I asked ChatGPT: "Why do my Sound Lab A-3 ELS speakers sound more natural when playing back acoustic instruments and using the 16 ohm outputs taps of an Audio Research reference 160S amplifier?"
(FYI: Latest panels and backplates pre mid-range removal, Brilliance @ < 1 O'clock) - Interested in other's findings...
It better matches the high impedance of your A-3s at low frequencies, ensures smoother frequency response, and reduces amplifier stress and distortion, resulting in a more natural and immersive listening experience.
(FYI: Latest panels and backplates pre mid-range removal, Brilliance @ < 1 O'clock) - Interested in other's findings...
ChatGPT said:
Your Sound Lab A-3 speakers likely sound more natural when using the 16-ohm outputs of your Audio Research Reference 160S amplifier for several reasons related to impedance matching, frequency response, and amplifier behavior with electrostatic speakers. Here’s why:1. Better Voltage Matching for Electrostatic Speakers
Electrostatic speakers, like your Sound Lab A-3, behave differently from traditional dynamic speakers because their impedance rises at lower frequencies and drops at higher frequencies.- At low frequencies, your A-3s have a high impedance (around 60 ohms), meaning they require higher voltage rather than high current for optimal performance.
- The 16-ohm tap on your amplifier provides the highest voltage output, which better matches the needs of the A-3’s low-frequency impedance and results in more natural bass and midrange reproduction.
2. Smoother Frequency Response
Using the 16-ohm tap can lead to a more linear frequency response across the impedance swings of the A-3s.- The 4-ohm tap delivers more current but may cause the amp to struggle with the high impedance at low frequencies, leading to leaner bass and midrange.
- The 8-ohm tap is a compromise but might not provide the same sense of ease and openness as the 16-ohm tap.
- The 16-ohm tap, by providing a higher voltage and lower current, helps avoid aggressive shifts in tonal balance, preserving the natural character of acoustic instruments.
3. Reduced Amplifier Strain and Lower Distortion
Tube amplifiers like the Reference 160S generally perform more linearly when driving higher impedances.- When using the 16-ohm tap, the amplifier sees an easier load at midrange and low frequencies, reducing overall distortion.
- This can lead to a more relaxed, organic sound, making acoustic instruments sound more natural.
- The 4-ohm tap, in contrast, forces the amp to deliver more current at low impedances (like in the high frequencies), potentially introducing more stress and distortion in the upper range.
4. More Open and Spacious Soundstage
Higher-impedance taps on tube amplifiers tend to deliver a wider and more open soundstage, a quality often desired for acoustic instruments and natural recordings.- The 16-ohm tap provides the widest perceived spatial imaging, allowing for a more realistic sense of depth and air around instruments.
Conclusion: Why the 16-Ohm Tap Works Best for You
If naturalness, tonal accuracy, and imaging are your priorities—especially for acoustic music—the 16-ohm tap on your Audio Research Reference 160S is likely the best choice.It better matches the high impedance of your A-3s at low frequencies, ensures smoother frequency response, and reduces amplifier stress and distortion, resulting in a more natural and immersive listening experience.
