Pioneer QX-9900


Pioneer QX-9900 Faceplate


This is one of Pioneer’s four channel offerings – the Pioneer QX-9900. The QX-9900 was manufactured in the mid 70’s and featured both Matrix and SQ decoding. It’s rated at 38 watts per channel into 8 ohms and 50 watts at 4 ohms in to four channels. This unit has the distinctive holes in the top of the case.


Pioneer QX-9900 Back Panel


It also featured:

  • AM/FM stereo
  • 38×4 into 8 ohms and 50×4 into 4 ohms
  • Two tape in/outs front and rear
  • Two aux inputs front and rear
  • Two phono inputs
  • Loudness on/off front and rear selectors
  • Filters high and low on/off
  • Muting -20db on/off
  • Speakers front + Rear A & B on/off
  • MPX noise filter on/off
  • Headphone outputs front and rear
  • FM muting on/off
  • Modes – 2ch stereo, matrix regular, SQ, discrete
  • Selectors – AM, FM mono, FM auto, phono one + two, aux one + two
  • Meter levels -10db on/off -20db on/off
  • Balance front right/left, rear right/left and front to rear
  • Reverberation – time/min/max and modes for front – rear – mode off – mic
  • Left + right mic inputs
  • Left + right mic mixing control knobs
  • Separate treble and bass controls front/rear
  • Tuning and signal meters
  • 4 power meters for each channel


Pioneer QX-9900 Inside


While the Pioneer QX-9900 is fairly rare it’s not a hotly desired receiver. Still, in very good working condition they can sell for up to $400.

Awesome PIONEER QX-9900 Quadraphonic / Vintage Stereo Receiver - Pro Serviced!

End Date: Thursday Dec-19-2019 19:04:54 PST
Buy It Now for only: $986.35
Buy It Now | Add to watch list

Awesome PIONEER QX-9900 Quadraphonic / Vintage Stereo Receiver

End Date: Friday Jan-3-2020 22:59:39 PST
Buy It Now for only: $899.99
Buy It Now | Add to watch list

Pioneer QX-9900 Quad Receiver Parting Out Amp Boards+ SInks + Outputs

End Date: Monday Dec-30-2019 5:28:05 PST
Buy It Now for only: $99.99
Buy It Now | Add to watch list

Pioneer QX-9900 Quad Receiver Parting Out Multi Voltage Power Transformer

End Date: Saturday Jan-11-2020 11:21:27 PST
Buy It Now for only: $49.95
Buy It Now | Add to watch list

8 thoughts on “Pioneer QX-9900

  1. Have had the pleasure of owning a few of these. If in good condition, cleaned properly and tuned up, it is a VERY beautiful looking and sounding machine. Incredible sound, very nicely organized controls and good looking face panel. Lots of power, little distortion but…very, very heavy. Over 50 lbs, so not very compatible with flimsy furniture.
    But, drives ANY speaker you connect and you can connect a ton of them. If you can get one in good shape, clean it right and treat it well, you will not be disappointed in it.

  2. I have one in perfect condition I am looking to sell if anyone is interested. It was my dad’s and he has passed away and I need to declutter. 785-383-4017

  3. Had purchased one when they first came out while stationed in Germany 1974. Had it for a long time and made the poor decision to give it to my step-daughter. she sold it for her drug habit. Wish I had kept it. Have been looking for one ever since. Are you looking to sell it and if so for how much.

  4. Ich habe noch einen im gutem Zustand.
    1. Haken : Er knallt die Sicherung raus nach dem ich in angestellt habe (habe Fi ) .
    2. Haken : Gibet net:

    für nen realistischen Preis würde ich ihn abgeben.

    Gruß Pascal

  5. My name is billy Walker and I live in Larned Kansas. I’m looking for qx 9900 in perfect shape. I had one when I was in the army many years. Bought it new in Korea in 1973.

  6. Hello I’m Randy from San Antonio,to I’m selling a qx-9900 pioneer reciver in excellent shape 10/10 if interested please text 210-834-2174

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Do NOT follow this link or you will be banned from the site!
Scroll To Top