Hello, folks,

I am trying to decide on what pre/pro to go with the Emotiva LPA-1 amplifier.

I sent the LMC-1 back because of hissing, or what I call "ffffffffffffffffffff."

I have a Yamaha 661 (no hiss) that I am trying out, but I feel like since I have an amp, I can get something cheaper that will do just as well and use the money for some CDs and movies. Even if I do want the 661, I can get it for $150 less online.

I don't want suggestions for brand, and this is not a "$300 avr will perform just as well as a $5k processor" issue. But is there a certain spec I need to pay attention to in order to take full advantage of my amp? A guy on avs talking about using an AVR as a pre/pro was saying: "My only concern is output impedance of the receiver and its ability to drive the amplifier to its full potential."

Thank you all,

Rodney, there's little need to be concerned about any performance specs of modern receivers when they're being used as pre-pros. The output impedance, which was mentioned on the other board, is typically a suitable value(e.g., about 100 to 500 ohms)and unless the gain of the separate amp is unusually low(e.g. less than 25dB), the output from the pre-outs is typically plenty to drive it to full output.

What are relevant factors are the features that you want in a receiver/pre-pro, beginning of course with a full set of pre-outs.

Thanks, John.

I'll be doing some searching in the next day or two and hopefully come up with something in the $400 range.

Since you answered, and since you think that in blind tests people wouldn't know which is which between the $$$ and the $ processor: is it true that there is such thing as better DACs than others? And aren't the DACs the major part played in a processor?

Thanks again,

Yes, that's part of the picture, but as Alan and others have pointed out, DACs are now a mature technology. The small differences in measurable specs that remain between different chips don't result in audible differences. Excellent DACs which exceed the needs of human ears and the digital material which they process are available from several makers, and in the large quantities which equipment manufacturers buy can be had for about $1 each.

I, too, have been looking into this option. I do think I will wait until I can get something with HDMI 1.3 and the new codecs for HD DVD / Bluray, but in my searches, I have found that a good, used Outlaw Audio pre/pro is a great idea.

Check 'em out at www.outlawaudio.com

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Since you answered, and since you think that in blind tests people wouldn't know which is which between the $$$ and the $ processor: is it true that there is such thing as better DACs than others? And aren't the DACs the major part played in a processor?

Thanks again,

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Yes DACs make an audible difference and are a key contributer to the sound quality of the device. Like all audio component parts, quality will vary. If you are buying a processor, receiver, cd or dvd player, it is worth your while to research what DAC and ADC chips are used much like when you are buying a computer. Look for names like Burr Brown, Sharc, Wolfsen, and Crystal. DACs used in receiver/processors, dvd and cd players contribute significantly to their ability to reproduce sound accurately as do the quality of their power supplies.

Good DAC design keeps noise/distortion to a minimum, preserves dynamic range, and faithfully converts the digital signal to analog without introducing unwanted artifacts or dropping data. There are well accepted performance parameters associated with DAC chips such as better signal to noise ratio, dynamic range and channel isolation or crosstalk (much like in an amp). Like all computer chip design it is not a static area and not all chips funtion the same way.

While it is true and beneficial that the price of DACs continue to drop, it does not follow that they are all equal. Its not so much whether a chip is worth a dollar or a dime, rather its how well it is spec'd and implemented into the overall design. In blind tests that I have been involved with the differences are audible among processors and players depending on where the DAC is taking place, though it becomes much more subtle with better equipment.


There is a view that a DAC with 20bit resolution and 120db SNR is at the limit of audibility so DACs with much better specs are unnecessary, but I believe those two specs don't tell the whole story.