Poweramp for Kemper and Kabinet.

  • I wired my zilla to run at 4 ohm's to get the full power of the bam ... 8 ohm might do it as well , 16 ohm probably when the input signal is hot ... I prefer not to push it to the limit !


    I must admit, I only use the bam together with a helix stomp as backup/rehearsal solution !


    Raf

    Kemper Powered Rack and remote/Mission pedal with Zilla 212 (K-100/V30) and Kemper stage with mission pedal

  • Understood, but the BAM is a bass amp at heart - not a Class D designed for this application or clean, neutral linear power. That said, if the OP likes it - it works. :)

    https://www.tcelectronic.com/product.html?modelCode=P0DI5

    Ultra-Compact 200 Watt Bass Head with Class-D Amp Technology


    BAM has a preamp optimised for bass with a Class D power amp. That is the only practical way to achieve such high power in such a compact design. No need for big power transformers etc.

  • Understood, but the BAM is a bass amp at heart - not a Class D designed for this application or clean, neutral linear power. That said, if the OP likes it - it works. :)

    I agree w/ dmatthews on staying clean even at the top for guitars. Here's why: A Class D amp (aka an H Bridge topology) works by turning the FETs completely on and off at varying pulse widths (time) to create a single note. The difference is that at lower bass frequencies vs guitar, more power is required to complete all the pulses required to create a single bass wave vs a guitar wave. This assumes both guitar and bass are running at the same SPL output. This same principle is used in switchmode power supplies. Imagine looking at an oscilloscope of a bass note vs a guitar note. The lower bass note is much wider vs a guitar. All the area underneath the wave is the amount of energy needed to create it. This explains why frequency = 1/time. The lower the frequency, the more time (and energy)) is needed to create the wave. hth

  • I agree w/ dmatthews on staying clean even at the top for guitars. Here's why: A Class D amp (aka an H Bridge topology) works by turning the FETs completely on and off at varying pulse widths (time) to create a single note. The difference is that at lower bass frequencies vs guitar, more power is required to complete all the pulses required to create a single bass wave vs a guitar wave. This assumes both guitar and bass are running at the same SPL output. This same principle is used in switchmode power supplies. Imagine looking at an oscilloscope of a bass note vs a guitar note. The lower bass note is much wider vs a guitar. All the area underneath the wave is the amount of energy needed to create it. This explains why frequency = 1/time. The lower the frequency, the more time (and energy)) is needed to create the wave. hth

    Add to that, CK himself pointed to the BAM200 as an amp to look at. And there are several here very happy with it.

  • Cool if the OP and others like the BAM Bass Amp.

    https://www.tcelectronic.com/product.html?modelCode=P0DI5

    Ultra-Compact 200 Watt Bass Head with Class-D Amp Technology


    BAM has a preamp optimised for bass with a Class D power amp. That is the only practical way to achieve such high power in such a compact design. No need for big power transformers etc.


    Is there a way to bypass the bass preamp (the separate tone stack and gain (distortion/drive) stage), to avoid the coloration it introduces?

    I understand how Class D works, and why it’s desirable for an application like the Kemper... but why throw a bass preamp and the extra coloration and circuitry into the signal chain?


    Why not just buy a good clean Class D amp? Like the ICE amps that Kemper uses? (They are readily available as power amps or modules)

    Serious question, not putting the BAM down.

    (I never used one, preferring a clean Class D power amp solution)

  • The BAM was mentioned by CK as an economical option to drive the Kone. A bunch of forum dwellers jumped on it and reported positive results. I guess TC is in the right position to push these units out onto the world market at an ecomical price.

    No option to bypass the preamp unfortunately (no FX loop) so people are setting the pre for as flat a response as possible - some tips on that here in the forum.


    As you say., other Class D options like the SD Powerstage units are more suitable on paper but more expensive for sure. The smaller ones (170/200 mono) run off an external power brick. The big kahuna - SD Powerstage 700 - is stereo but with a stereo volume pot so no adjustment of the gain on a per channel basis. They have useful tone controls and other features. The Icepower modules and the accessories necessary to use them are available but require some electonics skills for homebake use.

  • post deleted

  • SoManyGuitars, the ICE amp would still require a preamp. Although I agree bypassing the Bass eq in the BAM would be great but am not familiar with the amp and it may require opening it up and either bypassing the eq or changing the eq Rs and Cs. Probably not a good idea all around since it would invalidate the warranty and the bass eq is most likely using surface mounted components. Someone here on the forum although may have settings on the BAM that are acceptable for guitar work. hth

    For use with the kemper, you dont need a preamp, the icepower modules accept low voltage inputs no problem, as the kemper send from the main outs. Caveats from the modules is they are not set for receiving unbalanced connections on Bridged mode, so if you want that, you have to make an small board for conversion of unbalance to balanced (or simply use the balanced main outs from the kemper). Another caveat is you have to know a bit of electronics in general, specially if you want to use it bridged, put a tone stack for low/mid/treble control, or put a gain/volume pot into the amp. I made myself a 125ASX bridged poweramp, its nice and working now after a failed experiment I tried. So there I know what are we talking about.


