FAQ
TL;DR: Using 6 Ω woofers boosts output current by about 33 % compared with 8 Ω loads [Elektroda, Tremolo, post #2310040] "Turn it down when you hear distortion" [Elektroda, J. S., #2305888]. Add a 2-way Linkwitz-Riley filter at 3 kHz and avoid full-volume bursts.
Why it matters: This setup lets Diora WS-442 owners match modern STX/TVM drivers without frying amps or tweeters.
Quick Facts
• Diora WS-442 rated 2 × 35 W RMS @ 8 Ω; transformer ~120 W total [Elektroda, Anonymous, post #2318446]
• Current rises ≈1.33× when load drops from 8 Ω to 6 Ω [Elektroda, Tremolo, post #2310040]
• Safe listening level: stop before audible “wheezing” or clipping [Elektroda, J. S., #2305888].
• Linkwitz-Riley 2nd-order crossover parts for 3 kHz, 6 Ω woofer: L=1.3 mH, C=6.6 µF (calc).
• ARV-104-04-8 tweeter needs −3 dB pad; power after filter ≈5 W [Elektroda, Tremolo, post #2310040]
Can I safely connect 6 Ω STX woofers to a Diora WS-442 rated for 8 Ω?
Yes. The amp tolerates 6 Ω loads if you keep volume below clipping. Several users run 4–6 Ω speakers without failures [Elektroda, Hefajstos, #2306480; #2323249].
Will adding series resistors protect the amplifier?
No. Extra resistors waste power and overheat [Elektroda, Q-mac, post #2304352] Focus on sensible volume and adequate heatsinking.
How far can I turn the volume knob?
There is no fixed angle. Stop increasing once distortion or “wheezing” appears [Elektroda, J. S., #2305888].
What crossover type and cutoff work best for STX 18-120-6 + TVM ARV-104?
Use a 2nd-order Linkwitz-Riley at 3 kHz. It offers flat summation and manageable tweeter load [Elektroda, Tremolo, post #2311276]
Which inductor value gives a 3 kHz woofer roll-off on 6 Ω?
Approx. 1.3 mH in series achieves 3 kHz. Two smaller coils can be wired in series; keep them 5 cm apart to avoid coupling [Elektroda, J. S., #2319796].
Does the tweeter’s 45 W rating risk burnout during parties?
Unlikely. After the filter the tweeter sees only a few watts; it also gets an L-pad drop, lowering stress [Elektroda, Hefajstos, post #2316802]
Edge case: what happens if I run full volume into 4 Ω speakers?
The WS-442 reaches full power near 0.4 V input; beyond that it clips hard, overheats, and may blow output transistors [Elektroda, Tremolo, post #2310040]
How do I calculate capacitor and inductor values quickly?
Use AJDesigner’s 2-way calculator; enter driver impedances and choose Linkwitz-Riley alignment, then round to nearby E12 parts [Tremolo, #2310040].
Will coil DCR raise system impedance?
Yes. A coil with 0.4 Ω adds that resistance in series, so the amp “sees” roughly 6.4 Ω at low frequencies [Elektroda, J. S., #2321238].
Simple 3-step guide: wiring the speakers and crossover
- Mount woofer and tweeter in the cabinet with gasket tape.
- Solder the 3 kHz Linkwitz-Riley network (L-C on woofer, C-L on tweeter), observing polarity.
- Add an −3 dB L-pad before the tweeter, then connect to amp terminals—test at low level first.
What potentiometer law suits volume controls?
Logarithmic (code B in EU, A in Asia) tracks perceived loudness best [Elektroda, Hefajstos, post #2332480]
Can I cool the WS-442 with fans?
Yes. One or two 80 mm fans on the heatsink keep transistor temperature down during 6 Ω operation [Elektroda, El_liero, post #2318044]
Why disable the loudness/contour switch?
Contour boosts bass around 100 Hz, which strains small woofers and causes muddy sound under high volume [Elektroda, Anonymous, post #2318446]
What’s the maximum clean power from the WS-442 into 4 Ω?
Roughly 50 W per channel; the 120 W power transformer limits further increase [Elektroda, Anonymous, post #2318446]
... because I will be mounting 2 or 1 fan on the heat sink with power terminals ...
You can get the maximum of 50W / 4? of pure signal from it.
