Kreshna Aryaguna Nurzaman wrote:

Indeed, and the noise increases with more complex DSP processing.

Unfortunately unsurprising - this isn't common to all processors that can do DSP, but it isn't uncommon either; if that makes sense. 😊

D'oh! I forgot that the laptop's Windows volume control is set to barely above minimum! So yes, I wouldn't need to set the receiver's volume control above 0 db for everyday use. Still, the fact that such hissing noise exists kinda bother me.

If you never hear it, it's no problem. All amplifiers have noise of some sort/at some level.

I hope so, but is there possibility - even slight one - that certain components have gone bad and need replacement? Nonetheless, the pure direct mode produces zero hissing noise - which shows that Yamaha receiver also works as excellent stereo amplifier.

Perhaps, but it's unlikely - sounds like everything is working properly. Especially if pure direct and other modes work properly and it isn't clicking off or going into protection or whatever while operating.

PS: it kinda surprises me that a game as old as 1987 actually support Dolby Surround. Can't wait to test it on the Yammie - if I had an Amiga, that is. 😉

Dolby Surround is older than that, at least in one iteration or another. Shame that more modern things don't take advantage of its versatility though. 😊

obobskivich wrote:

Kreshna Aryaguna Nurzaman wrote:

Indeed, and the noise increases with more complex DSP processing.

Unfortunately unsurprising - this isn't common to all processors that can do DSP, but it isn't uncommon either; if that makes sense. 😊

Guess I got the point. 😁

obobskivich wrote:

D'oh! I forgot that the laptop's Windows volume control is set to barely above minimum! So yes, I wouldn't need to set the receiver's volume control above 0 db for everyday use. Still, the fact that such hissing noise exists kinda bother me.

If you never hear it, it's no problem. All amplifiers have noise of some sort/at some level.

Nah, not my 'Sui. 😎

Okay, got your point. What I mean is the AU-7900's noise is never audible - even at max volume level. The Yammie's Pure Direct mode doesn't have audible noise either.

obobskivich wrote:

I hope so, but is there possibility - even slight one - that certain components have gone bad and need replacement? Nonetheless, the pure direct mode produces zero hissing noise - which shows that Yamaha receiver also works as excellent stereo amplifier.

Perhaps, but it's unlikely - sounds like everything is working properly. Especially if pure direct and other modes work properly and it isn't clicking off or going into protection or whatever while operating.

Ah I see, thanks! Now I just have to test its pre outs. If they work fine, then I can leave the seller a positive feedback, though his packaging is damn sloppy! 🤣

It kinda surprises me that the receiver still works correctly, considering the impact it suffered during shipping - to the point that its front-left plastic feet has broken. 🙁 Nonetheless, the receiver is built like tank, and it's only a mid-end receiver. Not as low end as Yamaha HT-in-a-box, but certainly doesn't belong in the same class with the RX-V1900.

obobskivich wrote:

PS: it kinda surprises me that a game as old as 1987 actually support Dolby Surround. Can't wait to test it on the Yammie - if I had an Amiga, that is. 😉

Dolby Surround is older than that, at least in one iteration or another. Shame that more modern things don't take advantage of its versatility though. 😊

Indeed, though in terms of computer games, 1987 was probably considered 'early years'. But then again, it's Amiga - which was ahead of IBM PC in terms of graphics and sound.

What is the earliest IBM PC game that supports Dolby Surround? According to Mobygames, it's The 7th Guest, but I wonder if MG there is another game that predates it.

Kreshna Aryaguna Nurzaman wrote:

It kinda surprises me that the receiver still works correctly, considering the impact it suffered during shipping - to the point that its front-left plastic feet has broken. 🙁 Nonetheless, the receiver is built like tank, and it's only a mid-end receiver. Not as low end as Yamaha HT-in-a-box, but certainly doesn't belong in the same class with the RX-V1900.

In my experience, the stuff that usually gets smushed in shipping is either very well packaged or has zero packaging - the stuff that's "sloppily packaged" for whatever reason always seems to survive. For example I've ordered parts that have come in multiple layers of foam, bubble wrap, etc inside of heavy corrugated boxes and still arrived smashed, but I've also ordered parts that come wrapped in construction paper and anti-static (and went through INTERNATIONAL shipping like that) and are fine. Go figure. 🙄

What is the earliest IBM PC game that supports Dolby Surround? According to Mobygames, it's The 7th Guest, but I wonder if MG there is another game that predates it.

