to answer some of the most common questions we get. There is a now a download link on the navigation bar that tackles some general amplifier theory and the rational behind Lab.gruppen's design.

What's the difference between the Lab1200 and Lab 1200C?
The Lab 1200 is basically two Lab 500s in a 2U box. There were only 4 or 5 of these sold in the UK. The 1200C came about as the result of some crude experimentation at Network PAD and the inspiration of Tim Boyle at Concert Sound. The resultant product, designed by Kenneth Andersson was a modification of the existing Lab 1200/1300 but with more than twice the output power. This was achieved by using a new protection circuit called ALS. Plastic drive devices and the inclusion of an optically isolated MLS feature completed this upgrade. The latest version of this product is the fP2400Q and for those of you who read specs, you'll notice that the Lab 1600 and subsequently the fP2600 shared the same platform. In fact all current Lab Gruppen Class AB amplifiers now share this platform but only the RSMPS units have the optically isolated MLS feature.

Which Lab.gruppen amps have a class AB output stage?
All iP prefixed amps bar the 450.
All fP prefixed amps bar the 3400 and 6400.
All Lab prefixed amps bar the 2000,2002,2000C,4000 and 300.

I have a Lab.gruppen SPL-2/2B/3 that's faulty where can I get it fixed?
Being the total Lab.gruppen service provider we can repair all Lab.gruppen products including the ACN-, SPL- and give technical advice on DSP signal processors.

There's no sound coming out my subs but the meters are working!?
If the meters are working then the amplifier is working. The most probable cause is that the Speakon connector is not twist-locked. Even after 15 years this is still a commonly reported fault!

What's the difference between an fP and fP+ amplifier?
The FP+/C-series is a totally new platform designed by Lab.gruppen. Kenneth Andersson started work on this platform more than 10 years ago but could not realize it because the components needed had not been commercially developed yet. The advantages the FP+ platform has over the fP amplifiers are far too numerous to detail in this knowledge base but, the bullets are:-

  • Higher power density.
  • Four high powered amps in 2 rack spaces without the ridiculous depth.
  • Fewer component count.
  • A totally new PSU .
  • An upgrade on the Class TD output - more efficiency is achieved.
  • Computer monitoring as standard.
  • All these amplifiers are Class TD except those ending with an “x” (series x) which are pure Class D.


I notice that the fP amplifiers have removable filters on the front panel. Can I have these on my 1st generation Lab amps?
Yes you can, the filters are retro-fittable to existing lightweight amplifiers. You have to remove the existing filters from behind the front panel- something best done by us. One of the ingenious approaches made by the original design team was to make those who bought into the dream early not feel left out when new products were developed. Therefore the look of a Lab 2000C is not too dissimilar to that of a fP3400.

What is “verification”?
Verification of an amplifier's specifications mean that it achieves as near as possible the original intended performance. Some service houses just make sure a repaired amplifier produces the watts! Invariably, checks for items such as crosstalk can indicate internal wiring faults. Residual noise can point to connectors that need replacing...the list goes on.

When Lab.gruppen started to build amplifiers the one thing they wanted from their designs was longevity. There is no reason why any of their amplifier designs should not give a working life of more than 20 years. However, this can only be achieved with the correct maintenance schedule. We can instigate the required schedule because we have the correct attitude to maintenance. See our philosophy page. All AAS verified Labs are accompanied with all relevant graphs and printouts for any Lab.gruppen amplifier.

I have some 1st generation Lab amps and want to move them on without having to sell them at a stupid price, how should I go about it?
There are different ways to move your amps on.

  • Lab Gruppen have introduced the Lab gruppen Certified Pre-Owned Program(LCPO). Basically, when you purchase new fP+ or C series amplifier(s) they undertake to advertise your old amplifiers s on the LCPO web-site, in addition to offering a 3-year warranty. The program only covers amplifiers that are less than 10 years old, therefore amplifiers such as the SS1300, Lab2000 and Lab 500 are not covered. It only covers upgrades to Lab.gruppen amplifiers.

As with all schemes there's no guarantee that any of the above will yield the results you want. One thing to check is the “street price” of the equivalent Lab you want to sell, not the published list price.