The Pioneer SX-950 Bluetooth path runs through its AUX input (150 mV line level), with two tape monitor loops and a Dolby NR Adapter loop as backups. The 85 W/ch output section rewards a clean source: pick an adapter with LDAC or aptX HD and keep it on fixed output. No soldering, no internal modification.
Spec snapshot
| Item | Value | Notes | Source |
|---|---|---|---|
| Market period | ≈ 1976–1978 | Silver-era, made in Japan | HW, CR |
| Power output | 85 W/ch @ 8 Ω | Both channels driven, THD under 0.1% | HW, CR |
| Phono inputs | 2 × 2.5 mV / 50 kΩ | Phono 1/2, MM cartridge | HW, SM |
| Line inputs | AUX · Tape 1 · Tape 2 | 150 mV, RCA | HW, SN |
| Adapter loop | Dolby NR Adapter in | Rear-panel processor loop, ADAPTOR IN/OUT | HW, SM |
| Pre / Main | Pre out · Main in | Separable pre/power section | HW |
| Microphone | 6.5 mV, front panel | Not suitable for a line-level feed | HW, SN |
| Weight | ≈ 19 kg | 42 lb 3 oz | HW, SM |
| Original price | ≈ $600–650 | 1976 USD list | HW, CR |
Source codes: CR classicreceivers.com · HW hifi-wiki.com · SM Pioneer SX-950 service manual · SN stereonomono.blogspot.com. Data as of September 2026.
Where to connect
AUX input
RecommendedLine level at 150 mV and always active. Turn the selector to AUX and the SX-950 treats the Bluetooth receiver like any other source.
Tape 1 or Tape 2 loop
Good alternativeTwo full monitor loops with dubbing between decks. Select the matching Tape button to listen and switch it off again for the other sources.
Phono or microphone input
Not for line-levelThe MM phono stages carry high gain for cartridges, and the front microphone input expects a low-output dynamic mic. A Bluetooth receiver will overload either one.
Set up in three steps
- Choose AUX
The cleanest door on this receiver, with the tape loops kept free for decks.
- Wire the receiver
RCA out from the Bluetooth unit into AUX, USB power attached, pair once.
- Set levels
Volume low, select AUX, then bring it up. Fixed/line output on the adapter if available.
Quirks and notes
- Two more line-level doors (verified): beyond AUX and tape, the SX-950 has a rear-panel Dolby NR Adapter loop (ADAPTOR IN/OUT with its own selector position) and a separable pre out/main in section. Handy when every RCA input already has an owner.
- Front microphone input (verified): a period feature for announcements and recording. Wrong gain and impedance for Bluetooth, so leave it alone.
- Switch contact crackle (commonly reported): owners report scratchy phono and selector contacts at this age; cleaning treatment is standard restoration practice. Unverified
What you need
- Bluetooth receiver with RCA output, LDAC or aptX HD preferred
- 0.5–1 m RCA cable
- USB power for the receiver
FAQ
Yes. The SX-950 has a dedicated AUX input rated at 150 mV, plus two tape monitor loops and a Dolby NR Adapter loop. A Bluetooth receiver with RCA output plugs straight in without any modification.
The SX-950 is rated at 85 watts per channel into 8 ohms, with distortion under 0.1 percent. That is real headroom for floor-standing speakers in a typical home room.
Any receiver with RCA output and LDAC or aptX HD support. Plug it into AUX, power it over USB, and set the output to fixed/line if the option exists. The tape or adapter loops serve when AUX is occupied.
blafili B3 Bluetooth Music Receiver
RCA output feeds AUX directly; XLR and optical outputs are there when the rack grows. LDAC and aptX HD, OLED status display.
Spotted something off, or own this receiver and want to share a photo? Write to yourfriends@blafili.com. Photos are published under CC BY-SA 4.0 with full credit to you; corrections are verified and applied with thanks.
Share a photo or correction- Specifications, input configuration and price: hifi-wiki.com Pioneer SX-950 page
- Market period, power rating and weight: classicreceivers.com Pioneer SX-950 page, with the SX-950 service manual as the spec anchor
- Aux sensitivity cross-check: stereonomono.blogspot.com Pioneer SX-950 spec listing