HCAT Model DF-100.2 X10 Mk III Stereo Amplifier





Recently I exclaimed over the new X-10 components from North American Products, I still do, but their new amp just far exceeds the earlier versions. What is achieved within this amp focuses on seeking to replicate music in the air, such as what you would hear in a live performance. In his white paper on their webpage, “The air serves as the perfect medium allowing the sound vibrations generated by the various instruments on the stage to “travel” as waves uninterrupted.” Every note that left the stage at one time arrives at the same time. Within the new circuit, any speed difference in the speed of all frequencies stays the same.

This was always the goal of the H-Cat circuits. This version achieves what Roger Paul acclaims as completely accurate. While it took three weeks of breakin, I would totally agree. I never have heard what I’m hearing never before. Mr. Paul used to call this “holographic,” but now he says, and I agree, it is like being actually at the performance or recording studio. Of late, I have been an enthusiast of “realism.” I think he and I are talking about the same thing. I might add, however, that the most accurate rendering of the music using components is from the perspective of the microphones, not of sitting in the audience. But that said, we cannot really expect more as that is how the music is captured. Perhaps a microphone tree placed in the fourth row, center, would give the audience perspective. But there are many performances that I cannot wait for such recordings.


This H-Cat amp provides an ease of sound, as well as a full frequency response from very low bass to the lead edge of piano and brass. You hear very well controlled bass to percussion bells that just sparkle and you can hear the end of the notes. Everything takes on realism as you can hear the musicians move about, the subtle character of the vocalist, and, of course, the timbre of instruments, which for me often is the ripeness of brass.

But there is an unusual characteristic that I could not put my finger on for a long time. I could not articulate it for a long time when I was reading the “white paper” and listening to Count Basie’s, Live at the Sands (before Frank), Reprise/WEA B000009D1P. It was like being before the big band and I had a sense of where all instruments were. I read, “H-CAT™ functions in a “zero error” environment. In this mode it produces a cloned wave structure. It allows the amplifier to pass an unlimited number of sound objects in an effortless projection. The imaging for a full orchestra is just as clear as it is for two or three instruments.”

This was what I was hearing and later listening to live stage performances or symphonic works brought this home to me that this was an attribute of this amp. I also tried this on vinyl and found it even more true there. The amp recreates the full sound stage before me even with massive numbers of musicians or choir members. And they are all located from the extreme left to the extreme right. This is realism at its best.

This amp has a 100-Watt output and a dynamic range of over 130 dB with a gain of 23 dB. I have listened to very loud performances, such as Huge Masekela’s Stimela at appropriate high volume and heard no strain whatsoever.

Overall, I will be keeping this amp as I kept prior H-Cat amps, but now it will be my reference amp. Right now I really cannot tell you where to hear this amp, but I strongly recommend that you hear it.


norm luttbe


Price: H-Cat DF-100.2 (X-10) Mk III stereo amplifier: $11,995

North American Products

700A South White Horse Pike 

Suite 197

Somerdale, NJ 08083

Email: info@h-cat.com

Website: www.h-cat.com 


  • Armen
    08 February 2016 10:36
    Dear Norm,

    I red you review of X-10 amp with great interest. But I wonder how a single element(X-10 amp), can have such a profound effect in long chain of recordings-from studio to our homes-without a single MACH 1 circuit present in those stages. very strange.

    Best regards,
  • Roger Paul
    09 February 2016 08:28
    Hi Armen,

    Do to the function and location of analog stages, distortion products are much higher in some "links of the chain". for example a phono stage will have more distortion than a line stage. Gain and distortion are proportional. The function of a power amp is to transfer the electrical energy from the amp to the speaker. This makes the power amplifier a special component. It may have the hardest job of all the components when it comes to delivering a stable signal.

    I am designing microphone preamps with the X-10 stage and cannot wait to begin recording.

    • Armen
      22 February 2016 09:44
      Hi Roger,

      Thanks for reply, sorry I didn't noticed it. Anyhow I'm not convinced! I meant if a signal is distorted from start by not using MACH ONE circuit -as it's claimed-how an element in reproduction source can "correct" it.

    • Armen
      22 February 2016 09:45
      Dear Roger,

      I think you haven't received my reply to your email. Anyhow thanks for reply. But you couldn't convince me! What I'm saying is: how a single element in music reproduction chain can "correct" an error during recording session, then being played in a lets say a non MACH ONE CD player and finally being broadcasted by a pair of normal speakers. And have that profound effect.

  • Norm
    30 November 2016 02:23
    I think sound engineers have captured the musical material better than we thought.

    Roger\'s amp passes this material through great amplification throughout the music with no distortion.
  • Barry
    24 January 2017 11:13
    After years of enjoyment,while always striving for the closest reproduction of music that was humanly possible,I have had the awesome privilege of owning, listening to it break in,while continually blowing my mind with the most realistic musical picture I have ever heard from electronics. Due to serious health issues this equipment had sat during my recovery and a major move but is now set up and blowing the minds of every musician and genuine music lover who has heard this \"phenom\". Looking forward thankfully to many years of this level of real music appreciation!
    • Dave
      31 January 2017 14:06
      My search for greater and greater audio realism over 4 decades what given it\'s greatest boost with the H-cat MK IV.
      MY MK III was OUTSTANDING and the Mark 4 is a whole other level of \"real\". I could not have imagined how \"LIVE\' this sounds and could not describe how much better it is than all the amps I\'ve heard since 1979. Phenomena indeed!
      This amp takes a long time to sounds it\'s best. Months of going from great, to amazing, to beyond comprehension.
      Friends I know that have the H-CAT Mark 4 are as wildly enthusiastic as I.