EWA M-100 Turbo, by Colin Wonfor. Class A amplifier. front

EWA M-100 Turbo/Turbo S Power Amplifier

Name: EWA M-100 Turbo/Turbo S Power Amplifier
Brand: ABCaudio

£5,850.00

'S' option

chassis

M100 Turbo amplifier and 'Sense' option.
 
Probably the finest low distortion, class A powerhouse amplifier in the world. 
 
Power is everything with control.
 
IEC power inlet as standard.
 
Monoblock versions are now available. There is no extra performance in mono configuration.

The M-100T / TS are based on the M-100, M-50 and even the Q20, featuring 8 pair output devices per channel (16 total) following the massive power devices. The large Bulk set of capacitors (four per channel) are rated at 47,000uF, as part of a fully dual mono, dual differential amplifier.

Bridged/Dual differential, Dual Mono

Input: 10KΩ

Power Output:

150W/8Ω

300W/4Ω

600W/2Ω

Over 30W class A.

Unique dynamic bias system

Bandwidth: >300KHz

DF: >2000 (dynamic)

1W standby / 60W powered, no signal.

430 x 240 x 360mm. 35 Kg.

DC offset is less than 0.5mV

The output stage is run in A/B and has a SECA drive stage. Eight complementary pairs of transistors rated at 25A 125W, driven by 15W 140MHz transistors. The SECA driver is running at 5W. Extremely fast RF transistors are used to increase stability in the amp under non- normal loads i.e. no resistive a speaker with a wicked load line character.

Power supplies can be made for most countries of the world except those on DC.

IEC POWER INLET FITTED AS STANDARD.

BUILD TIME: Approximately 4-6 weeks.
M-100 Turbo 'S'

Bridged/Dual differential, Dual Mono

Input: 10KΩ

Power Output:

180W/8Ω

360W/4Ω

720W/2Ω

1000/1Ω

Over 35W class A.

Unique dynamic bias system

Bandwidth: >300KHz

DF: >3000 (dynamic)

Feed-Forward error correction.

1W standby / 60W powered, no signal.

430 x 240 x 360mm. 35Kg.

Sense is a unique innovation by Colin Wonfor, based on several methods of feed-forward error correction he used in other applications. The following is an oversimplification:

In the case of the EWA M-100 Turbo S, 'Sense' is a feed-forward error correction system that compares the audio signal at the loudspeaker terminals to the input of the amplifier, and dynamically corrects for any difference or losses detected.

(This means an additional set of wires needs to connect to the loudspeaker terminals and run back to a designated terminal on the amplifier. This is not bi-wiring, nor does it create a short circuit. No audio signal uses these wires.)

What is 'Sense' correcting? Starting with any losses on the loudspeaker cable itself (you shouldn't have any losses there - you ought to using EWA), back EMF from the loudspeaker and assorted secondary effects of the crossover network all manifest themselves electrically in the loudspeaker cable and amplifier.

By comparing the the signal at the loudspeaker terminals with the input terminals at the amplifier, every difference (that isn't voltage or current) is corrected, in effect using the amplifier circuit itself to 'EQ' the signal in the analogue domain, utilizing fully the dual differential nature of the EWA circuit in the M-100 models.

So what is the difference? You might expect it to be pretty minor, right?

Wrong. Sense really brings a new level of control and presence to the sound you hear. It can even be seen, on bass heavy material the output is clear, loud, extended - yet the loudspeaker bass drivers appear to move and oscillate less. You'll have to hear the difference, I'm afraid there's not much to compare it to.

EWA M-100 Turbo 'Sense': Power is everything with control.

IEC power inlet fitted as standard.

BUILD TIME: Approximately six weeks.

M-100 Turbo

M-100 Turbo 'S' (sense)