Dual Channel Laboratory Amplifier
The DC-300 is a dual channel, high power amplifier for precision amplification of frequencies from DC to 20KHz.
The unit features extremely low harmonic and intermodulation distortion, very low noise, highest damping factor, and quality parts and workmanship.
Because of the large output power, it is possible to obtain a monaural 70-volt balanced line without using an output transformer.
Power output: 155 watts per channel into 8Ω (stereo), 310W into 16Ω (mono)
Frequency response: 1Hz to 20kHz
Total harmonic distortion: 0.05%
Damping factor: 750
Gain: 26.3 dB
Input sensitivity: 1.75V
Signal to noise ratio: 110dB
Speaker load impedance: 8Ω to 16Ω
Dimensions: 19 x 7 x 9.75 inches
Finish: satinized front panel, grey suede lexan insert
If you have any problems opening files please read the download FAQ. All files are provided under strict licence and reproduction without prior permission or for financial gain is strictly prohibited.
If you have additional documentation please consider donating a copy to our free archive.
Reviewed Feb 18th, 2016 by John Buckham
Good Clean Sound and Plenty of it! That's been my mantra for Crown amps for years. The DC-300 is a basic, well made basic power amp intended for commercial applications, but will find good use in home entertainment systems as well. This amp is intended to be rack mounted, it can also be mounted in Crown's available at the time wooden furniture cases. You get two unbalanced quarter inch input jacks, two speaker binding posts, two attenuators on the front and a power switch. The input sensitivity is intended for commercial applications requiring (at least in my case) 1.4 volts to generate full output of 150 watts plus per channel.
Objectively on paper and lab tests show the original DC-300 to exhibit very low distortion and noise numbers, which the unit does. Subjectively some listeners may feel the audio lacks snap and sparkle. The sound stage may seem shallow and narrow to some. The speakers and to a lesser extent the pre-amp has some effect on the listeners perception.
One must realize that when the first DC-300 was introduced an amp of this power was unusual. Crown did the best they could with the silicon that was available to them at the time, but later editions of the DC-300 have improved the sound stage tremendously. The end of the line for this series was the DC-300A 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-300 before you put it in use the massive computer grade filter capacitors should be replaced, if not already done. Also clean the attenuators on the front panel and run it though a complete QC test (Power out, IM, THD +N, S/N) to make certain the amp is performing to spec. Many of these amps were mounted in racks and left running in commercial installations for years and years...these amps incredibly reliable and to see a 20 year MTBF in the real world is common.
to close on this - if you want a DC-300 in your audio system depending on how discriminating you are, looking for a DC-300A Series II may be prudent. You should plan on reconditioning an original DC-300 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-300 amps
exhibit a mechanical hum from the power transformer. It's not too loud but in a quiet listening environment bay be distracting.
Reviewed Sep 25th, 2015 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, 2013 by j0hnh0dg
I have had a large number of these amps as well as the original DC300. 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 400 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. I prefer the silver faced ones before the FTC regulations came along. I think that there were modifications made to pass these regulations that weren't the best sonically. I feel the Power Line 4 / PS400 was an excellent upgrade to the DC300A without losing any of the DC300A's good points, and I use one of these for listening.
Reviewed Sep 29th, 2013 by Rusaf
I bought two of these in 1979, and both are running strong at 34 years young. They do a stellar job with the hifi, and make great dc power supplies. They were my next jump from a pair of Crown D-60 amps, which I also still have. I'm a newbie here; if I figure out where I can do this, I'll post the whole audiophile system I built, starting in 1975, but in earnest in 1977.