Honestly no clue. I think finding the answer may also be complicated by geographic region for release, and if you are confining to IBM or just "any game" (there are console games that can use it (there are actually console games that use Pro Logic II even)). The unfortunate thing, imho, is that even though there were games in 1980s using this - it didn't become universally adopted by games over the next 10 years, like it did with home video. 😢

obobskivich wrote:

In my experience, the stuff that usually gets smushed in shipping is either very well packaged or has zero packaging - the stuff that's "sloppily packaged" for whatever reason always seems to survive. For example I've ordered parts that have come in multiple layers of foam, bubble wrap, etc inside of heavy corrugated boxes and still arrived smashed, but I've also ordered parts that come wrapped in construction paper and anti-static (and went through INTERNATIONAL shipping like that) and are fine. Go figure. 🙄

Does it mean... the better the item being packed, the more likely the airport guys to play dodgeball with it? 🤣

obobskivich wrote:

Honestly no clue. I think finding the answer may also be complicated by geographic region for release, and if you are confining to IBM or just "any game" (there are console games that can use it (there are actually console games that use Pro Logic II even)). The unfortunate thing, imho, is that even though there were games in 1980s using this - it didn't become universally adopted by games over the next 10 years, like it did with home video. 😢

Indeed, console games are designed with TV in mind, so it's natural they adopted things like Dolby Surround earlier. Still, there are only few early games adopted DS either, console or otherwise. 😢

Now I'm gonna try wacky things with the receiver, like connecting my old Atari Jr to the receiver (need RF to RCA converter though) and hear the "bleep bloop" sound in CinemaDSP, with presence speakers! 🤣 Seriously, when I was little, my parents took us (me and my brother) to an exhibition. They allowed the visitors to play Atari games with big screen CRT TV, using large bookshelf speakers. I was playing Asteroids at that time. I was too small to remember exactly, but the game sound - despite nothing more than bleep bloop - sounded spacious and awesome.

Kreshna Aryaguna Nurzaman wrote:

Does it mean... the better the item being packed, the more likely the airport guys to play dodgeball with it? 🤣

I've often wondered... 🤣

Indeed, console games are designed with TV in mind, so it's natural they adopted things like Dolby Surround earlier. Still, there are only few early games adopted DS either, console or otherwise. 😢

Now I'm gonna try wacky things with the receiver, like connecting my old Atari Jr to the receiver (need RF to RCA converter though) and hear the "bleep bloop" sound in CinemaDSP, with presence speakers! 🤣 Seriously, when I was little, my parents took us (me and my brother) to an exhibition. They allowed the visitors to play Atari games with big screen CRT TV, using large bookshelf speakers. I was playing Asteroids at that time. I was too small to remember exactly, but the game sound - despite nothing more than bleep bloop - sounded spacious and awesome.

Overkill: to the max! 🤣 😎

obobskivich wrote:

Kreshna Aryaguna Nurzaman wrote:

Does it mean... the better the item being packed, the more likely the airport guys to play dodgeball with it? 🤣

I've often wondered... 🤣

Seriously? They do? :shock:

obobskivich wrote:

Indeed, console games are designed with TV in mind, so it's natural they adopted things like Dolby Surround earlier. Still, there are only few early games adopted DS either, console or otherwise. 😢

Now I'm gonna try wacky things with the receiver, like connecting my old Atari Jr to the receiver (need RF to RCA converter though) and hear the "bleep bloop" sound in CinemaDSP, with presence speakers! 🤣 Seriously, when I was little, my parents took us (me and my brother) to an exhibition. They allowed the visitors to play Atari games with big screen CRT TV, using large bookshelf speakers. I was playing Asteroids at that time. I was too small to remember exactly, but the game sound - despite nothing more than bleep bloop - sounded spacious and awesome.

Overkill: to the max! 🤣 😎

🤣 Already tried it with my lower-end Yamaha (the one in the living room), sounded quite "bassy" with the Whardefales, but no presence speakers.

Yamaha RX-V663 HT receiver - A Short Review
by Kreshna Aryaguna Nurzaman

...and they said all amplifier sounds the same, so why the hell do I still hear differences between them? 😕

So, I have finished testing the Yamaha RX-V663's functionality with two pair of old speakers (Kenwood and Hitachi), and everything works well. I gave the seller a positive feedback he deserves, and now it's time to hook the HT receiver to my JBL 120Tis. Still in stereo, though, since the wall plates and cable ducting for the rear speakers (JBL L20Ts) are not yet installed. But of course, the reviews said the RX-V663 has good 'musical quality' despite being an AV receiver, so I am very tempted to test it for stereo listening. I use pure direct mode to eliminate DSP-related variables, and here's what I got.

