Pro vs. Consumer Equipment

Thorman is right on the money. Most of that stuff sounds horrid unless you're looking for sheer brute volume. This is due to the fact that these amps are not built for sonics, they are built for rugged reliability under any / all load and thermal conditions. They are the type of amps that give SS a bad name and should be avoided unless you simply need high spl's and / or gobs of power. Sean
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PS... I've not heard EVERY "pro" amplifier, but i've worked with enough to know that i would NOT want to use them at home. At least not as a "full range" amp.

While i've never heard the ART SLA-1, i read as much about it as i could find on the net. From what i can tell, it is pretty much the same thing as their DIO dac. That is, ten pounds of parts crammed into a two pound box.

In order to obtain the power output that they are and not run into thermal problems, the amp has to be biased quite low. There just isn't any heatsinking / chassis that would allow a higher level of bias. If it was biased higher, the amp would be going into thermal shutdown on a regular basis. As a general rule, low bias amps tend to sound a lot less refined, lack black backgrounds and do not offer the amount of "air" that a good high bias amp can offer.

On top of this, the power supply has to be compromised for the same reason i.e. small chassis size. There just isn't enough room to get a good sized transformer or filter caps in there. To prove / support this point of view, the amp is rated at 100 wpc @ 8 and only 130 wpc @ 4 ohms.

The logical deduction to all of this is that the amp would lack bass impact, definition and control. I would also expect it to get noticeably "smeary" as drive levels were increased, moreso as the impedance of the speaker were dropped. This all has to do with the lack of available current with limited power supply reserve.

While i know that i've not heard the amp and some of you are probably rolling your eyes / saying what a "dork" i am for jumping to conclusions, you just can't get around the basics of good amplifier design without some phenomenally fancy circuitry being required. Since phenomenally fancy circuitry typically requires a lot of R&D ( research & development ), the end result is typically a product that is quite costly to bring to market.

Given the price / size of this unit and the rated power output, it is probably nothing more than a cut-corner design that takes up minimal space. It was probably built to a price point ( i would assume VERY much so ) and to suite the non-demanding nature that one finds driving small monitors listened to in near-field fashion in a studio. In such a situation, volume levels are never real high and the amp doesn't have to control a large driver with a lot of reflected EMF being generated. As such, it probably works fine for the market that it was intended for ( after all, Studio Line Amp is the name ) but would not be suited for a true "high fidelity" system. Sean
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I'd like to see if this piece lives up to the hype or if it is another case of the "Emporer's new clothes" syndrome. Personally, i thought that the ART Dio DAC was a perfect example of hype. Given the fact that this is a product from the same manufacturer and one of the main instigators of the "internet hype" is a person that could benefit from increased sales of these units ( much like those that "hyped" the DIO and performed mods to it ) really makes me leary of buying one to find out for myself. Sean
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I agree Forever. Active multi-amplification and / or much simpler crossover design goes a LONG way in terms of what we hear from a system. That is primarily why i'm a "fan" of active crossover / mulit-amping and / or "true" full range single driver systems. Both get rid of ( or minimize ) the passive crossover networks and increase dynamics and transparency. It would be a "win/win" situation for home use if higher costs and greater complexity were not involved.

As far as Pro speakers go, most have very drastic flaws but do what they are designed to do quite well. Then again, the same goes for most well thought out home speakers. The two situations are VERY different from each other and the products are built to suite those individual needs. Sean
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Abex: The Dio that i listened to was modified by Wayne and made use of an outboard power supply of measurably higher current than the stock offering ( 3 amps continuous ). This power supply should have allowed the Dio to produce a lower noise floor due to reducing noise generated by the transformer itself and offering the potential for improved dynamics. Even with all of this, i was not impressed with this unit in the least. Nor was my brother. I would rather listen to a Pioneer DV-440 24/192 DVD player than use a Dio in any of my systems. I know that this sounds "extreme", but i'm being 100% truthful here.

We A/B'd the Dio against the stock DAC's in the Pioneer and the Pioneer was far less boxy / offered much greater space, air, dimensionality and center-fill to the soundstage. This is not to mention that the Pioneer produced a blacker background. In comparison, the Dio sounded dull, compressed and 2 dimensional. The sound literally seemed to "cling" to the speakers and refused to spread out.

When all was said and done, putting the Dio into this system was like taking two steps backward in both my and my brothers' opinion. We tried three other DAC's ( one purchased used for $150 used, another for $200 used and another for $300 used ) within the system at the same time and the Dio was the worst of all four methods ( including using the stock Pioneer DVD player as a one box ) of reproduction. For the record, all of the other DAC's sounded better than the Pioneer by itself. Bare in mind that this Pioneer DVD player was available brand new for $149 from Best Buy. Comparing something like this to a modified Dio should have been a "no brainer". Either this specific modified Dio was a "dog" or i have to wonder as to what other people think is "good". Personally, i wouldn't even use a Dio ( modified or not ) as a door-stop. That is, based on the experience that i had with the specific unit that i tested. Sean
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