    As to why not bypassing the bass eq, I had a look in the insides to the BAM, and the tonestack is not separated from the mainboard, and there are no schematics for it as it is a propietary design. It would take me a long time to decipher where the tone stack starts and where it ends,but I believe it is doable, and as far as I can tell, the power amp is pretty linear, its topology has nothing to do with it being a bass amp (actually I heard from the BAM first in a Jazz forum, where guitar players praised it for its clarity with hollowbody guitars for jazz performing, so there is that). I believe removing the tone stack altogether we will get a flat response, because of the nature of D amplifiers (as you mentioned), its switching characteristics are as linear as they get, just as switching power sources, no noise no nothing.

  • As I mentioned before, there should be a way. and I believe the result would be fairly transparent, it just turns out I am to busy and preffer playing than deciphering a PCB board. The thing with the BAM is, as I have shown before, its preamp (which pertains to the gain section), does nothing to the tone, it works as a secondary volume pot. It is a FET preamp, so it doesnt colour the sound until reaching clipping, but I did not see any change in frequency response on 3 o´clock position, so I believe the preamp is not designed for clipping, it is just more of a headroom control (as expected for a bass amp, but works wonders for the application).


    And by all means, the icepower modules are great, and inexpensive power/money ratio, thing is you either have technical knowledge and welding abilities, or you have to but a packaged thing, like the powerstage/BAM/Palmer/Harley benton modules. And from those, by far the cheapest is the HB, but not the most reliable. In my opinion, with the adjustments and everything, the BAM is the best bang for the buck.


    In comparision:


    Icepower 50ASX2BTL with no tone stack + unbalanced conversion (DIY) = 125-150 usd/euro to make (No case or fancy anything and you have to assenble it all)

    170 watt power at 4ohm


    TC electronics BAM200 adjusted to flat = 160-180 usd/euro (complete package, sturdy casing)

    200 watt power at 4ohm


    I say in those power leagues the BAM is a no-brainer. If you go louder, or stereo, then better an icepower 125ASX2 or 250ASX2(this one is pretty rare to get nowadays) like I did.

  • Yes, but the "preamp" is the Kemper, i use two of these Ice amps, works great

    digibob, good point, was focused on how to bypass the preamp w/o considering what was going to connect to it 8). fwiw, I used to design and build Class D pwr supplies but am not familiar w/ the pwr amps currently available. cheers

  • Finally got my Bam200 and I have to say it sounds amazing. I’ve always played through a L6 firehawk 1500 and a cerwin Vega cve-10 which sounded decent but playing through an actual cab sounds the best to me. Never been happier with my Kemper. Thanks for the input on the Bam200 everyone.

  • somebody took the effort to find the tonestack values for a flat EQ on thwe BAM200.

    Finally got my Bam200 and I have to say it sounds amazing. I’ve always played through a L6 firehawk 1500 and a cerwin Vega cve-10 which sounded decent but playing through an actual cab sounds the best to me. Never been happier with my Kemper. Thanks for the input on the Bam200 everyone.

    someone recently took the effort to find the tonestack values for a flat EQ on the BAM200. very helpful and useful im sure

  • somebody took the effort to find the tonestack values for a flat EQ on thwe BAM200.

    someone recently took the effort to find the tonestack values for a flat EQ on the BAM200. very helpful and useful im sure

    Alfahdj posted the linear settings, I never would have figured that out. Much thanks to Alfahdj for that.


    I picked up a fender supersonic 100 4x12 cab loaded with vintage 30’s for a steal. This cab, Kemper and the Bam200 is blowing my mind lol. I just want to play it all the time it sounds so good.

  • I was looking at the BAM200 at MF and read multiple reviews that complained it has no power and they doubt the 200W claim. They say it seems more like 30 or 40W and would only be good for maybe an acoustic gig. Would this be because they're going through higher ohm speakers maybe? Those that use it with the KONE seem pretty thrilled and I don't recall any power complaints. Is it adequate power for a large venue?

  • I was looking at the BAM200 at MF and read multiple reviews that complained it has no power and they doubt the 200W claim. They say it seems more like 30 or 40W and would only be good for maybe an acoustic gig. Would this be because they're going through higher ohm speakers maybe? Those that use it with the KONE seem pretty thrilled and I don't recall any power complaints. Is it adequate power for a large venue?

    i was using mine at home, dont think i pushed it past 9/10 o clock

  • I was looking at the BAM200 at MF and read multiple reviews that complained it has no power and they doubt the 200W claim. They say it seems more like 30 or 40W and would only be good for maybe an acoustic gig. Would this be because they're going through higher ohm speakers maybe? Those that use it with the KONE seem pretty thrilled and I don't recall any power complaints. Is it adequate power for a large venue?

    Volume really depends as much on speaker efficiency as power output. The Kone speaker is about 98dB efficient if the comparable Celestion is anything to go by. A pair would be 101 dB at one watt and 4 would be 104 dB at 1 watt. So you would have to wonder what cabs bass players were driving with it and what amps they were comparing it with.


    The other salient point: the way human hearing works (see Fletcher Munson curve) - bass frequencies need heaps more power to generate the same perceived volume levels as mid frequencies. Mid range guitar signals are right in the zone where the sensitivity peaks for human hearing so we hear guitars loud and clear with modest amp power. 1000 watt bass amps are commonplace, a 100 watt Plexi can - if I might borrow a phrase from Spinal Tap - make your eardrums bleed.