Note(s):
(1) my Sansui AU-7900 is dead now, but I still remember its sound thoroughly. I really enjoyed listening to the AU-7900, that I think I sub-consciously did critical listening all the time, and memorized its sound and use it as reference to measure other amplifiers.
(2) my Sansui A40 is already in beaten condition when I bought it in April, so I guess it actually sounds better than what I describe here.

Tonality.

The Yamaha RX-V663 sounds clearer and more detailed than my beaten Sansui A-40. HF sounds like cymbals and hi-hats are better defined, and so is sibilance (and I like sibilance). And the bass sounds better too! The bass is still weaker than that of NAD C375BEE, but the whole tonality is still flatter and more neutral than the NAD.

However, the Sansui AU-7900 still beats the Yamaha RX-V663 in HF cleanliness. The AU-7900's cymbals and hi-hats are as loud as those of the RX-V663, but cleaner, more real, and more convincing.

Much to my surprise, the AU-7900 has weaker midbass than the so-called 'bright' Yamaha. Nope, the RX-V663 pure direct mode is actually less bright than the AU-7900. Only when I use the Yamaha's 2 channel mode, then the brightness actually approaches that of the Sansui.

In terms of brightness, it goes like this (from bright to meaty):
Sansui AU 7900 => Yamaha RX-V663 => Sansui A40 => Kenwood DC 20P

So, huh? Is Sansui really a "warm and tubey" amplifier? Because not only the AU-7900 actually has weaker midbass than the RX-V663, but the entire sound is also brighter and cleaner. 😕 😕

Stereo imaging and sound stage.

This is actually the weakest point of the RX-V663. You see, even the beaten up Sansui A40 has better, more pinpointed stereo imaging than the RX-V663's pure direct mode. And my Sansui A40 is already so beaten that it drops its right channel sometimes, that I have to repeatedly beat it on its right side to restore the missing channel. 🤣 And yet, its stereo imaging is still better than that of the RX-V663.

Well the Yamaha isn't all bad: stereo imaging does exist, but its more "wall of sound" than pinpointed imaging. I mean, even the beaten up Sansui A40 has better stereo imaging than that, so huh?

To be fair, the Yamaha's stereo imaging gets better.... once you activate its DSP (virtual CinemaDSP because I only use two speakers). I played Command & Conquer: Tiberian Sun using the Yamaha's Strategy Game mode, and the stereo imaging became better defined, more pinpointed. But using DSP defeats the purpose of hi-fidelity, does it?

As for sound stage, my beaten Sansui A40 also is still better than the Yamaha RX-V663 receiver. Take a listen on this Pet Shop Boys song. The song starts with a sequence of (synthesized) snare drums. Even with my Sansui A40, the snare drums comes from far away behind the left speaker. Alas, that's not the case with the Yamaha.

The Sansui AU-7900, on the other hand, beats the Yamaha hands down in sound stage department. I still remember listening to the song The Lonely Goatherd from the The Sound of Music soundtrack; there was a a moment where I instinctively turned my head to check the wall behind my right shoulder, because there was a sound that appeared to come from that spot despite I'm listening in stereo! 🤣

Dynamics.

Again, this is another weak point of the Yamaha RX-V663 receiver. I tested it using Mozart's Eine Kleine Nachtmusik, and the whole music seems dynamically compressed. Even with the Sansui A40, the quiet sounds quiet, and the loud sounds loud. That's not the case with the Yamaha RX-V663, where the quiet parts of the music are not quiet enough, and vice versa.

That's really mind boggling, because the Yamaha RX-663 is supposed to be a home theater receiver; it should be able to handle the dynamics of movies - which is supposed to be greater than music. But then again, activating its DSP makes the dynamics better. Again, I tested it with Tiberian Sun on CinemaDSP's Strategy Game mode, and the quiet becomes quieter, while the loud becomes louder.

Power.

