Trinirides.com - T And T Most Advanced Online Auto classifieds

Components
Genesis employs 85 C capacitors when 105 C caps should have been used in an automotive environment. Come on guys, pony up some quality caps! All other components are top quality.

Crossovers
The limited maximum frequency of 200 Hz may be too low for certain applications.

Frequency Response
The excessive high frequency response means that all audio cables should remain short and well away from speaker cables. (Prudent advice in any system.)

Muting and Turn-on/Turn-off Noise
The Genesis appears to use no form of muting. When muted, the amplifier continues to pass audio for about 300 mS. If the deck that drives it thumps prior to this, you'll get a nasty thump. You'll have to carefully select the head unit for this amplifier, one that maintains its output a half a second after muting. Turn-on delay is a bit short, only 1.7 seconds. This does not give other equipment in the audio chain time to settle and will likely cause a turn-on thump. We were concerned that the 300mS turn off delay would cause a turn-off thump with certain decks. Most amplifiers mute their outputs within a few milliseconds after the mute line goes low. But we did not detect any muting noise whatsoever with our Clarion head unit. The Zapco SP7 EQ does not have a long turn-off delay, thus this combination did have a nasty turn-off thump, so you will have to be choosy about the audio equipment used with the Genesis.

Protection
From the purist's perspective, protection might be intrusive in the audio path. This amplifier offers none except fuses. We did short the outputs, causing the fuses to blow. Operating the amplifier into a 1-ohm load also blew the fuses. We did not short the amplifier at high temperatures, where this type of protection might not protect the amplifier. So, don't over-fuse this amplifier and expect it to live through a speaker short.

Power Supply
The supply is unregulated, causing the power to drop at lower supply voltages. Output power is at 12 volts, 20 Hz is 95 watts per channel. At 14.4 volts, 20 Hz, this amp delivers 140 watts per channel. Also unregulated supplies cause the amplifier section to run hotter than regulated designs without adding anything significant in transient power.

Reactive Load Test
The designers decided to leave off the customary output inductors found in most amplifiers. These inductors are shunned by the audio purist, as such the output stage is at the mercy of reactive loads. We found that the amplifier would ring or oscillate when loaded with anything bigger than .02uF at the speaker terminals. Fortunately the speaker wire itself adds enough inductance to keep the amp stable. It still oscillates with cap values greater than .27 uF with .5 meter speaker wire. You'll want to be careful when driving electrostats or other capacitor loads.

Performance
The amplifier produced plenty of power with low distortion. Four-ohm distortion was under .03% THD at virtually any power level below clipping. Two-ohm THD was < .1% below 240 watts per channel. Because of its unregulated power supply, power dropped to 95 watts per channel at 12 volts/20 Hz @ 4 ohms. Distortion remained very low even at 1 watt power levels.

The bandwidth was limited on the bottom end by the 20 Hz high pass crossover which could not be switched out. The high-end response was only down .7 dB at 100 kHz.

It is hard to measure actual slew rate as an audio equipment's frequency response should always be passively limited before active circuitry. Slew rate appeared to be a very respectable 20 volts/mS. Passive input roll-off may have reduced the apparent slew rate somewhat.

Listening Test
Circuit design and electrical specs tell me what I need to know: this amplifier does not alter the audio in any perceivable way. Low THD and transient distortion at all power levels puts this amplifier in the audiophile class. We tested the Genesis with Morel Duets and the Altec Lasing Voice of the Theater. These old Voice of the Theater speakers are extremely efficient and help reveal low power distortion. The audition verified what I expected: This amplifier passes audio without coloration.

Conclusion
The Genesis Dual Mono has everything I like in an amp: High output current, low THD, and a fast slew rate. The dual mono setup has very high separation and also isolates the left/right ground loop. This is an extraordinarily clean amp, I highly recommend it!

Specifications
Output Power at .2% THD, 1 kHz, 14.4 Volts
Stereo @ 4 ohms	2 x 150 Watts
Stereo @ 2 ohms	2 x 247 Watts
Bridged @ 4 ohms	1 x 494 Watts
T.H.D, 1 kHz, 14.4 volts
<.03%	4 ohms	2 x 145 Watts
<.1%	2 ohms	2 x 245 Watts
Frequency Response (.125 dB)	20-20 kHz
S/N Ratio (A wtg., Below clipping)	> 113 dB
Transient Distortion (100W)	< .007% @ 4 ohms
Input Sensitivity	105 mV - 4.5 volts.
Lowpass Level Control	5.5 dB
Crossover slope	12 dB / Octave
Crossover range - highpass	20 Hz - 200 Hz
Crossover range - lowpass	50 Hz - 200 Hz
Input impedance	20 K ohms
Muted current	1.5 mA
Idle current	2.2A
Maximum current	52A @ 500 watts
Dimensions	W x 2.35" H

< Prev		Next >