What makes a Sunsui AU 919/old stuff worth having ?

[highfigh]

I believe for older people who have had invested in such kind of gear in the past, may want to acquire some of them back for, as others mentioned, nostalgia reason. I used to own some of those heavy vintage stuff such as integrated amps but have only kept a pair of vintage Marantz amps and a CD player.

For "sound quality", people are going to claim all kinds of things but with the advance in technology it you put them through a bunch of bench tests you will find nothing or little to show why such vintage gear could/would "sound better". The AU-919's specs are in line with the Denon AVRs measured on ASR, but not better but I am sure just by looking at them and feeling the weight, the AU-919 will sound much better. The fact that the AU-919, presumably made >40 years ago, have audio specs comparable to today's amps, is truly amazing. The digital version such as the AU-X911DG, that is more than 10 years newer and expectedly lighter, have even better specs.

I have been comparing my 43 years old Marantz pair with my newest amp (a little light weight Purifi amp) and I honest can't say which one sounds better except the Purifi amp is definitely quieter only only noticeable if I am within a few mm to the drivers and max out the volume with no signal. So no, "old is better" is not a given in my opinion/experience.

S/N ratio is definitely one area where newer equipment can blow old gear out of the water- in the late-'70s, an amplifier with 85dB S/N was very good and really, noise was inaudible at that point especially if you consider the prevailing lifestyle, rooms, etc. The majority of manufacturers didn't bother with 4 Ohm performance because speakers that were in that range weren't common although some of the ones who wanted to be known for making better equipment did. A few years later, 90+ db S/N ratios were becoming 'necessary' because digital formats were breaking into the market and they needed to keep up. Frequency response wasn't a problem- a lot of decent gear was able to hit 100KHz and higher without much deviation from flat but then, they started to use cheaper power supplies and trowel out worse specs and some of the stuff available now isn't able to do much as far as 'grunt work' impedance.

Since I gave up caring if something was better or worse a long time ago, it freed me to compare equipment on its own merits, not on some opinion from hearing or reading something about it. I still have the speakers I used starting in 1979, so if I listen to equipment with them, I can decide if I like it without the variable of different speakers- if it sounds good with them, it should sound good with other speakers. It's not that they're exceptional speakers, but it's a bit like recording studios using Yamaha NS-10 speakers- they're not the best, but they're everywhere and recording/mixing engineers don't need to become accustomed to different speakers or take theirs with them when they work in different places.

 

[rjharle]

Not if I can't find someone who can repair it. Fortunately, I do know people who can repair most AV equipment but that doesn't mean I want to deal with component failures in equipment that would cause a long wait until the parts can be found or arrive from a vendor. Some models just can't be repaired because the parts can't be found or they're too expensive.

I don't think anyone's memory is so good that they can accurately compare the sound if a long period of time has passed because our mind has a great amount of influence on our memory. If bad things were happening when we heard something, I doubt the memory of anything surrounding that time will be good. I don't think I have heard anyone say "My life sucked but music sounded great!".

I sold an old Sony integrated amp (mid-'70s vintage) a few years ago and after cleaning the controls & switches, I fired it up so I could make sure everything worked as it should. While I did this work, I listened to some music through my old Fischer receiver- when I connected the Sony and listened, I suddenly remembered how great it sounded, but that was because the Fischer just doesn't sound as good. Without a comparison, I don't have a problem with it but I don't listen for sound quality when it's in use. However, that integrated amp really did sound good and if someone were to use the specs to decide anything, they're better than most of the equipment available now and with inflation, the retail price would be in the $3000 range.

If it works, it should sound very good- Sansui was one of the first companies to make slew rate a priority, although their use of direct-coupled circuits was also one of their worst enemies because if a component failed, it was like a wildfire, inside- the damage was extensive. You can look online for info about the Kenwood & Hafler pieces- I'm not sure I would recommend looking on Audio Karma- they think Sanyo receivers and anything from the early-70s through 1983 was the golden era but they do have some people who know about certain brands/models/technology, so that makes them useful. Their valuations are ridiculous, though.

If I were to do anything with those, it would have to do with checking the largest electrolytic caps, to prevent them failing. However, there's no guarantee that these failing would cause a catastrophic failure if the protection circuitry was designed properly. That Sony integrated had a couple of component failures that didn't cause any further damage.

I can get a complete cap kit for the AU 919 ($250.00) and install them myself.

As far as specs go, many folks say they can read a bunch of specs and tell you what the equipment will sound like, I don't think they take the intangibles into account. All the specs will not tell you what it will sound like; you have to hear it.

 

[PENG]

I can get a complete cap kit for the AU 919 ($250.00) and install them myself.

As far as specs go, many folks say they can read a bunch of specs and tell you what the equipment will sound like, I don't think they take the intangibles into account. All the specs will not tell you what it will sound like; you have to hear it.

Agreed to a point.. The thing is, even some designers/engineers might not have relied on listening tests to design and build their amps.

The legendary Peter Walker of Quad designed/built some of those Quad amps without using subjective listening tests to assess his designs. Don't be surprised if Sansui might have done that too..

 

[highfigh]

I can get a complete cap kit for the AU 919 ($250.00) and install them myself.