I have a Harry Belafonte album titled Harry Belafonte Sings The Blues. I don't know whether the album is poorly mastered, because with low-powered amplifiers like Kenwood DC-20P and Sansui A40, Harry Belafonte's vocals always clip in high volume. That's never the case with either the Sansui AU-7900 and the Yamaha RX-V663. Both amplifiers drive my JBL 120Ti effortlessly and authoritatively, and Belafonte's vocals are loud and clear. Power-wise, it seems the AU-7900 and the RX-V663 are on par with each other, although it should be noted that the former is only rated 75 wrms per channel while the latter 95 wrms per channel.

Miscellaneous.

Once thing I really like from the Yamaha RX-V663 is there's no popping sound at all from my speakers when I turn off the unit. Even the Sansui AU-7900 still makes the speaker pop when I turn it off - except if turn off the speaker channel beforehand. The Sansui A40 is the worst in this matter; even turning off the speaker channel makes the speaker pop.

What I cannot tolerate from the RX-V663 is the hissing sound in loud volume; even the A40 doesn't hiss, and it's not really in a good shape.

Conclusion.

I have to say that Yamaha RX-V663 HT receiver is also a competent stereo amplifier; it has neutral and flat sound, and it has plenty of power to handle the JBL 120Tis' heavy aquaplas woofers. However, its stereo imaging and dynamics (or the lack thereof - at least compared to Sansui) makes it a rather unexciting amplifier. My Sansui AU-7900 is more exciting and musical - while still being clinical. To be frank, the RX-V663's imaging and dynamics improve when you use its DSP, but it defeats the purpose of 'high-fidelity'.

As for Yamaha amplifiers being bright, I fail to notice any brightness at all in pure direct mode. But then again, it becomes bright when you use its DSP.

Further questions and discussions.

(1) Which amplifier part has bigger impact on sound quality? Pre or power? If the Yamaha gets better stereo imaging and dynamics with its DSP turned on, does it mean that its preamp part (the DSP, that is) has greater impact on sound quality? Yes, DSP is not hi-fi, but it 'improves' (enhances) sound quality nonetheless.

(2) What makes both Sansui A40 and AU-7900 better than the Yamaha RX-V663 pure direct mode in stereo imaging and dynamics? Is that the preamp part, or the power amp part? Unlike AU-7900, A40 doesn't have separate preamp/power amp mode, but I think the pre and power are still discrete with each other.

(3) If preamp has bigger impact on sound quality than power amp (in other words, any power amp with sufficient power is enough as long as it doesn't suck), then why many people use their integrated amplifier's HT bypass mode to enhance their HT receiver's sound in stereo mode? Because in HT bypass mode, the integrated amplifier strictly works as power amp only, while the 'preamp sound' comes from the HT receiver.

(3) For stereo music, if I connect my AU-7900 preamp into the Yamaha RX-V663 stereo input while using pure direct mode (once the AU-7900 recapped), would the stereo imaging and the dynamics get better? Yes, there is still problem with stacking volume controls, but thanks to large display and stiff volume control knob, I can easily set and keep the RX-V663's master volume in 0 dB (unity gain), then use the AU-7900 as master volume control.

That's also my plan with games, by the way. It seems I need a Sound Blaster X-Fi USB anyway to get EAX and A3D. Alas, the X-Fi also has its own volume control, so I plan to keep the RX-V663's volume control in 0 db, then use the X-Fi volume control as master volume control.

(4)Still related to #3, the RX-V663 manual says that in pure direct mode, the volume control is the only thing that affects the sound. So, is the RX-V663 pure direct mode equals to power amp with attenuator, at least up to 0 db? Same goes with its multichannel analog input, where no DSP processing possible when using multichannel input.

For better or worse, sounds like "typical Yamaha receiver" right there. 😀

The popping on the speakers is prevented by switching relays - most modern devices will feature this, but generally older components do not have this feature.

On your questions:

1) I think it's tough to say - whichever is "worse" in a given system is probably a better answer. IOW if you have a really killer pre-amp and a dumpy power amp, the power amp is going to be a bigger impact, if you have a killer power amp and dumpy pre-amp it's then on the pre-amp. In a perfect world where both components are nice, it's still tough to say because some components are designed to be fairly neutral/get out of the way, while others are designed to be colored or otherwise impart their own "flavor" onto what they're doing. IME pre-amps are usually where problems appear in separates systems (channel imbalance, pot noise, input sensitivity mismatch, etc) where power amps are usually where the problems appear in integrated systems (where they're usually victims of scale).

2) It's probably the power amp.

