Amplifier recommendations for 86 dB Sensitivity Speakers


Hi,

I’m considering a pair of Technics SB-G90M2, they have good specifications on paper; however, my only concern would be their 86 dB sensitivity. 

My current amplifier is Cayin A100t, which according to its specs, outputs 70 watts into 8ohms. the Technics are 4 Ohms; so, I assume my Amp could deliver 100-140 Watts into 4 Ohms. Unfortunately, I couldn’t find more accurate information about my amplifier, and it only shows the output power at 8 Ohms equipped with KT-88 output tubes (mine came with EL-34s), therefore, it’s unclear what the real output powerat 4 ohms is.

Wondering if this tube amplifier would be a good match for these more demanding 86 dB speakers? I’m aware of impendence fluctuations and I know the Amp can drive them just fine, but I am not sure if 100 watt per channel -assuming that’s what my Amp can deliver into 4 Ohms- would be enough for these speakers to make them sound as intended, meaning, good sound quality.

(I don’t nor am planning to listen at high volume but have a larger room with high ceilings).

Below are the specs.

Many thanks,

 

Technics SB-G90M2 Speakers 

  • Type: 3-way floorstanding speaker with bass reflex
  • Woofer: 2 x 16 cm
  • Midrange: 16 cm
  • Tweeter: 2.5 cm
  • Sensitivity: 86 dB
  • Impedance: 4 ohms
  • Frequency range: 33 Hz – 90 kHz (-10 dB)
  • Crossover frequencies: 500 Hz, 3400 Hz
  • Maximum power handling: 200 W
  • Recommended amplifier power: 40-200 W
  • Dimensions and weight: 111.4 x 29.2 x 36.6 cm / 35 kg

 

Cayin A100T Integrated Tube Amplifier 

Power output: 70 watts per channel into 8Ω (stereo)

Frequency response: 10Hz to 65kHz

Total harmonic distortion: 1%

Input sensitivity: 480mV (line)

Signal to noise ratio: 89dB (line)

Speaker load impedance: 4Ω to 8Ω

Valve complement: 8 x KT88, 2 x 12AU7, 2 x 6CG7, 1 x 12AX7

Dimensions: 440 x 210 x 397mm

Weight: 29kg

mamifero

Technics has gone from mass-market to high-end, keeping its toes still wet as an iconic turntable maker as well. I would think you would want to look at their amplifiers, which I imagine would work well with their speakers. The SU-G700M2 looks very suitable and well-equipped, with a DAC for its digital source inputs. Alternatively, you could consider the Yamaha A-S2200 (or the A-S1200 and A-S3200). No DAC, but excellent and capable with classic design and  traditional preamp controls. 

Importantly and often overlooked is the profile of the impedance curve. These curves can vary typically from 2 to 25 ohms across the entire frequency range.
It would be  nice to get a measurement of the actual impedance curve to see if indeed it does dip down to 2 ohms .
Seems like the more exotic the design, the more varied the impedance curves are.
Check out the specs for the Nilai 500 monoblocks and you will see why the finest class D Amplifiers are acclaimed for their bass control and musicality.

Nilai 500 Specifications

  • THD+N:  0.00015% (-116 dB) @ 100W / 4Ω / 20 – 20.000 Hz
  • 260W  @ 8Ω, 1 kHz, THD < 1%
  • 525W  @ 4Ω, 1 kHz, THD < 1%
  • 500W @ 2Ω, 1 kHz, THD < 1%
  • Frequency response:  0-70 kHz
  • Output noise:  9.5µV @ 11.8 dB gain
  • Gain adjust in three steps:  11.8 dB, 21.8 dB and 27.8 dB
  • Signal to Noise:  134 dB
  • Input Impedance: 47 kΩ
  • Idle power:  14 W typical

I would not consider the speakers that you mention, 86db at 4 ohms is really hard to drive.....as so many have already mentioned. It would greatly limit your amplifier options now and into the future. You would need bigger, high current, high wattage, expensive amplifiers......and basically eliminating tube amplifiers unless you own a Brinks truck full of cash.

There are literally many dozens of amazing speakers that would be better choices in that price range. Spend $5,000 or $6,000 on speakers, and you'll most likely save much more