This is a review and detailed measurements of the Marantz SR7015 "8K" 9.2 channel Home Theater Audio/Video Receiver (AVR). It was purchased new and kindly sent to me by a member. The SR7015 costs US $2,300 from Amazon including Prime shipping.
Not much to say about the design of the SR7015 as it looks like Marantz AV products for years back:
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Sorry for the tape. I try to keep test unit as close to new condition as possible so did not take it off and operated the unit using its remote.
Here is the back connections:
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I sent the measurements you are about to see to Marantz (part of Sound United) and they were kind enough to confirm that they agree with their testing.
AVR DAC Audio Measurements
As usual, we start with our dashboard testing the internal DAC using pre-out on the AVR. I run this test two ways: with the amplifiers on and off. Leaving the amps on usually causes them to clip and drag down the performance of the pre-out:
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You can see signs of the amplifier getting unhappy with very high harmonic distortion content. I put the unit in Pre-amp mode (in Amp Assign submenu) and these were the results:
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While we get a 5 dB improvement in noise and distortion, the SINAD which represents both is still a very disappointing 80 dB. This drops the SR7105 in the bucket of "poor" performance with respect to AVRs and DACs tested:
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Denons using similar architecture are far better and indeed class leading in my measurements as you see above.
Sweeping the digital samples to see where the optimal output level is for this AVR we get:
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We see that the optimal output level is around 0.7 volts which is quite low. If you are buying an external amplifier make sure its sensitive is no higher than 0.7 dB or you will suffer from degradation of the internal DAC and buffer stage in SR7015.
Notice how having the amp on and off makes little difference until you approach 2 volts. The degradation is a function of the buffer/gain stage of the unit. I have indicated the volume level where this degradation occurs (73). So if you are at or below that, you would get significantly better performance (approaching CD's 16 bit dynamic range).
Testing the DAC reconstruction filter shows the same disappointing slow response we see in other Marantz AVRs and Processors:
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The consequence of this is that if we allow wider bandwidth for the test, THD+N/SINAD suffer greatly compared to the dashboard which uses the audible band:
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Further evidence is in spectrum of a 10 kHz tone:
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We see the usual harmonic distortions at multiples of 10 kHz but also very tall spikes at the 10±44.1 kHz as indicated. You won't hear these fortunately but technically it is is not nice to have them.
Another disappointing area is jitter:
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We tend to think "bits are bits" but clearly the analog output of the unit is impacted depending on which digital source we use: HDMI and Coax. Each has their own induced jitter components which shows lack of design hygiene in producing a clean clock/reference voltage. Fortunately once again audibility is not a problem as levels are quite low.
Linearity is OK for an AVR (but poor for even a cheap desktop DAC):
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Exponential rise typically indicates noise intruding in the measurement even though I highly filter the output of the AVR for this test.
Finally, 32-tone signal simulating "music:"
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AVR Amplifier Measurements
I prefer to use analog input for my amplifier measurements because we can then compare the amplifier performance with that of stand-alone amps. But I need to make sure the analog input is not digitized or subjected to other degradations. Fortunately such is the case here if you don't use any digital processing or use Pure mode. Here is analog input:
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And Coax:
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Typical of other Denon and Marantz, overall control of distortion and noise is very good:
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And well above average compared to 120 or so amplifiers of all kinds tested so far:
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So the rest of the tests will be with analog input starting with frequency response:
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And signal to noise ratio:
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That's decent result.
Here is power into 4 ohm:
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And with allowance for higher distortion and burst power:
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And 8 ohm:
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Testing for frequency sensitivity across full power spectrum we get:
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For a class AB amp, I like to see tighter clustering of the graphs indicating less sensitivity to frequency. As it is, performance drops fair bit at 5 kHz and higher.
Conclusions
Like clockwork, the performance of Marantz SR7015 tracks other Marantz AVRs we have tested. They take the excellent platform used in Denon sister products, and modify them to produce objectively worse performance by good bit. Distortion is sharply increased and extremely slow DAC filtering causes lots of ultrasonic noise, making any intention of playing "high-res" audio moot. Company feels subjectively the modifications improve the sound of the unit. With no controlled listening test demonstrating that, and measurements showing the opposite, I don't think the changes are wise or merited.
Needless to say, I can't recommend the Marantz SR7015. I highly suggest you stick with the Denon counterparts instead.
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As always, questions, comments, recommendations, etc. are welcome.
We thought we enjoy the fruits of our labor by making eggplant parmigiana using the tomato sauces we had canned and peppers we had frozen:
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Oh man did that come out great! The flavor was so much better than canned tomatoes. Had not two, but three helpings of it!
It was also so quick to make given the fact that the tomato sauce was already reduced during the canning process.
Still recovering from shock of expenses for last year so
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