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"HagClock" Low Noise Oscillator ($29 kit/2) Order now!

The HagClock low noise oscillator is intended for use as a reference clock in CD players and transports. It employs a number of circuit improvements over the classic sinewave oscillator design, enhancing performance in all respects. The built-in super-regulators make installation simple, requiring no additional circuitry.

Check out this review #1.

Click for a larger image
Completed HagClock


  • Ultra-low jitter output
  • Built-in super-regulators
  • Easy installation
  • Crystal selectable frequency


Frequency+/-10ppm (adjustable)
Rise/Fall Time<5ns (20% to 80%)
Jitter<10ps rms?
Startup Delay<100ms
Size3.7" x 1.7" (PCB)
Input Voltage+/-8V to +/-15V (+45mA, -20mA)


The HagClock has a low impedance output buffer that is tuned for driving a short section of twisted pair transmission line (CAT5). The waveform below shows the actual response using 6" of line and a 100 ohm series termination into a 10pF scope probe load. Such care to impedance matching eliminates ringing and reflection distortion and keeps noise to a minimum.

Output waveform

HagClock starts up in 100ms after external power is applied.

Startup delay


Customer Testimonials

  • I finally got the Hagclock installed tonight. The process was a lot easier than I thought it would be - remove three parts, attach 4 wires and voila. First impression: WOW! Bass out of nowhere, clarity, clarity, clarity and a 3D soundstage with tons of detail and feel. It's like vinyl without the rumble, pops and hiss. All this without scoping the output on an oscilloscope (which I'll do soon at a friends). You've got a winner with the Hagclock, Jim.
  • Just got the HagClock today and had it installed in less than 45 minutes, the instructions were very clear and (imho) near foolproof. After a short burn-in I was hearing deeper bass and none of the treble "grit" I've grown used-to. I can't wait to hear the thing after it's fully settled in. Thanks for offering this excellent product at such a reasonable price.
  • So I replaced the part with your clock and we were amazed by the increased Bass depth and authority as well as a more relaxed and natural top end.
  • I thought I would check in with you about the [HagClock]s installed in my Musical Fidelity CD player. Well, I can only say that the player sounds like a much more expensive unit. Everything is better, even the speakers seem bigger. The resolution is much higher, and I hear everything that comes with it. Better bass, more musical, sweeter highs, great midrange, more analog-sounding, etc.
  • Your clock is a beautiful design! Installation was only 20 min. I have a decked out Marantz Heart CD-6000 that sounded great in stock form but now it sounds better than a live performance. Stunning stage presence and terrific definition with excellent separation. Impressive product!! It will make you worst recordings come alive. Thank You so much.
  • Whereas I was thinking that I would have to buy a new and more up-to-date transport and/or DAC to achieve the sonic improvement I was seeking, I can now report that your clock has taken my system to new levels of listening pleasure and I will happily stick with what I now have for the foreseeable future. I installed the clock in my Rotel RD980 transport and that is feeding my Assemblage DAC2 (heavily modified). Music is now much more dynamic, detailed and clear. There have been a number of levels of noise removed from all recordings, so instruments are more clearly defined as are recording venues. I don't know if the bass is deeper, but it sure is cleaner and tighter.