Your browser is out-of-date!

Update your browser to view this website correctly. Update my browser now


Labgruppen fP6400 Sound Reinforcement Amplifier

You say you need a lightweight, yet powerful sound reinforcement amplifier. In a market filled with lightweight, switching power supply amplifiers Lab.gruppen enters with its top-of-the-line fP6400 ($4,495).

You say you need a lightweight, yet powerful sound reinforcement amplifier. In a market filled with lightweight, switching power supply amplifiers Lab.gruppen enters with its top-of-the-line fP6400 ($4,495). Yes, from the country that brought us Ikea with its weird names for furniture, comes an amp that is setting the touring world on its listening ear.
Product PointsApplications: Live sound, touring, install, and club

Key Features: Two-channel; 3,200m watts per channel, switching mode power supply, clip limiter, parallel, link

Price: $4,495

Contact: Lab.gruppen at 805-373-1828, Web Site.

B>Review Setup: Yamaha PM 3500 console; dbx Drive Rack 480 processor; EAW SB 850, SB250 subwoofers, KF 730 speakers.

First thing you will notice when you pull this monster of an amp out of the box is how light it actually is. Weighing in at an astoundingly low 22 pounds, you feel as though the factory just sent an empty chassis. Once you fire up the amp, you will know it’s definitely not empty.

The fP6400 claimed output is 3,200 watts per channel into two channels at 2 ohms. Inputs include two Neutrik combo connectors accepting XLR or 1/4-inch TRS jacks. There is also a parallel link jack, and link switch for combining inputs to both channels or out to another amp. Outputs are set to two Neutrik, four-pole, Speakon connectors – one for each channel, either of which would provide an output connection when set up in bridged mode.

On the input side, Lab.gruppen designed a flexible gain structure to meet the needs of different systems. This is done by a multiple position gain DIP switch on the rear panel. The maximum amplifier gain can be set to all industry standards: 20 dB, 23 dB, 26 dB, 29 dB, 32 dB, 35dB, 38 dB and 41dB. The fP6400 also has a matching load select switch (MLS) for converting output power requirements, depending upon the load driven and therefore managing the current through the power supply. The switch can be set to 0, -2 dB, -4 dB or -5 dB. A clip limiter is also incorporated in the design that is switchable, on and off, for both channels.

The front panel contains the gain controls for both channels via 31-position detent knobs. From there you move to the “Christmas Tree” of LEDs.


I had the pleasure of using the fP6400 on several shows over the last few months. First was a government dinner gala. The fP6400 powered a set of EAW 250 subs. Head room was fantastic; I was very impressed. The link switch is a very handy feature, because, if you are like me and run subs in a mono configuration, the single input to both channels is important. The “Christmas Tree” is impressive and is fairly accurate in letting you know not only the available headroom you have left in the amp, but how hard the amp is really working.On the negative side, with so many LEDs placed so close together, sometimes it is hard to read an exact level. With the multiple gain settings you can configure the fP6400 to be as efficient amp as you will ever need.

I also used the fP6400 on a live show by the 80s band, The Smithereens. I was using an EAW 850 rig with two double 18-inch cabinets per side for subs. Since the cabinets were 4 ohms each I thought I would parallel them and run the load down to 2 ohms per channel of the fP6400. Wow! was my only reaction.

I have never seen or heard a set of 18-inch subs work so efficiently. The band was thrilled by the output considering it was a 2/1 configuration of low, mid, high cabinets over subs. They normally request a 1/1 ratio. Throughout the night, I ran the fP6400 hard for over five hours, and though some engineers would not recommend the low 2-ohm configuration, the amp had no problems keeping up. No failure or over-temperature (thermal) as you might see with some other conventional style amps. I think the DJ, who was playing after the band, was happier than anyone. All of his dance grooves had power behind the low end and in return the people flocked to the dance floor.

The last test for the Lab.gruppen was to fire it up in the shop. I thought I would test it by powering the new 730 small line-array from EAW. In this fashion, one channel powered the lows and one would power the mid/highs of this biamp cabinet. Driving four 730s at an 8-ohm rating would give me a good feel on the real versatility of the fP6400.

Once the gain structure was set correctly between the console output and the processor settings the 730s came alive. Remarkably the fP6400 preformed with the same grace and smoothness that I heard during my other shows.


In this ever-changing market it is a refreshing change to see a company really get it right. There is a reason this amp has made so much noise in the industry; it exceeded every expectation. If your needs require a powerful amp that can take the abuse of touring, the Lab.gruppen fP6400 should be on your list. It impressed me to the point that I think it’s time to rework our amp racks with some Lab.gruppens.