[avahifi]

AVA does not normally publish specifications, inasmuch as any old audio piece from Walmart will have excellent published specifications and in general, the numbers don't predict how well the unit will perform musically in your system, not until we get a much better set of criteria to measure and understand.

However, just for fun, here are a few AVA numbers I came up with today while playing at the bench.

Insight SL preamplifier line circuit frequency response (measured at 3V peak out into a simple 100K ohm load):  -3dB at 500KHz and 3Hz.  Output noise with shorted inputs, about 1mV.

Ultra Double 550 amplifier frequency response, both channels driven into 8 ohm loads at 60V peak out:  -3dB at 150KHz and 5Hz.  Output noise with shorted inputs, about 2mV. Boy does that 3Hz near full power make the table lamps on the bench flicker!

Just something to talk about.

Regards,

Frank Van Alstine

[oneinthepipe]

Frank:

I don't want to be an overeager contributor, and as you know, I know nothing about audio, but just to test my ignorance, with the patience of the other forum members, I believe these specifications indicate that these components have the capacity to reproduce signals across a wide range of frequencies without losing power, which would be related to their capacity to faithfully reproduce music with broad dynamic ranges, and that these components have an extremely low "floor" noise, which would enable the listener to hear the music without a lot of extraneous hiss, noise, etc.  I know that other manufacturers list their components' frequency responses, but I don't recall other manufacturers listing their components' output noise.

OITP

[turkey]

Frank:

As you know, I know nothing about audio, but just to test my ignorance, with the patience of the other forum members, I believe these specifications indicate that these components have the capacity to reproduce signals across a wide range of frequencies without losing power, which would be related to their capacity to faithfully reproduce music with broad dynamic ranges, and that these components have an extremely low "floor" noise, which would enable the listener to hear the music without a lot of extraneous hiss, noise, etc.  I know that other manufacturers list their components' frequency responses, but I don't recall other manufacturers listing their components' output noise.

OITP

Well... they may be wideband, but all we know is that they're wideband into resistive loads. Let me know when you buy some 8 ohm power resistors to listen to.

The noise specs are quite good, which is born out when AVA equipment is used with efficient speakers (as I have done for the last 2 weeks). There is really no noticeable noise from the AVA equipment when listening at reasonable distances. (You can hear some hiss if you get really close to the speakers.)

[mfsoa]

VAC has some residual noise specs on their web site.

I see 0.7 mV for the preamps and amps after a quick look.

Don't know or care if it was measured in the same way as AVA.

-Mike

[Minn Mark]

Not sure if on the same page as you guys, but with my Magnaplaners (not such an 'easy load'), I hear no noise from my AVA equipment, unless I turn volume up full with no input signal. I can hear some hiss, then.

I can also share that when I use my all tube 35w class A grounded guitar amp (Savage Audio Electronics Glas 30--shameless plug) on the same AC circuit as the rest of my electronics, I get no contibuted noise in either direction (amp to stereo, or stereo to amp).

Keep rockin'

Mark

[warnerwh]

It may be that some people think that you are hiding something or your specs aren't up to snuff with comparable cost components when they're not published.  Specs can serve as a rough guide. One thing I still look at is s/n ratio.  If it's under 90 A weighted on a pre, amp or dac I'd approach that component with caution. In actuality 85 should suffice. I've talked to others who've been in the hobby for some time saying that is one spec they do look at.

Overall publishing some basic specifications would help sales imo. Power at 8 and 4 ohms, frequency response, s/n could help. I think having reviews, either commercial or user, and statements as to the sound helps too. Many people need others opinions as it makes them more comfortable with their purchase. For sure the Fetvalve amps need more information than just specs anyway. As a matter of fact if I didn't have to I'd never sell the 550 I have because it's the best amp I think I've ever owned. The general audiophile consumer is more inclined to buy more main stream flavor of the month gear and you don't spend a ton of money on advertising which will get your company rave reviews that sell components.

You've been successful for a very long time and that says a lot. Maybe you should try it for a year and see what happens. It shouldn't hurt sales.

[Wayner]

While specs are a nice comparison tool, no-one measures the same. Congress pass one law regarding power amplifier specifications so they should be stated X amount of watts RMS per channel, both channels driven with X % harmonic distortion. But sellers have found ways around this and the mobile industry completely ignores these RMS ratings.

Until the industry adopts a uniform code for specifications and mandates how the tests are done, they will be used as propaganda by many companies. After all, the consumer has no way to verify. Also, some amplifiers is AB mode can have higher distortion values in lower output levels and less at higher output levels, where on-one listens (way to fricking loud) to make any difference.

Wayner

[boycephoto]

Wayner,

Your absolutely right.  So why even state any specifications, other than the physical weight.   Just describe AVA amplifiers as SMALL (Ultimate 70)  Medium  (Insight 260)  Large (Insight 440H)  and X Large (Ultra 550) to specify the  power each amplifier has.  Also, I have never listened to my system and thought the THD or IM distortion was to higher than the mfg. stated specification!   

My opinion, I would like to see a 4 ohm power rating, some amplifiers double their 8 ohm power rating @ 4ohms, yet some don't change at all, same with the 16 ohm output, as I have 4 ohm Magnepans and 15 ohm Rogers.  Maybe I am the odd ball. 

I hope everyone stays dry and warm this weekend in West Mn and ND.  Good Luck!

Dave

[markC]

Don't forget Winnepeg!
Staying close to double the power output at half the load is a sign of a solid power supply. e.g 100W into 8 ohms, 190W into 4 ohms. Specs are manipulated for sure, but true RMS is true RMS. And the mv noise is a tangible spec.

[JerryM]

Insight SL preamplifier...  Output noise with shorted inputs, about 1mV.

Frank,

What are you using as input shorting plugs?

Thanks,
Jerry