3) Because it's cool? 🤣 I don't really have any answers there beyond that - I've always thought it was neato to have a separate stereo system that your surround sound just "piggybacked" on when you want surround. It's also probably more power efficient with modern AVRs (some of those things that can use 100W+ just in standby because of all the networking/processing junk they have).

3) (4) I doubt it - the Yamaha doesn't have a way to fully bypass its preamp or DSP processor, even in Pure Direct mode. It's just turning a lot of internal features off, but not pulling them entirely out of the chain. It isn't like the Sansui where you can just unhook the preamp at the inserts, and go straight into its power amp. You'd also probably have to contend with the noise coming thru the Yamaha with it set to 0 dB or higher to use it as a "line receiver" from the Sansui.

5) Yes and no. It isn't using a separate path for volume control - it's using whatever (likely DSP based) method it uses the rest of the time. It's just disabling various functionality in the DSP when that's enabled - the idea is to have an "unprocessed signal" not a "straighter path" - but they aren't extremely candid about that. The multi-ch analog input isn't being digitized - it's just going straight into the attenuation/pre-amp sections; they don't digitize these because it requires extra circuitry (there are some (exorbitantly expensive) pre-amps that will digitize and process their multi-ch inputs, but in general it's just not something receivers/preamps do)).

Hold on, this is the most interesting part, so I'm putting it first:

obobskivich wrote:

5) Yes and no. It isn't using a separate path for volume control - it's using whatever (likely DSP based) method it uses the rest of the time. It's just disabling various functionality in the DSP when that's enabled - the idea is to have an "unprocessed signal" not a "straighter path" - but they aren't extremely candid about that. The multi-ch analog input isn't being digitized - it's just going straight into the attenuation/pre-amp sections; they don't digitize these because it requires extra circuitry (there are some (exorbitantly expensive) pre-amps that will digitize and process their multi-ch inputs, but in general it's just not something receivers/preamps do)).

So, the RX-V663's multi-channel analog input is the least touched, isn't it?

Alright, let's assume that the receiver's multi-channel analog is nothing more than power amp with attenuator at 0 dB (unity gain), or probably preamp with attenuator with preamp coloration being negligible. So what's wrong with the following configuration?

1[external DAC]
2      |
3      |
4   stereo
5      |
6      |
7      v
8[Sansui AU 7900] *
9 (preamp part)
10      |
11      |
12   stereo
13      |
14      |
15      v
16[Surround Master] *
17   |       |
18   |       |
19 front    rear
20   |       |
21   |       |
22   v       v
23[Yamaha RX-V663]
24(using multi-ch
25 analog inputs)
26   |       |
27   |       |
28 front    rear
29   |       |
30   |       |
31   v       v
32[front] [rear] 
33[spk  ] [spk ]
34
35(*) indicates volume control

The configuration above is for music listening with Involve Audio Surround Master to generate surround music. In the configuration above, I use the Sansui AU-7900's preamp section to "color" the entire sound with the "Sansui sound". The Sansui's preamp output goes into the Surround Master, processed into 4.0, then sent to the Yamaha RX-V663 multi-channel analog inputs - which is supposed to be the least processed by the receiver.

Assuming that the Yamaha's preamp coloration is negligible, then the only downside of the configuration above is serially stacking volume controls. That is, the Sansui AU-7900's volume control and the Yamaha RX-V663's volume control. And stacking volume controls is bad because it increases distortion and may cause clipping. Well at least that's what you told me in one of our PMs. 😊

But it is very easy to keep the Yamaha's volume control at 0 dB (unity gain), because the volume control knob is very stiff and precise. In fact, I think I'm going to keep it at 0 dB because I cannot stand the hiss it generates above 0 dB. As such, for games I'm going to use the Sound Blaster X-Fi's master volume control while keeping the Yamaha's at 0 dB.

1[SB X-Fi surround 5.1 USB] *
2      |
3      |
4   S/PDIF
5      |
6      |
7      v
8[Yamaha RX-V663] *
9   |       |
10   |       |
11 front    rear
12   |       |
13   |       |
14   v       v
15[front] [rear] 
16[spk  ] [spk ]
17
18(*) indicates volume control

Then it came into my mind: if I'm going to use the X-Fi's volume control while keeping the Yamaha's volume control at 0 dB, why not doing the same with Sansui?

In fact, I can have more "advanced" configuration like shown below.

