That's why I said that if you can get one cheap and use it in a non-critical listening situation then go for it. I would much rather listen to a Bryston amp than the Crown. I just wouldn't expect the Crown to be the best choice for someone who wants an amp for critical listening in their main system. I think that if you did this then you would probably be back looking for another amp in a couple of months. Yes, the Bryston amp I have sounds better than the Crown amp I have. The DCA II is a classic amp design of the 's, and was used widely by pro's all over the world.
A workhorse. Few other amps could withstand the constant and often abusive treatment they got. I saw a few blown-up units, but not nearly as many as other brands. So they are well built, as I said previously.
Also they have quite a good amount of raw power, watts per channel, this can have a quality of it's own when listening to lowef speakers, or at elevated SPL. Of the two, the Bryston sounds nicer to me. That's my opinion. It's not a colossal difference, but it's there. I use the word "harsh," other's use different words to describe sound, that's OK.
I have heard the CDA II through many decades of pro studio work here in Los Angeles, they were in several other studios during the 's. I could hear a similar signature to the sound of both the and my DA series II, solid in the bass but a little harsh near the highest octave.
Not a bad amp in it's time, but can be beat by today's great designs now IMHO. Many will find this amp perfectly good, and they are quite fine, just not the very best sounding amp IMHO today when competing with many audiophile amps of good quality. Or the Bryston unit I own. This is my opinion.
Thanks, R. Location: Philadelphia, PA. The DC II was paired with a Hafler DH in an amp rack which I normally used to drive stage monitors, or in a very small club I would use half for the performer's monitor and the other half for the house. Don't think I'd use a DC for a full range system. The difference, as it turned out, was a function of the particular loudspeakers the DC was used with. There's not really much more to be said about its sound, because the DC appears to be entirely without any sound of its own.
And if we have ever said this about any other previous power amplifier, it is only because we had never heard the DC But it does raise a question which we are not sure we want to try to answer just yet. Namely: Have we been doing some sort of a disservice to some loudspeakers we tested in the past, by not testing them with the DC?
Would some systems that were faulted for booqy bass have sounded satisfactory with the Crown? Certainly, we can justify our mistaken? But the question remains: Should a loudspeaker be judged on the basis of its potential performance, or on the basis of its performance under what might be considered "realistic" conditions of use? Perhaps both approaches are in order, but as we said, we won't try to decide now.
It is obvious that, on the basis of price alone, the DC is not for every home-hi-fi hobbyist. And for those who can afford it, it is not without potential problems.
For example, it is one of the few available power amplifiers with power enough to devastate most loudspeakers.
You may think you can avoid trouble by "being careful," and you probably can for a while. But if two 5-cent fuses can buy peace of mind, they're worth it. Recommended fuses are listed in the instruction manual. Follow the recommendations. An Honorable Mention The manual, by the way, deserves an honorable mention, too. This was obviously written by engineers for engineers, and while the sections on installation and use are clear enough to be of value to the average nonsophisticated hobbyist, the rest of the manual provides just about all the information that any user could conceivably need.
To the hi-fi buyer accustomed to the usual consumer-type instruction manual, this one will be a revelation. The manufacturer claims that the DC is "protected against all the common hazards which plague high-powered amplifiers," and as far as we could determine, this was the case. The manufacturer warns that damage can and will occur if the two "hot" output terminals are connected together, but this is not at all likely to happen accidentally.
Ve tried all the usual accident-type things in an effort to get the amp to self-destruct, but it didn't. When presented with an impossible situation, it just shut down temporarily or popped a fuse. The DC's distortion is low enough to expose to the Nine's unsurpassed transient response, it appears to be completely stable with the Nine's highly reactive loading, and its power capabilities are a perfect match for the Nine.
A single pair of Model Nine panels have a nominal 16 ohm impedance and a power capacity of W per panel. The DC will deliver almost exactly W maximum per channel into a 16 ohm load, and when two KLH Nine panels are paralleled in a four-panel system, the resulting 8 ohm load allows the amplifier to deliver almost Wpc, which is still close to the rated capacity of the speaker system. Consequently, no protective fusing is necessary with the Nine, although it is necessary to add large isolating-capacitors to the speaker lines to prevent the Nine's step-up transformers from shorting out the amplifier at subsonic frequencies.
Issues Unlike many solid-state power amplifiers, the DC produces no click or thump when turned on, which is nice in view of its destructive capabilities. Some preamplifiers and tuners do however produce loud switch-on pops, and a few of them the Dyna PAT-4, for example will pop if the input selector switch is operated during the first several seconds after switch-on. For this reason, even if the loudspeakers are fused, it is a good idea to turn on the preamp and tuner first and then wait a few seconds before turning on the DC This could save you some money on fuse bills.
