Harley Benton GPA-400

19 "Guitar Power Amplifier

  • Lightweight Class-D technology with switch-mode power supply
  • 2x 200 W @ 4 Ohm
  • 2x 100 W @ 8 Ohm
  • 2x 50 W @ 16 Ohm
  • Bridged 400 W @ 8 Ohm and 200 W @ 16 Ohm
  • Frequency range: 20 Hz - 20 kHz
  • Input sensitivity: 335 mV
  • Damping factor: > 80
  • Signal- noise ratio: > 90 dB
  • Total harmonic distortion (thd): < 0.15%
  • Power consumption: 18 W (standby current)
  • Dimensions (W x D x H): 482 x 250 x 44 mm
  • Format: 19"/ 1 HE
  • Weight: 3 kg

These are other customers' choices:

Customers who looked at this item have bought these:

Harley Benton GPA-400
65% bought this exact product
Harley Benton GPA-400
Available immediately
Available immediately

This item is in stock and can be dispatched immediately.

Standard Delivery Times
185 € Add to Basket
Palmer Macht 402
13% bought Palmer Macht 402 269 €
Seymour Duncan Power Stage 170
4% bought Seymour Duncan Power Stage 170 379 €
Mooer Baby Bomb 30 W
4% bought Mooer Baby Bomb 30 W 95 €
Harley Benton Custom Line Thunder 99
4% bought Harley Benton Custom Line Thunder 99 95 €
Our most popular Electric Guitar Power Amps
129 Customer Ratings:
  • 5
  • 4
  • 3
  • 2
  • 1
4.7 / 5.0
  • handling
  • features
  • sound
  • quality
97 written ratings Read all reviews
Great Power Amp If You Have a Good Front End :)
Angelus502, 30.06.2015
I was a bit hesitant about buying this, Class D, very inexpensive :S But Im glad I did...

Where to start.. Class D amps.. So amp's come in basically 3 types, Tube, Solid State, and Class D. Tube amps have that nice warm tone and gorgeous sounding harmonic distortion, breakup and compression, plus there loud for the watts, but unfortunately cost a fortune. Solid State amps tend to just have raw power and balls once you get up there in the watts, but sound a bit sterile compared to tubes. Class D or digital amps always sound incredibly detailed but cold and sterile to my ears, they tend to put out what you put in without warming anything up or rounding off the bad edges. Also 200 Watts Class D is volume wise about the same as a 30-50 watt tube amp. But as this was for a second guitar rig using some preamps, a G Major FX and a Harley Benton 2x12 Vintage Cab I already owned I didn't want to be shelling out $600-$1000+ on a tube amp, well not at the moment.

Initially I had some problems dialing in a good tone, I think the amp probably needed some run in time to take out a little new amp harshness, and while it didnt sound like a cheap $200 combo when I had a solid state preamp hooked up it, it wasn't doing it for me it tone wise. Solid State preamp and Class D power amp, probably not a good way to go :(

Next up I hooked up a 20 year old Digitech tube preamp, with a bit of EQ tweaking and a OCD clone as a boost I was happily rocking out thinking this sounds pretty good.

Then 2 days ago the AMT SS-10 I ordered turned up. OMG, chimey cleans, gorgeous slight blues breakup, and the crunch / high gain have a great tube compression, and it sounds almost as if there's some power tube breakup and sag going on in the tone. I was in guitar nirvana gurning away like an idiot. After I finished playing Van Halen's "Panama" solo I thought "damn my playing doesn't usually sound that good".

So there you go.. Class D... **** in = **** out, great tone in will equal great tone out. Very transparent and it's not going to hide or warm anything up.

A couple of other things...

* I did A/B it against a blackstar HT5 power stage a few weeks back and the HT5 sounded flat and muddy in comparison.
* It's not hugely loud. I dont know if it would run stereo 4x12 cabs at gig volume, but in bridged mode it should be fine for a single 4x12.
* What's with the dodgy cheap knobs Thomann? It feels like they are glued on too :(
* The tone pot values are a bit too sensitive as well, 10 to 2 o'clock is about all that's usable.
* If you're thinking about getting one of these.. I did try running the 2x12 cab in stereo , but I was getting some weird phase cancellation, probably due to stereo FX.
* Very light.
* Runs cold.
* If you have a high end ( or new model ) modeler this would probably work very well to, unfortunately I don't have any good modeling gear anymore to test with.

I was planing on replacing this with a 20 Watt tube amp when I had the cash, but if my feelings about the ATM don't change, and I don't end up putting the AMT in my main rig, I don't think I'll bother... Great inexpensive power amp if you have a good front end \m/
Helpful · Not helpful · Report
Report rating…

Do you believe this rating to be inaccurate or unacceptable for some reason?

Send report
A fantastic amp that can compete with the bigger name Amps!
Gerard1742, 01.03.2016
I got this amp based on a gut feeling I had, and also the postive reviews it has received here on this website. Also look at the sales of this amp, it is proving popular.

