Icepower 1000A Bandwidth

  • Hopefully this post will not upset too many Power Head fans, but I would like to post my observations about the Power Head with the Icepower 1000A amplifier (and the Power Rack as well I assume, since they use the same power amplifier) .


    I purchased my first KPA, a Power Head toaster model (as an Xmas present to myself) back in Dec 2013. My intention was to use it as a standalone amplifier to drive a cab and eliminate my pedalboard and boat-anchor tube amp. Since I bought it, I have had many comments from fellow bandmates (in the bands I have been in or am in) regarding how dark the sound was from the cab, no high end. Going through the main out direct to the PA sounded nice and sparkly all the time, but the cab sound was dark no matter what I did. I was using a Weber Vintage speaker at the time in an old Lopoline 1X12 convertible cab, as well as some Carvin 2X12 cabs.


    I figured the issue was the speaker. I went to a Beyma 12GA50 in my little ol' Lopoline 1X12 cab, no difference. Then I bought a Mission Engineering Gemini 1-P passive FRFR cab, but still no substantive difference. Weird. Then, for grins and chuckles, I tried running the toaster monitor out into my Quilter Tone Block 200 into the Gemini 1-P, and it really opened it up. I went back and looked at the Icepower 1000A -3dB upper bandwidth spec, it's only 3 kHz (albeit at 4 ohms, likely a little higher at 8 ohms). The Quilter Tone Block 200 has an upper -3dB BW limit of 10 kHz (I know, I emailed Quilter Labs about it, Pat Quilter answered me personally and told me the bandwidth). That explained the more sparkly and open sound, it was getting close to the direct-through-PA tone I was experiencing.


    I then went and purchased a Matrix GT800FX, which has an upper -3dB BW of 24 kHz, and I now enjoy even more high-end goodness out of my rig. It sounds darned near just like the PA tone. My bandmates have stopped complaining about the blanket-over-the-amp tone from my cab, another benefit of higher bandwidth.


    I have purchased a KPA unpowered rack unit and intend to use that with the GT800FX for live use, and I'll use the toaster with the Quilter for rehearsals and recording. So all's well that ends well.


    If I had known then what I know now, I would not have purchased the Powerhead, I would have just bought the unpowered version and used an external power amp with wider BW for driving a cab, as well as just biting the bullet and buying a good FRFR cab. I know, I know - if I didn't like the tone, why didn't I just skip the cab altogether and go with the PA and some monitors maybe some DXR10s? Well, I LIKE having a cab behind (or sometimes in front of) me interacting with the guitar, and I like the traditional cab look. Just my druthers. Anyway, I thought I should share the results of my experience with you all, it may help someone else shorten their path to tonal Nirvana with their Kemper. .

  • I went through several setups too before I fell in love with the same rig. Unpowered rack Kemper, Matrix GT800 and 2 Mission Gemini 1-P cabs. Now if I could only play better.....

  • So glad I bought the Matrix. I am wondering why there are so few Kemper users endorsing such a great product. Coupled with their proprietary 212 cabinet all I can say is HOLY F*****ING SMOKE!



  • Nice that you have found your tone.
    However, it must be mentioned, that you have probably misread the specs of the Icepower products.


    The power amps go up to 30 kHz with an error of less that a dB, according to the specs.
    It is likely that you have looked up the phase responce graph, instead of the frequency responce.
    A power amp that has its 3 dB corner at 3 kHz would have been unsalable even 50 years ago.
    We have never got a report in the past that our build in power amps attenuate the highs.

  • Howdy,


    Yep, the 3 kHz BW is something from the old AM tube radio era. We're talking pre-Armstrong here! :)


    I was for certain not looking at the phase response, it was definitely the frequency response curve. The 1000A has a 3 dB BW of 3 kHz, see page 6 of the 1000A datasheet (http://www.icepower.bang-olufs…ons/icepower1000adata.pdf). Top curve is amplitude response. It also states this value in the table on page 5, Typical value of the Upper Bandwidth Limit @ Rload = 4 ohm is 3 kHz. According to the curves, the 4 ohm/8ohm/16 ohm responses are almost identical.


    The Icepower 1000ASP has a 3 dB BW of approx 30 kHz. This is as shown on page 9 pf v1.5 datasheet (http://www.icepower.bang-olufs…s/icepower1000aspdata.pdf). This agrees with the 30 kHz value.


    It comes down to what is in there. I haven't wanted to open it up and look at what is inside, I'm afraid to void the warranty. Can you please tell me which one it is? That will put it to rest.


    Thanks!

  • I suspect this is an error in their documentation.
    Every other doc shows a responce beyond 20 or 30 kHz.


    There is actually no need to worry about the sound of a todays solid state amp. The differences are hardly distinguishable in general.

  • FWIW, I contacted B&O regarding the Icepower 1000A bandwidth. It is not an error in the datasheet. Below is the exact communication from their rep, Paul Meister. Take it as you will.


    *************************************************************************************************************************************************************************


    "Hi Nicholas,Your email was forwarded over to me from B&O. Thanks for reaching out. The 1000A was designed (15 years ago) with only low frequency applications in mind. Therefore there was no need to go above 3khz. When the 1000ASP was designed a couple of years later, they thought that they would get more full range applications, so it was designed up to 20khz and everything since then and going forward is full bandwidth.Thanks and regards,


    Paul Meister
    Sales Manager
    ICEpower America 847.909.0093



    Customer (Nicholas Maris) - 09/02/2015 10:02 AM
    (My inquiry to B&O)
    I am writing with regard to the Icepower 1000A power amplifier specifications. I would like to check and see if the typical -3dB bandwidth (at 4 ohm loading) value of 3 kHz, as given in the data sheet (see highlighted line on page 5 of attachment) is a correct value? It seems on the low side. Similar products, such as the 1000ASP, have a BW of greater than 20 kHz. Also, are there any - 3dB BW measurements at 8 ohm loading for the 1000A? Any errata sheets for the data sheet? Thanks for the help!"