An even better idea would be to install a time-delay relay between the DC and its controlled switched outlet from the main control center. The Amperite N with a second delay and 5A capacity would do it.
The input impedance to the DC is quite low compared with that of most power amplifiers. With the input level-sets the front-panel knobs half-way up, the input impedance is around 50k ohms, and this drops to 10k ohms with the controls up full. And since the amplifier's gain is about average, the controls will have to be all the way up unless you're driving highly efficient loudspeakers, so it is wise to check for compatibility with the preamplifier you plan to be using.
Most solid-state preamp lifiers will work into 25k ohms or more, and have enough reserve gain and enough clean output to allow the DC'S input level-sets to be run at the appropriate position.
The instruction manual, incidentally, shows curves for input impedance vs level-set adjustment. Power The most obvious question about the DC, though, is likely to be "Who could possibly need that much power?
And the DC sounds bet ter than any lower-powered amplifier we have ever heard, even at very low listening levels. Whether or not the high cost of the DC is worth the difference to you depends, first, on how your particular loudspeakers will respond to its ministrations as mentioned above , and second, on how much any sonic improvement is worth to you personally.
Even apart from its sound, the DC is built like the proverbial battleship, with the kind of attention to detail that makes all professional-type equipment seem so outrageously expensive until we find it still operating 20 years after the "competitively priced" audiophile equipment has succumbed to chronic parts disease.
Conclusion Summing up, then, we would venture to say that this is the best power amplifier that is currently available, regardless of cost. We will even go so far as to guess that it will not be possible to build a better one, although we have some times been proven wrong on some similarly rash statements in the past.
One thing we are quite certain of, though, is that this amplifier has spoiled us. After the DC, any other power amp will be anticlimactic. We won't hold our breath! Gordon Holt Manufacturer's Comment The power output capabilities of past and present power amplifiers have been based, not on acoustic requirements, but on electro-economic considerations. Today's low-efficiency loudspeakers in a room of typical size would require several kilowatts of input power in order to produce dissipation allowing the greatest sound-pressure peaks that can occur in live musical performance.
Clearly the larger the amplifier, other things being equal, the more faithful the sound. By delivering the maximum output power reasonably obtainable with today's semiconductor power technology, the DC delivers a previously unattainable level of fidelity. Since it is inevitable that a power amplifier smaller than several kilowatts will be overloaded from time to time when driving low-efficiency speakers at high volume, overload recovery must be instantaneous and free from subsequent thumps or distortion.
The DC's totally DC-coupled design is unequalled in this respect. Dynamically, the DC is, as far as we know, without peer. Its ultra-low distortion required the development of an ultra-low-residual IM meter less than 0. Harmonic analyzers are not sensitive enough. The oommon practice of measuring IM down to no lower than 1 watt is not an adequate test for crossover notch distortion, as large amounts of IM are often produced between 10mW and 1W, while distortion above 1W is acceptably low.
It is the DC'S extremely low distortion below 1W, plus its very low hum and noise, that make it sound so outstandingly good at low listening levels. Incidentally, its noise is so low typically dB below W into 8 ohms that special voltmeters having a full-scale sensitivity of microvolts had to be built in order to allow meaningful production-line testing of the amplifier.
The end of the line for this series was the DCA Series II, which is a quantum leap in sonic quality over the original and should please most if not all audiophile listeners.
If you obtain an original DC before you put it in use the massive computer grade filter capacitors should be replaced, if not already done. Many of these amps were mounted in racks and left running in commercial installations for years and years You should plan on reconditioning an original DC if not already done so before you pass any judgements as to it's sonic quality and accuracy. One last item, some of the DC amps exhibit a mechanical hum from the power transformer.
It's not too loud but in a quiet listening environment bay be distracting. Happy listening. Reviewed Sep 25th, by jumpstartbill. Best solid-state vintage amp if you ask me. Nice warm sound. Be careful running into 4 ohm speaker loads. Had to replace the sub-woofer in my Infinity speakers cause of this. Helpful to know your way around a circuit, as the output caps on the heat sink will invariably need changing out.
Transistors close to the heat sinks will also tend to blow. A rack fan will eliminate most component problems. Reviewed Nov 11th, by j0hnh0dg.
I have had a large number of these amps as well as the original DC The only trouble spot I have consistently found are the capacitors in the voltage doubler, they get cooked by the large resistor and 2 transistors next to them. I have shorted them, driven motors with them, tested many experimental speakers, and you can imagine how stupid the wiring gets by 3 in the AM , they have been the Hz supply for aircraft equipment with an oscillator and a step up transformer, and yes they have been used for listening.
They are hard to kill. But how do they sound? Quite variable.
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