KPA with D-Class Amp Modules

  • Has anybody tried using the KPA with the new class D amps out there? I am talking the ICE amp or the NCore modules from Hypex. These are class D amps or modules which occupy very little space, highly efficient, and don't need a heatsink! They are good enough for high-end audio now, and are relatively inexpensive to DIY. It would be cool to see if you could put one into the KPA as there is plenty of space for it. I've seen some old preamp racks modded with these new modules so it makes it into a full-fledged power amp as well ... with almost no extra weight or heatsink needed. Idle power is also stunningly low for some of these modules (5W) though they can pump out hundreds of watts. Some modules have two amps to support stereo operation.


    http://www.icepower.bang-olufsen.com/
    http://www.hypex.nl/


    I am thinking of getting a separate stereo unit and using that as a power amp. Would be a cool little setup with the KPA.

  • You can get the ICE amp module 125ASX2 (125W/ch into 4 ohms) for $200. Or a stereo amp (mainly used for hi-fi) for $800 in a nice chassis. Or maybe the ICEpower 1000ASP which is 550W into 8 ohms. and is only 23.2cm wide x 15cm deep:


    http://www.icepower.bang-olufs…utions/speaker/ASP_SERIES


    That is less power than the KPA head @600W into 8 ohms, but pretty good performance spec wise. I would be curious what is the THD and freq specs for the KPA amp. Does anybody know?

  • Interesting, somewhere I read the power amp in the KPA is from bang&olufsen (don't know if it's true though) - maybe something similar like this icepower stuff?

    MJT Strats / PRS Guitars / Many DIY Guitars -- Kemper Profiler Rack / Kemper Remote / InEar

  • 250ASX2 looks promising (630W into 8 Ohms). Think I'll try that one out, 220€ + custom plate for mounting in the toasters hole should be around 20-30€ + some jacks.... sounds nice. I'll report back.

    MJT Strats / PRS Guitars / Many DIY Guitars -- Kemper Profiler Rack / Kemper Remote / InEar

  • Awesome that the KPA power amp is using ICEpower modules. These things are simply amazing. I have an old guitar solid-state stereo preamp that has been modded to have an ICEpower 125ASX2 module (also running in stereo), so it's now a power amp also. It is running into a stereo 2x12 cab, and the sound is awesome. The bass response on these new class-D amps is stunning. Yes, THD goes to 10% at only the very high-end of the range, but my cab won't ever get that much power. Plus, the THD from the speaker will probably be much greater and affect the sound long before you hit the limit of the power amp.


    The NCore modules from Hypex also look really cool, and you can buy the N400 modules as DIY only. But you then need to get the PS. The 125ASX2 is completely self-contained. Some people have mentioned that the Hypex modules sound better. Specs do look comparable, but I think the ICEpower stuff is cheaper since they actually have a custom-designed ASIC in there for some of their functions. The Hypex guys seem to like discrete stuff, and are really expert analog guys.


    Either way, you can't go wrong.

  • Cool, just got a 250ASX2 from eBay for 200€. I'll have some laser cutted bezel (anyone else interested? as 10 pieces are usually as expensice as 1 ;( )- should fit the back hole.

    MJT Strats / PRS Guitars / Many DIY Guitars -- Kemper Profiler Rack / Kemper Remote / InEar

  • Awesome that the KPA power amp is using ICEpower modules. These things are simply amazing. I have an old guitar solid-state stereo preamp that has been modded to have an ICEpower 125ASX2 module (also running in stereo), so it's now a power amp also. It is running into a stereo 2x12 cab, and the sound is awesome. The bass response on these new class-D amps is stunning.

    Today we were testing the KPA poweramp in a music store through a Marshall 2x12.
    No one could believe the bass response they were hearing through the cab, it was simply unbelievable.
    In fact, a few of the guitarists in the store said to me that even with my non stop 'salesmanship' and hyping over the last 18 months they were still not convinced about the KPA...but today they stood there stunned, they couldn't believe what they were hearing coming out the cab, they admitted that the KPA is unbelievable. :thumbup:

  • Anybody who is going to do a DIY and add an ICEpower module (either 125ASX2 or 250ASX2), let us know how it goes. For example, will you run them in bridged mode (mono) for a 600W amp like KPA does, or will you run it as a stereo unit? Also, what points will you use as the inputs to the ICE modules? I have read that these modules like to be driven by a low-impedance. I am assuming these points need to be chosen carefully so as to maximize the signal path to the power units while not loading the preamp outs.

  • Today we were testing the KPA poweramp in a music store through a Marshall 2x12.
    No one could believe the bass response they were hearing through the cab, it was simply unbelievable.
    In fact, a few of the guitarists in the store said to me that even with my non stop 'salesmanship' and hyping over the last 18 months they were still not convinced about the KPA...but today they stood there stunned, they couldn't believe what they were hearing coming out the cab, they admitted that the KPA is unbelievable. :thumbup:

    The test made with cabinet sim off or on?