Reviewed by: Paul_Bui, Audio Enthusiast from Milpitas, CA,

Price Paid: $1995 at www.decware.com

Product Model Year:
2001

Summary:
This is a follow-up review after over a year of using these monoblocks to drive relatively high efficiency speakers such as the Radials RL-1s and RL-2s, and the Horns from TheHornShoppe.

Unlike most SET amps, these SV83Ms prefer lowish impedance speakers. While they don't like such high impedance beasts as the Moth Cicada (12 ohm 94 db), they'll be much happier driving speakers of 8 ohms or lower. I even think they deliver most power transfer into 4 ohm speakers, provided crossover kept to minimum or none and efficiency at least 90 db.

I get the most satisfying sound from them driving the Horns with the ZERO Autoformers installed between the amps and speakers, and two REL Storm IIIs. There is a good balance of speed, slam, midrange presence and detail, low bass extension and agility, highs detail and extended as far as the Fostex Fe108 Sigma drivers go. Sources are the Vecteur D-2 transport linked with the EVS Millennium 24/96 DAC II (discontinued).

Although tube biasing is done automatically, the amp has a toggle bias switch in front that lets the listener choose between a purer sound with truer tonality signature or a bass boosted more powerful presentation. It's like having two amplifiers for the price of one.

Besides, there are two rocket switches in the back for POWER and STANDBY. I always start by switching on the STANDBY while leaving the POWER off. In this mode all tubes get the power but can make no sound, so I can make any cable or interconnect swap while letting the amp warm up (very useful feature if you're to compare, say, two speakers or cables or even sources).

These low powered amps have excellent speed and accurate timbral presentation. Their soundstage is deep and wide beyond speakers (and exceeds room dimension sometimes); image specificity and size are pretty good and even better when impedance is matched between amp ans speaker.

I'm still exploring these amps. They won't be replaced by any super amps for a long time.

Strengths:
Transparent, detailed
Keep on improving with months of use
Can drive 2 ohm load
Lifetime warranty
Reliability - never had a problem for the last 18 months of use
Look gorgeous
Tubes not that expensive to replace

Weaknesses:
As a low powered SET amp, will likely to clip when asked to drive speakers of efficiency lower than 90 db at high volume levels or speakers with complex crossover networks.