I have moved over to using rack equipment in the last year and I wanted to buy a new power amp. I was considering going for a plain old clean power amp used for general sound applications. I then stumbled upon a few power amps designed specifically for guitar. The Rocktron Velocity was one. That lead me to this site, which then introduced me to the Harley Benton GPA-400. Immediately what appealed to me was the 100watts more than the Rocktron and also the cheaper price!!! Before I bought the amp I had contacted Thomann pre release of the amp. One of their technicians told me the amp was designed to compete with the likes of the Velocity amp. This got me very curious indeed. Also very excited. It wasn't until a year later however that I actually got to buy the amp and try it for myself.

Before I got a chance to buy this amp I noticed it had been selling well. In fact it's currently 81% of peoples choice of guitar power amp from this website. So I guess you could say it's popular.

Ok so I got the amp, within a matter of minutes I had it set up to run 4 speakers cabs. Four 2x12" cabs easily connected to the GPA-400. It has 4 speaker outputs! This great. It makes it more flexible. Each channel (A and B on the amp or Left and Right to me and you) has 2 speaker outputs each. If you connect a speaker cab to each of the speaker outputs on one channel you get a parallel speaker load of the two cabs. In my case I had 2 cabs at 16ohms, this in parallel worked out as 8ohms. So this was the same for both channels meaning I had 8ohms load in channel A and 8 ohms load in channel B. This then means the GPA-400 is able to run at 200watts output. Ok so 200watts was my output and now I had to see if that was loud enough for my band. Yes it was!!! I found I had to set the knobs at 2or 3 o clock on each channels volume control in order to be loud enough. This meant that I still had more to travel with each volume control and that means if I needed even more volume, I had there on tap should it be required.

Well it was not required I am happy to say but is good to know you have head room. I have to also mention that had I been running the amp at 4ohms each side I would have had a total of 400watts output as opposed to the 200watts I was using, so this means the GPA-400 is capable of even more volume!!! Good to know these things.

As I was testing the amp I had the "Resonance" and "Presence" controls centred. They have an indent to find the centre so I am assuming that centre is 0 and left is - value and right is + value. I began with both controls centred as I say, and after a while I added in a little presence to give a tiny bit more Hi end to my sound. What is really good about these controls is that you can centre them before every gig and then say you need a bit more bass, you can adjust to taste depending on each venue you play. The same goes for the presence control. These controls are independent to each channel so you might want to run channel A a little brighter than channel B to help with stereo seperation or just to suit taste. It's really nice little features to have. These controls are controls that appear on the Roctron Velocity also and I'm assume they function similarly from what I have read. Both controls centred in my opinion sounded really good, not harsh, not brittle and dare I say warm sounding. I added a little presence each side purely to give a bit more cut through with my guitar sound.

I ran the GPA-400 using an ADA MP1 preamp placed in the FX loop of a Boss GT5. To me this combination sounded excellent. The GPA-400 really give my rig the power to get heard. It also complimented it somewhat. I made zero adjustments to my rig itself. I basically dialed in the little bit of presence on the amp and that was it! It could not have went any easier.

Looks of the GPA-400 are nice. It's simple and smart looking. It is also sturdy and pretty light! 2.5kg! It really is well made. The jacks all feel good quality and everything is nice and solid feeling to plug into. There are nice little led's at the front that can detect the signal coming into each channel. Nice little useful feature. There is also a peak light if say you were over loading. I couldn't test it to see if that worked because I guess I wasn't over loading and I didn't feel it was necessary to try to.

The only thing (and it's so minor I don't really need to mention it) is the control knobs feel cheap and are not to my taste. I rectified this by buying my own black and silver knobs to swap them out with. Just my own taste. One other minor issue I have just recalled is that I don't like that on the back of the amp Channel B is on the Right hand side and Channel A is on the left hand side. Why do I not like this? Because when you go back around to the front of the amp and you turn up the channel A volume or anything else on Channel A this is on the left hand side, but controls the speakers on the right hand side. In fairness I can see how this design flaw happened but it is a little bit annoying but seriously not important. My work around this was to swap the speakers on the right hand side into the left channel and left hand side speakers into the right channel, this means from the front of the amp the controls for each channel correspond with the speakers on the same side. Makes sense right?

Think I've covered everything. In short this amp is cheap, it's well made, it looks decent apart from the knobs, it's very powerful, it doesn't heat up much after several hours of use, it's light, it's cheap (of did I say that again?), it's very loud, has lots of head room and it also sounds great and feels great unlike some brittle sounding sterile PA amps. I would buy another if this one broke. In fact I may well do for a backup. I really do recommend this amp, I think it's a real gem and it's great Thomann are selling something of this quality for such a reasonable cost.
Helpful · Not helpful · Report
Report rating…

Do you believe this rating to be inaccurate or unacceptable for some reason?

