Thank you. Is there any test and measurement on the internet of the 3400? I didn't find any
I couldn't find any either (except the very basic type, more later), but if you compare the block diagrams and schematics of the 3400, 3500, 3600, 4400 through 4700, the preamp dac circuits are bascially the same, except the 3400,3500 has only 7 channels. The DAC, Volume control, opamps, that largely determined the overall distortions will therefore be very comparable, but the 3600 and newer models will have the following advantages:
a) better layout, noise is expected to be a little lower. The 3400 and the 3500's is virtually identical in the audio circuitry, parts and layouts.
b) slightly larger power transformers (very little practical difference, you need 2X the power output to gain 3 dB of sound pressure level.
c) apparently has resistor with better tolerances (according to bigguyca, not sure if he is an insider who has the intimate knowledge).
d) models 3700, 4700, 6700 has the preamp feature, that allows you to disconnect the preamp outputs to the power amp outputs (I know you already know this).
e) the 3600, 4300, 4400, 4500 do not have preamp mode, but there is a cheat that you can do, that is, use the amp assign function to disconnect the front left and front right preouts to the power amp inputs.
d) and e) will not make a difference in terms of pre outs THD+N unless you need voltages >= about 1.5 V.
Also, regarding d) and e), even without disconnecting the power amps, the pre outs can still output higher than 2 V and maintain SINAD of about 75 dB, that is THD+N or about 0.018%, 0.1% is the level of what is generally considered below the threshold of audibility. Consider this, 75 dB SINAD at 2 V is about the same performance as the Marantz AV7705, 7706, 8805 and 8805A that are preamp processors that don't even have internal power amps, so I don't think people have to worry about the lack of preamp mode, though it is clearly a great feature to have, just saying that for audible benefits, there may be very little or nothing to gain depending on your application.
There are no detailed reviews on the AVR-X3400H such as Amir's but there are some very basic bench test measurements by Soundandvision.com:
Test Bench Two channels driven continuously into 8-ohm loads: 0.1% distortion at 123.0 watts 1% distortion at 147.6 watts Five channels driven continuously into 8-ohm loads: 0.1% distortion at 97.6 watts 1% distortion at 106.1 watts Seven channels driven continuously into 8-ohm loads: 0.1%...
www.soundandvision.com
If you look at the distortions+noise vs measured output level, it is still hard to beat, just compared it with the NAD that costs a lot more:
You can see that it did less than 0.01% at it's rated output into 8 ohms. That is consistent with Amir measurements. To achieve such low distortions at the power amp output, you can imagine that the preamp performance has to be much better too.
According to the reviewer:
This graph shows that the AVR-X3400H’s left channel, from CD input to speaker output with two channels driving 8-ohm loads, reaches 0.1% distortion at 123.0 watts and 1% distortion at 147.6 watts. Into 4 ohms, the amplifier reaches 0.1% distortion at 145.4 watts and 1% distortion at 176.6 watts.
Now take a look of the NAD that also costs more:
Amir also measured the NAD, and had similar results as soundandvision.com
You can see that the NAD has much higher distortions at just about any output level, yet most of their owners will tell you it sounds great. The fact is, how good an AVR would sound to you depends a lot of:
- your preference, that is subjective.
- quality of the media contents, that is recording/mastering.
- speakers.
- room acoustic conditions, use of room correction such as Audyssey, Dirac Live, Anthem ARC, Trinnov, YPAO..
- media player.
Distortions? Probably not too much once it gets close to the level of something like 75 dB SINAD, or 0.018% THD+N, though if noise is the main contributor then you may hear hiss and/or hum if your room is very quiet.