Ok, first of all I'll be honest. I bought this amplifier after reading the reviews here. I've got it for pennies and had to be matched with a pair of Heybrook HB2 speakers using a NAD 3020 as a preamplifier. I had my jaw dropping on the floor when I listened to it. I can say that the only thing I had (because I like to speak based on personal experience) that sounded that like was an Onkyo Integra M-5099 with its preamp P-3099. Obviously there was more power there but the sound fingerprint is the same: REAL. Music is music because played by real instruments and sang by real people. If you have the chance to get one it will become the Hi Fi bargain of a lifetime. I would congratulate myself with the engineering that made it if I knew who he is. Bravo!

RCA input and decent speaker cable connectors would have been killer on this machine.

Simple: The ALESIS RA-100 is a problem-free, well-engineered, well-protected, hugely under-rated amplifier. Being as popular as it once was, you can find them from $40 to $100 on EBay all day long. They're missing "a zero", and should cost $400 to $1000. But they are darn-inexpensive. Being an amplifier DESIGNER (me), I can say that the most impressive part of the circuit used is that it is totally protected against all abuse. Accidental shorting of output. Leaving it shorted for great lengths of time. Putting the wrong pins on the input. Feeding it WAY too much voltage on input due to ground-loop issues, or to 220 / 110 volt power-phase-plug issues. The other side is that the circuit is highly linear with only modest corrective/adaptive negative-signal feedback. It is an amplifier that is quite UNDERRATED in terms of what it can take in, and output, before clipping. 100 watts into 4 ohms is 100 MUSIC watts. Peaks can easily exceed 300 W. A very fine thing indeed. LASTLY, I can vouch for this amp when it is stacked "5 high" in a large live-music mixing rack. We have 5 of 'em in a custom-built rolling digital mixer rack (Yamaha 01V) powering a total of 10 around-the-church speakers of various vintages and designs. Live music is essentially MONO of course, but each of the 10 speakers requires different settings for how much power they receive relative to the general driving level. What a convenience! 10 knobs. A laminated identifying label on each knob. A laminated "sticky-arrow" on the rotary scale indicating the "best level to set". A kid can do it right. Moreover, having the 4 monitor speakers being the top two RA-100 amps gives a "go to quickly" access to the knobs to adjust things like runaway feedback. Our church seats 1,000. Its a "long catholic church" in the outline of a big crucifix. Over 100 feet long by 50 feet wide. BIG church. We put 1 high-sensitivity "Bag End" brand speaker in the rear, in the choir loft. It is on a 125 foot 14 gauge bright orange piece of 3 wire construction-grade power cable. SpeakON connectors at both ends. (We modified all speakers to have SpeakON connectors). Likewise, we use 4 speakers on the long central hall, left-and-right. That's 5. The 6th speaker is on the "crossbar" across from the ground-floor orchestra-and-choir area. The orchestra-and-choir area has 4 monitors, so it produces enough sound level on its own without outfacing speakers. By doing this, we also

The fact that it is inexpensive. And has crappy speaker connections. But the speaker connections are "fixable" with a bit of hands-on-Do-It-Yourself retro-engineering. We installed SpeakON connectors in all units. Took about a week for the engineer-kind-of-guys to get 'er done. Looks great, works great. Never look back!

SUMMARY.
BOUGHT THIS AMP ON EBAY AS A STOPGAP WHILE DECIDING ON NEW AMP FOR MY SETUP.WAS CONNECTED TO MUSICAL FIDELITY CDPRE 24 DRIVING KLIPSCH CORNERHORNS.FOR THE MONEY PAID @220 I WAS AMAZED AT THE QUALITY OF SOUND THIS AMP PRODUCED .CLEAN ,DEFINED,OPEN ,NEUTRAL WITH A GOOD SOUNDSTAGE.A LITTLE BIT ROLLED OFF ON THE TOPEND BUT THAT SUITED THE CORNERHORNS WHICH CAN BE A LITTLE TO AGGRESSIVE.I HAVE HAD NUMEROUS AMPS OVER THE YEARS AND ALTHOUGH THIS AMP CAN BE BETTERED YOU ARE GOING TO HAVE TO SPEND A LOT OF MONEY [THOUSANDS] TO FIND A SUPERIOR AMP-THIS AMP IS THE BEST BARGAIN I HAVE EVER HAD IN 35 YEARS OF HI FI BUYING AND HIGHLY RECOMMEND TO ANYONE ON A BUDGET

OTHER EQUIPMENT OWNED
MUSICAL FIDELITY,HARMON KARDON CITATION, MARANTZ,PIONEER ,ROTEL,CYRUS,ARCAM,AKAI PRESTIGE SERIES,DYNACO[VALVE AND SS]YAMAHA,NAKAMICHI,KLIPSCH,MORDUANT SHORT

STRENGHS
OPEN CLEAN NEUTRAL SOUND

WEAKNESS'
SPEAKER CLIPS

I use this amp in two configurations...one as a DJ rig and the other as a home studio. I have Alesis near field monitors and some kick-ass Advent speakers for the DJ events. Too bad Advent is not what it was in the 80s

Very clean sound. Consistent build and sound quality. No fans.

Spring-clip speaker connectors.

I own several of these (5 and counting), all purchased off of eBay. I am using them in combination with active crossovers and custom made speakers. I have been impressed with the fact that all of the amps have the same sonic signature -- clean but a little constrained on the high end, which suits my listening preferences just fine. All 5 of the amps have been remarkably consistent in their operation with absolutely no problems. These are not high-powered amps, however they provide plenty of power for studio use or for my situation where I am using 3 channels (from 2 amps) per 3-way speaker.

