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Chorus chip Transplant

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After thirty-something years, many instruments that use the famous Panasonic designed MN3007 or MN3009 bucket brigade delay lines are now displaying symptoms of noise and it may be time to consider a chorus chip transplant.

Matsushita MN3007 BBD chips inside the Roland SBF-325
Original Matsushita MN3007 bucket brigade delay lines inside the Roland SBF-325. Note the factory-fitted IC sockets.

Initially, the sound when passing through the chorus, seems to contain artefacts. As the degradation of the substrate worsens, the chorus becomes increasingly noisy and can even have a kind of crunch to it (distortion). Do not however, confuse noise generated within the chip with LFO leakage into the audio path. This is quite different and can usually be tuned out via pre-set potentiometers in processors like the SBF-325.

Fortunately the MN3007 is still available and Xvive has released a design of the MN3009 which I think sounds amazing.

Xvive MN3007 and MN3009 bucket brigade delay-lines
Xvive MN3007 and MN3009 bucket brigade delay-lines.

Here's a list of some Roland instruments, processors and amps and the chorus chips that they contain:

  • SDD-320 Dimension-D (2 x MN3007)
  • SBF-325 (2 x MN3007)
  • MKS-10 (2 x MN3007)
  • MKS-20 (2 x MN3007)
  • JC series guitar amps, like the JC-120 (1 x MN3007)
  • VP-330 (2 x MN3009)
  • SA-0 (2 x MN3009)
  • Juno-6 (2 x MN3009)
  • Juno-60 (2 x MN3009)
  • Juno-106 (2 x MN3009)
  • Juno-106s (2 x MN3009)
  • HS-60 (2 x MN3009)
  • Alpha Juno 1 (2 x MN3009)
  • Alpha Juno 2 (2 x MN3009)
  • JX-3P (2 x MN3009)
  • JX-8P (2 x MN3009)
  • JX-10 (4 x MN3009)
  • MKS-30 (2 x MN3009)
  • MKS-50 (2 x MN3009)
  • MKS-70 (4 x MN3009)

I charge a standard £100 plus VAT (£120) to change the chips in all of the above machines with the exception of the Super-JX (JX-10 and MKS-70) which will cost £130 plus VAT (£156).

Two Xvive MN3009s on top voice-board of Roland MKS070
Here are two of the four Xvive MN3009s sitting in the top voice-board of a Roland MKS-70.

High-quality turned-pin sockets are fitted before the chips are installed and the new replacement devices then simply plug into the sockets. This means that they can easily be removed without desoldering, anytime in the future,

In my humble opinion, the new devices from Xvive sound very solid and not airy like the original chips. With definition and detail, you'll defiantly hear a substantial difference in your tone. If you'd like to book in your machine, please just contact me or check out the Chorus Chip Transplant item in my store.