1[external DAC]
2      |
3      |
4   stereo
5      |
6      |
7      v
8[Sansui AU 7900] *
9(preamp section)
10      |
11      |
12   stereo
13      |
14      |
15      v
16[Surround Master] *
17   |         |
18   |         |
19 front      rear
20   |         |
21   |         |
22   v         v
23[Yamaha RX-V663]
24(using multi-ch
25 analog inputs)
26   |         |
27   |         |
28 front      rear
29(pre-out)    |
30   |         |
31   |         |
32[Sansui]     |
33[AU-7900]    |
34(power amp   |       
35secion)      |
36   |         |
37   |         |
38   v         v
39[front]   [rear] 
40[spk  ]   [spk ]

Yep, in the configuration above I use both the Sansui's preamp and power amp section for front channel, while letting the Yamaha drive the rear channel. Again, the Yamaha volume control needs to be kept at 0 dB with such configuration, but like I said, keeping the Yamaha volume control at 0 dB is pretty easy.

So what would you think of it? 🤣

obobskivich wrote:

For better or worse, sounds like "typical Yamaha receiver" right there. 😀

I wouldn't know, my other Yamaha receiver is an el-cheapo YHT series. 🤣

Seriously, is it normal for an RX series to perform not as good as a beaten-up vintage Sansui? 🙁

obobskivich wrote:

The popping on the speakers is prevented by switching relays - most modern devices will feature this, but generally older components do not have this feature.

Indeed. Even the AU-7900 still makes the speakers pop when the amplifier is turned off - and it does have protection relays.

obobskivich wrote:

On your questions:

1) I think it's tough to say - whichever is "worse" in a given system is probably a better answer. IOW if you have a really killer pre-amp and a dumpy power amp, the power amp is going to be a bigger impact, if you have a killer power amp and dumpy pre-amp it's then on the pre-amp. In a perfect world where both components are nice, it's still tough to say because some components are designed to be fairly neutral/get out of the way, while others are designed to be colored or otherwise impart their own "flavor" onto what they're doing. IME pre-amps are usually where problems appear in separates systems (channel imbalance, pot noise, input sensitivity mismatch, etc) where power amps are usually where the problems appear in integrated systems (where they're usually victims of scale).

I see. In the case of Yamaha, then the suspect is more likely the power amp section.

Well, one thing for sure, the Yamaha RX-V663 feels lighter than the Sansui AU-7900, and the former is 7 channels while the latter is only two.

obobskivich wrote:

2) It's probably the power amp.

I see. Well it's completely understandable if the Sansui AU-7900 beats the Yamaha RX-V663 in power department. What surprises me is the A40, which is low power, and does clip with my Belafonte album. The Yamaha doesn't, yet its imaging and dynamics are worse than the A40 (though not far worse).

obobskivich wrote:

3) Because it's cool? 🤣 I don't really have any answers there beyond that - I've always thought it was neato to have a separate stereo system that your surround sound just "piggybacked" on when you want surround. It's also probably more power efficient with modern AVRs (some of those things that can use 100W+ just in standby because of all the networking/processing junk they have).

Whoa, including Yamaha? I

obobskivich wrote:

3) (4) I doubt it - the Yamaha doesn't have a way to fully bypass its preamp or DSP processor, even in Pure Direct mode. It's just turning a lot of internal features off, but not pulling them entirely out of the chain. It isn't like the Sansui where you can just unhook the preamp at the inserts, and go straight into its power amp. You'd also probably have to contend with the noise coming thru the Yamaha with it set to 0 dB or higher to use it as a "line receiver" from the Sansui.

Fortunately the noise only comes above 0 dB. At 0 dB, I fail to hear any. 😀

Kreshna Aryaguna Nurzaman wrote:

So, the RX-V663's multi-channel analog input is the least touched, isn't it?

Not explicitly - it will have the least filtering available most likely, but stereo input + pure direct is probably analogous.

Alright, let's assume that the receiver's multi-channel analog is nothing more than power amp with attenuator at 0 dB (unity gai […]
Show full quote

Alright, let's assume that the receiver's multi-channel analog is nothing more than power amp with attenuator at 0 dB (unity gain), or probably preamp with attenuator with preamp coloration being negligible. So what's wrong with the following configuration?

