Originally Posted by batpig
I'm so confused. I don't even understand what you are pissed off about.
Yesterday at 5:14 pm
The AVR4520 has serious flaws as an audio equipment that vendors (in the forum) do not want you to know;
1. The power bypas capacitances of the its DACs are way below that is required. Result is that sounds from digital sources will invariably be grainy. Increasing the capacitances to the level recommended by Texas Instruments improves the results DRAMATICALLY. That is if the AVR4520 is used as a pre-pro only.
2. The analog signal amplification chain of the AVR are never buffered. Analog signals go straight to the volume control chip without buffering or impedance matching. All signals coming out of the volume control chip also go straight out to the pre-out for extenal amps or its internal amps.
3. The internal amps of the AVR4520 use UNbuffered, single-sided voltage amplification section (VAS). Also because of this unsophisticated circuit, the AVR4520 uses transistiors that are known to be "noisy". They had to because the VAS, being single-sided, needd transistors that can handle the full voltages used. Up to now I am not aware of any "audio" VAS-duty transistors that work at those voltages. Good ones can be used at those voltages only in buffered, cascoded, and/or double-sided VAS circuits so each transistor work only with half the voltages, at the most.
The AVR4520 is not the kind that uses the more sophiticated "audio circuits" that buffers/fortifies the signals along the signal amplification chain to ensure effortless, clean, and undamaged signal.
Except for some parts that are good for"advertising" the AVR4520 uses the cheapest components parts - from the boards, interconnects, capacitors, and op-amps.
These flaws are the norm for the CHEAP kinds of receivers, not for the kind of receivers priced around $2-3k.
The internal electronics (and, subjectively, sound) of the AVR4520 is of the kind that is generally described or characterised as CHEAP and FUNCTIONAL - in short, utilitarian - the same kind as that of a pocket AM radio.
It is not hopeless, though, if you are capable of DIY fixes.
The AVR4520 can be salvaged into a good pre-pro if 1) the DACs and ADC circuits are brought up to the level recommended by the chip makers, and 2) buffer the analog signals coming into and going out of the volume control circuitry, and optionally 3) replace the cheap capacitors throughout the audio signal chain - then you have a good pre-pro.
I would say, however, that the internal amps of the AVR4520 are hopeless. The boards of the amps are of the lowest quality that they wont survive the necessary modifications to the I/P, VAS, and O/P stages.
You should (if you haven't yet) ask the forum members' honest opinion about the AVR4520's suitablity for MUSIC- not HT.
HT does not really need the SQ from "music or audio-grade" electronics.
Yesterday at 6:53 pm
Out of curiosity, what product would you suggest?
Yesterday at 8:58 pm
I am sad that my message did not reach you in time.
Because the technical documentation of these electronic products are not readily available until their "end-of-marketing-life" I cannot recommend anything except:
1. to suggest to you to do more research so you be more equipped to "read-between-the-lines" of what people in the forums are saying. Vendors with vested interests populate these forums - so be careful. If the vendor says his unit sounds perfect in his HT, but admits that he is not really into music ...
2. Based on technical documentations of older products (of similar class) that I had the opportunity to study, I would describe some brands as follows:
You will get what you pay for - not a rip-off like the AVR4520. Cheap Yamaha units also have cheap electronics inside. Premium models also have "premium circuits" that would bet as good as the best in their price range. Yamahas in the price range of the AVR4520 would be infinitely better than the AVR4520.
Marantz and Denon:
They use inconsistent "electronic designs" so the SQ would also be inconsistent.
Historically, the Marantz brand was true to it reputation - they used sophisticated "music-grade electionics". They even resorted to "borrowing" a HarmanKardon design in order to deliver the good SQ at a good price in one model.
The internal electronics of their recent models (circa 2007-present) show a southwards trend - they are now using "utilitarian' circuits instead of the more sophisticated ones. Their equivalent to the AVR4520 uses the same utilitarian design adding only their much-touted HDAM buffers while also claiming better capacitors. The HDAM serves a positive purpose but I doubt that it would improve the sound from the utilitarian base design enough to justify the expense.
Always cheaper elctronics than Marantz regardless of model.
Always decent electronics from low-end to high-end. If fact what I found from my research is that they used the same GOOD audio-grade design in most of their products. They simply put in different parts for different power handling capabilities and for pricier models HK usually adds an extra circuit in the output stage to better handle difficult speakers.
Cons: No Audyssey, aesthetics are not mainstream.