Send report
185 €
Including VAT; Excluding 20 € shipping
Available immediately
Available immediately

This item is in stock and can be dispatched immediately.

Standard Delivery Times
Share This Product
Your Contacts
Phone: +49-9546-9223-20
FAX: +49-9546-9223-24
Online Guides
Guitar Amps
Guitar Amps
The following pages give an overview of the various types of guitar amp available.
test results:
Offers include 24% Greek VAT and are valid as long as stocks last. Shipping costs to Greece are 20 EUR, free shipping on orders above 298 EUR. Please click here for international Shipping rates. We do not accept liability for typographical errors or inaccurate information of any kind. *RRP = manufacturer's / distributor's recommended retail price in Germany
Recently Viewed
Shure SE215-CK

Dynamic sound-isolating in-ear earphones Special edition exclusively available from Thomann, Dynamic micro-driver, Shields over 90% of ambient noise, Suitable for in-ear monitoring as well as HiFi listener for e.g. MP3 player, Ear-insertion, Impedance: 20 Ohm, Sensitivity: 107 dB SPL/mW,...

Recently Viewed
Yamaha Stagepas 1k

Yamaha Stagepas 1k, portable active PA system, 1000W (HF:190W+LF:810W) power output, 12" subwoofer for low frequency, 1.5" x10 slim line array speaker for high frequency, digital mixer (3 mono mic/line + 1 stereo line), multi band comp mode for master...

Recently Viewed
Electro Harmonix BASS9 Bass Machine

Effects pedal for electric guitar Generates different bass sounds from the instrument signal, No special pickups necessary, With a new algorithm that has been revised for transposing one to two octaves down with superior dynamics and optimised tracking, 9...

Recently Viewed
Sennheiser HD-600 New Version 2019

Headphones Vibrant, Open, Circumaural, Impedance: 300 Ohm, Sound pressure level: 97 dB, Transmission range: 12 - 39,000 Hz, Two-sided cable routing, 3 m Cable with 3.5 mm jack connection, Weight without cable: 253 g, Weight with cable: 309 g,...

Recently Viewed
XVive U3C Microphone Wireless System

Digital wireless microphone transceiver system For use with condenser microphones, Integrated phantom power: 48 V / 12 V, Works without battery or mains power, Integrated rechargeable lithium rechargeable battery, Range up to 20 m / 70 ft. (without obstacles),...

Recently Viewed
Roland DJ-707M

Roland DJ-707M; DJ-Controller; 4-channel Serato DJ Pro controller with 4 decks; combines a portable live sound audio mixer, loudspeaker management system and performance DJ controller; built-in 24-bit/48 kHz audio interface; 4-band output EQ, multiband compressor and limiter on each Master,...

Recently Viewed
Polyend Poly 2

Polyend Poly 2; MIDI to CV interface; supports all Midi USB controllers with class compliance; USB Type B port for direct connection to computer/DAW; four gate & pitch outputs; first, next & channel mode; twelve configurable CV outputs; scales function;...

Recently Viewed
Stairville BEL1 Battery Event Light 15W

Battery-Powered RGBAW LED Spotlight Flexible spotlight with integrated battery for ambient lighting, Beautifully subdued housing makes possible an unobtrusive set-up, High light output and vivid colour rendering ensure an impressive ambience, Battery operation and the intuitive menu enable a...

Recently Viewed
Marshall Kilburn II Black

Portable Bluetooth Speaker Loudspeaker equipment: 20 W Woofer and 2 x 8 W tweeter, Class D power amplifier, Frequency range: 52 - 20,000 Hz, Bluetooth Standard V 5.0, Input: 3.5 mm Mini jack for MP3 player etc., Volume control....

Recently Viewed
KMA Audio Machines Logan Overdrive

Effect Pedal for Electric Guitar & Bass Open and very touch-responsive, High-headroom-design (up to 25 dB)solos, Perfect for use as a preamplifier with IR Cab-Sim or amp-less, 3-band Active EQ with adjustable middle frequency, Middle footswitch to boost solos,...

Recently Viewed
Sequenz Volca Rack

Synthesizer Rack Offers enough room for up to 4 Korg Volcas, Sturdy aluminium frame, Rubber legs for a secure hold, Side panels are made from wood, Asymmetrical side panels enable 2 different kinds of installation, Dimensions: 411 x 242...

Recently Viewed
Stairville BEL1+ Battery Event Light 15W

Battery-Powered RGBAW LED Spotlight Flexible spotlight for ambient lighting, with integrated battery and wireless DMX, Beautifully subdued housing makes possible an unobtrusive set-up, High light output and vivid colour rendering ensure an impressive ambience, Battery operation and a cableless...

Give Feedback
Feedback Found an error or want to give us feedback about this page?

We're looking forward to hearing from you and aim to solve any problems as soon as we can.