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1[external DAC]
2      |
3      |
4   stereo
5      |
6      |
7      v
8[Sansui AU 7900] *
9 (preamp part)
10      |
11      |
12   stereo
13      |
14      |
15      v
16[Surround Master] *
17   |       |
18   |       |
19 front    rear
20   |       |
21   |       |
22   v       v
23[Yamaha RX-V663]
24(using multi-ch
25 analog inputs)
26   |       |
27   |       |
28 front    rear
29   |       |
30   |       |
31   v       v
32[front] [rear] 
33[spk  ] [spk ]
34
35(*) indicates volume control

The configuration above is for music listening with Involve Audio Surround Master to generate surround music. In the configuration above, I use the Sansui AU-7900's preamp section to "color" the entire sound with the "Sansui sound". The Sansui's preamp output goes into the Surround Master, processed into 4.0, then sent to the Yamaha RX-V663 multi-channel analog inputs - which is supposed to be the least processed by the receiver.

Still stacking gain stages, preamps, etc. Just feed the surround master from whatever its sourcing from (DAC or whatever) into the multi-ch input. 😊

So what would you think of it? 🤣

You can't drive the power amp into the line-in, unless I'm not understanding you right.

Seriously, is it normal for an RX series to perform not as good as a beaten-up vintage Sansui? 🙁

RX series is pretty broad, so it's tough to characterize them all in one way I would think.

Indeed. Even the AU-7900 still makes the speakers pop when the amplifier is turned off - and it does have protection relays.

Maybe something is wrong with the protection circuitry? 😕

Whoa, including Yamaha? I

Yeah a lot of brand-new network/HDMI/4k/3D/etc yadda yadda do-everything including slice the bread devices use quite a lot of power even in standby or at idle. Older receivers tend not to be as bad, especially in standby, as they don't have as much "computer guts" to run all the time, so it's just the amp's power consumption when it's actually running.

obobskivich wrote:

Not explicitly - it will have the least filtering available most likely, but stereo input + pure direct is probably analogous. […]
Show full quote

Kreshna Aryaguna Nurzaman wrote:

So, the RX-V663's multi-channel analog input is the least touched, isn't it?

Not explicitly - it will have the least filtering available most likely, but stereo input + pure direct is probably analogous.

Alright, let's assume that the receiver's multi-channel analog is nothing more than power amp with attenuator at 0 dB (unity gai […]
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Alright, let's assume that the receiver's multi-channel analog is nothing more than power amp with attenuator at 0 dB (unity gain), or probably preamp with attenuator with preamp coloration being negligible. So what's wrong with the following configuration?

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1[external DAC]
2      |
3      |
4   stereo
5      |
6      |
7      v
8[Sansui AU 7900] *
9 (preamp part)
10      |
11      |
12   stereo
13      |
14      |
15      v
16[Surround Master] *
17   |       |
18   |       |
19 front    rear
20   |       |
21   |       |
22   v       v
23[Yamaha RX-V663]
24(using multi-ch
25 analog inputs)
26   |       |
27   |       |
28 front    rear
29   |       |
30   |       |
31   v       v
32[front] [rear] 
33[spk  ] [spk ]
34
35(*) indicates volume control

The configuration above is for music listening with Involve Audio Surround Master to generate surround music. In the configuration above, I use the Sansui AU-7900's preamp section to "color" the entire sound with the "Sansui sound". The Sansui's preamp output goes into the Surround Master, processed into 4.0, then sent to the Yamaha RX-V663 multi-channel analog inputs - which is supposed to be the least processed by the receiver.

Still stacking gain stages, preamps, etc. Just feed the surround master from whatever its sourcing from (DAC or whatever) into the multi-ch input. 😊

Even with the Yamaha set at 0 dB?

obobskivich wrote:

So what would you think of it? 🤣

You can't drive the power amp into the line-in, unless I'm not understanding you right.

Nope, the Yamaha's front line out goes to the Sansui's power amp in, not the Sansui's line in. The Sansui has separate mode, remember?

obobskivich wrote:

Seriously, is it normal for an RX series to perform not as good as a beaten-up vintage Sansui? 🙁

RX series is pretty broad, so it's tough to characterize them all in one way I would think.

Well at least RX-V663. I guess RX-V1400 and the likes would be better though.

obobskivich wrote:

Indeed. Even the AU-7900 still makes the speakers pop when the amplifier is turned off - and it does have protection relays.