Very clear, clean open sound, not at all edgy or harsh. Stands up extremely well to a very decent pair of speakers.

I actually like the 1/4 inch inputs -- they really work superbly although it means you have to buy your cords from a pro audio supplier. The cheezy spring clip speaker terminals are a truly weird feature on an amp of this quality, though. I gladly would have paid some extra bux for better terminals.

I took the approach another reviewer mentioned -- I got a clean, minimally featured amplifier, dispensed with a pre-amp and spent my money on speakers. The amp sounds beatiful and works great. If you can still get a closeout special on the RA100, I would recommend it highly. And if you can''t, I suspect that the new series from Alesis sounds equally good. I ended up with another great closeout bargain on speakers (B&W DM605 S2''s), plenty good enough to reveal any defects in the Alesis if there were any. And I noticed that when I said I had an Alesis, the folks at the fancy audio parlor where I bought the speakers stopped even trying to sell me an amplifier to go with the speakers. Of course, this is only a 75wpc amp (8 ohms), so if you want concert sound levels you might need to get something a little heftier.

Similar Products Used:

None lately -- I made do for many years with a consumer gear receiver.

Excellent detailed sound, does just what it says on the box! Only 2u high and heatsink-cooled. Well priced, bargain on the used market.

only has 1/4'" unbalanced inputs, dreaded spring-clip speaker connectors. Plastic front panel.

Aside for the minor quibbles mentioned above, this things excells at it's main objective, which is to provide un-coloured power for monitor speakers. Nevermind esoteric high-end hi-fi costing 1000's of dollars, this thing will probably outperform them for a couple of hundred bucks. I run it with a pair of Rogers LS3/5a's which can be fussy with what they're paired with and they sound excellent. The soundstage is wide and open, with tons of detail but still sounding musical. This amp will reveal every little shortcoming in the rest of your system though! I tried a $1000 C-Audio power amp as well and the Alesis beat it easily.

Similar Products Used:

C-Audio

musical; tremendous price/peformance; functional; sleek outlook?

input/output design

Hi, I've just got a more complete specifiction of this outstanding product. Here it is!

Output Power: 100 watts into 4 ohms, 75 watts into 8 ohms, per side
THD: 0.05% THD @ 1kHz (8 ohms), 0.19% THD @ 1kHz (4 ohms)
Frequency Response: ±1dB 20Hz - 20kHz
Recording studio reference monitoring
Live sound reinforcement for small venues
Noise: 100dB below full output
Damping Factor: 200 @ 8 ohms
Input Sensitivity: .5 VRMS for full output
Input Impedance: 7k ohms, unbalanced
Input Connectors: 1/4" phone jacks
Output Connectors: 1/4" phone jacks and push clip terminals
Power Requirements: (US Domestic) 120 VAC, 500 W Max
Dimensions: (WxHxD) 19"x3.5"x8"
Weight: 14.25 lbs

If you find this, get it on the spot. You will NEVER be disappointed.

Similar Products Used:

Audio Innovations Alto, Classe CAP-80 (just a crap), Creek 4040s2, Harmand/Kardon PM-625, Nikko Alpha II (this is great), Rega Elex

price, quality in sound and construction, design concept (no need for preamp if you have just one source)

poor speaker outputs, no RCA jack, power handling info is misleading

This amp is awesome. I love it for three reasons.

First, I love its design concept. This dispenses you with a preamp if you have just one source (maybe, CD) because it has independent volume controls for right and left channels. This means that you virtually have balance control as well.

Second, I love its sound: it's clean, open, detailed with a nice soundstage. It sounds as nice as my Nikko Alpha II. Maybe, its power isn't enough for some "greedy" speakers, but it will be enough for most speakers available on the market.

Third, it proves my belief that so-called "high end gear" doen't mean gear that sounds really good, at least musically. I don't know about "other" kinds of pleasure such as luxury, status symbol. Before checking this out, I owned a Classe CAP-80. That's an audiophile unit which receives a number of favorable reviews from audiphiles. I went by reputation, and spent $650 to get it. After testing a vareity of configurations with a few speakers from Rega Model 2 to Aegis 3 to Cabasse Galiote, I concluded it didn't deserve the money I spent on it, and sold it: to be honest, it sounded worse than Audio Innovations Alto which cost me $280. Now, Alesis RA 100 came to my home and proved the correctness of my conclusion. No comparison: CAP-80 didn't deserve the 1/3 of Alesis in terms of sound quality.

A few complaints on RA 100. Power handling info is misleading. Many ad say that its handling is 100W but it's into 4 ohm per channel, and how many people reading reviews at this site are using such speakers?? It is more helpful to state that its handling rating is 50W into 8 ohm.

Another problem, probably specific to my unit alone, is that it makes a low buzzing noise while it's working. It's not so obvious but it gets noticeable sometimes.

Conlusion. This product is highly recommendable. If you're lucky, you can get this gem for less than $200 on eBay. With this, why do you still need audiophile amps priced over $1000? No way. Spend $800 to get real speakers.

Similar Products Used:

Classe CAP-80, Nikko Alpha II

Give this amp a try!!! There is no other amp that comes close! True power from a little rack mount unit (3 space). 100 watts at 4 ohms or 50 watts at 8 ohms, this little guy has giant heat sinks that eliminate the need for any additional noise producing fans. Mine has been powered up for nearly two years now with no glitches to report. If you're building a project studio, or just getting into "separates" go to your local music store and give this guy a listen!