Maybe something is wrong with the protection circuitry? 😕

It seems that's the case.

obobskivich wrote:

Whoa, including Yamaha? I

Yeah a lot of brand-new network/HDMI/4k/3D/etc yadda yadda do-everything including slice the bread devices use quite a lot of power even in standby or at idle. Older receivers tend not to be as bad, especially in standby, as they don't have as much "computer guts" to run all the time, so it's just the amp's power consumption when it's actually running.

I see. Well that's why I turn off the receiver when not using it - instead of my vintage amplifiers, which I tend to leave them on all the time. 🤣

Anyway, what would you think about partially-obscured woofers?

My current speaker heights, relative to my desk, is approximately as follows:

So you see, the woofers are partially below the desk surface. However, it doesn't cause problem in my current listening position.

What if I move my listening position here? Will it cause problem?

I can always raise my mains so that the woofers won't be obscured, but that way, the tweeters will be above my ears. So if you have to choose between two evils, which one is the lesser evil?
(1) woofers are partially obscured (part of the woofers are below desk's surface), but tweeters are at ear levels.
(2) woofers are not obscured, but tweeters are higher ear levels.

Yeah I still wouldn't stack preamps even if one as at 0 dB. As far as the power draw - even with some newer receivers "off" (e.g. you click their power buttons and they're in stand-by waiting for the remote to send an ON signal) they can still draw silly power. Unplugging them is usually the only option if you want to kill power draw...

I doubt the 663 is that new - but you may hook it up to a power meter just to test.

Woofers being blocked shouldn't be a problem - like I don't think they'd be damaged (unless you have like a board/wall right on top of them that obstructs their movement), but it may change bass a little (probably will increase it if you're basically backing them into a corner). Should be fine though - probably less bad than having the tweeters way above you.

obobskivich wrote:

Yeah I still wouldn't stack preamps even if one as at 0 dB.

Are there still clipping and distortion even at 0 dB? Or is it a different problem altogether? Like coloration.

obobskivich wrote:

As far as the power draw - even with some newer receivers "off" (e.g. you click their power buttons and they're in stand-by waiting for the remote to send an ON signal) they can still draw silly power. Unplugging them is usually the only option if you want to kill power draw...

I doubt the 663 is that new - but you may hook it up to a power meter just to test.

I see.

obobskivich wrote:

Woofers being blocked shouldn't be a problem - like I don't think they'd be damaged (unless you have like a board/wall right on top of them that obstructs their movement), but it may change bass a little (probably will increase it if you're basically backing them into a corner). Should be fine though - probably less bad than having the tweeters way above you.

I see, thanks! 😀 Wonder what would happen if I coat my desk (the side that obstruct the woofers) with sound absorbers. It may eliminate the unnecessary bass increase, but it may also really block some part of the sound. I wonder how would it sound.

Kreshna Aryaguna Nurzaman wrote:

Are there still clipping and distortion even at 0 dB? Or is it a different problem altogether? Like coloration.

Noise, primarily. If it sounds fine and you don't have noise coming through, it may work just fine then, but usually stacking (analog) preamps leads to noise/interference.

I see, thanks! 😀 Wonder what would happen if I coat my desk (the side that obstruct the woofers) with sound absorbers. It may eliminate the unnecessary bass increase, but it may also really block some part of the sound. I wonder how would it sound.

If you're thinking of like eggcrate foam, it won't do anything for you - it lacks the mass, depth, etc to deal with low frequencies. I'd say try the speakers in the position you want, and if it's a problem try moving them to somewhere that isn't a problem.

obobskivich wrote:

Kreshna Aryaguna Nurzaman wrote:

Are there still clipping and distortion even at 0 dB? Or is it a different problem altogether? Like coloration.

Noise, primarily. If it sounds fine and you don't have noise coming through, it may work just fine then, but usually stacking (analog) preamps leads to noise/interference.

I see. Worth trying, I guess. Once I have the AU-7900 completely restored, of course.

obobskivich wrote:

I see, thanks! 😀 Wonder what would happen if I coat my desk (the side that obstruct the woofers) with sound absorbers. It may eliminate the unnecessary bass increase, but it may also really block some part of the sound. I wonder how would it sound.

If you're thinking of like eggcrate foam, it won't do anything for you - it lacks the mass, depth, etc to deal with low frequencies. I'd say try the speakers in the position you want, and if it's a problem try moving them to somewhere that isn't a problem.

No, not sound dispersion panel like eggcrate foam, but sound deadening board, like the one you put behind the speakers to eliminate first-order reflection.