As far as specs go, many folks say they can read a bunch of specs and tell you what the equipment will sound like, I don't think they take the intangibles into account. All the specs will not tell you what it will sound like; you have to hear it.

I would look at the schematic and only change the ones that test as 'bad' or badly out of range. A device called an ESR meter will check the caps- it's possible to buy caps from companies who sell them for a lot less than someone who makes money from pre-packaged 'kits'.

The advice to recap everything is a fad. If it ain't busted, don't mess with it.

You need to discharge the electrolytic caps before touching them- 100VDC doesn't feel good when it hits and if someone has a pacemaker or other cardiac issues, it can be lethal. If it was a tube amp, the power supply caps could be storing 400+VDC and that is a much higher risk.

Do those people use dousing rods or Y-shaped yew branches to find water, too?

 

[highfigh]

Agreed to a point.. The thing is, even some designers/engineers might not have relied on listening tests to design and build their amps.

The legendary Peter Walker of Quad designed/built some of those Quad amps without using subjective listening tests to assess his designs. Don't be surprised if Sansui might have done that too..

Even back at the beginning, amplifiers and other devices were designed by taking circuits from books- the tube manufacturers had determined the typical performance of their components and needed to find out how they could be used, so they did the development. Books like the old RCA Receiving Tube Manual had graphs and circuits that applied to different amplifier classes, etc. If someone needed a power supply or input circuit, they had choices- same for tone control, phase inverter and output sections. The books had info about how to connect the different sections and once it was assembled (often on what was called 'breadboard'), it was tested. If changes were needed, they were made and if not, they made prototypes and made sure they would be somewhat reliable and durable. A lot of equipment has a mystique that's really unfounded and this is easy to see in guitar amplifiers. One camp may absolutely love one brand of amplifier (like Marshall) and say the Sun rises and sets because of them but the original model was a direct copy of a Fender Bassman with the only changes caused by the lack of availability of some components. The face panel layout is identical and the circuit, by necessity, is laid out almost identically. The Marshall JTM-45 was reverse-engineered, the Fender was built from pre-existing circuits and is called 'the grandfather of modern guitar amplifiers' because so many subsequent models were based on it.

 

[rjharle]

I would look at the schematic and only change the ones that test as 'bad' or badly out of range. A device called an ESR meter will check the caps- it's possible to buy caps from companies who sell them for a lot less than someone who makes money from pre-packaged 'kits'.

The advice to recap everything is a fad. If it ain't busted, don't mess with it.

You need to discharge the electrolytic caps before touching them- 100VDC doesn't feel good when it hits and if someone has a pacemaker or other cardiac issues, it can be lethal. If it was a tube amp, the power supply caps could be storing 400+VDC and that is a much higher risk.

Do those people use dousing rods or Y-shaped yew branches to find water, too?

Yeah, tubes are no joke. Thanks for the advice, but I know my way around a circuit board.
I know I can get all the standard caps off the shelf. It's the black cap that my give me trouble.

 

[rjharle]

Agreed to a point.. The thing is, even some designers/engineers might not have relied on listening tests to design and build their amps.

The legendary Peter Walker of Quad designed/built some of those Quad amps without using subjective listening tests to assess his designs. Don't be surprised if Sansui might have done that too..

Oh, no "Quad" the EV-4/Stereo-4 and Dynaquad, EV-4/Stereo-4, Carver Sonic Hologram Generator C-9, to the ADS Model 10 Acoustic Dimensional Synthesizer. I fell for them all. Was cool in their day

 

[PENG]

Oh, no "Quad" the EV-4/Stereo-4 and Dynaquad, EV-4/Stereo-4, Carver Sonic Hologram Generator C-9, to the ADS Model 10 Acoustic Dimensional Synthesizer. I fell for them all. Was cool in their day

It was the Quad 303 and 405 that was used as example, those are really vintage amps may be too old for even @TLS Guy to collect lol.., they are of the current dumping design too.

https://geocities.restorativland.org/ResearchTriangle/Lab/6722/pwint1.txt

TAA: How do you rate the merits of listening tests to instrument tests?

PW: We designed our valve (tube) amplifier, manufactured it, and put it on the
market, and never actually listened to it. In fact, the same applies to the 303 and
the 405. People say, "Well that's disgusting, you ought to have listened to it."
However, we do a certain amount of listening tests, but they are for specific
things. We listen to the differential distortion - does a certain thing matter?
You've got to have a listening test to sort out whether it matters. You've got to do
tests to sort out whether rumble is likely to overload pickup inputs, or whether
very high frequency stuff coming out of the pickup due to record scratch is going
to disturb the control unit. But we aren't sitting down listening to Beethoven's
Fifth and saying, "That amplifier sounds better, let's change a resistor or two. Oh
yes, that's now better still." We never sit down and listen to a music record
through an amplifier in the design stage. We listen to funny noises, funny
distortions, and see whether these things are going to matter, to get a subjective
assessment. But we don't actually listen to program material at all.

 

[PENG]

Yeah, tubes are no joke. Thanks for the advice, but I know my way around a circuit board.
I know I can get all the standard caps off the shelf. It's the black cap that my give me trouble.

If you are handy to recap and restore yourself, keep an eye on this one too:

SANSUI AU-X1 (audio-database.com)

600 VA transformer for a 160X2 W rated amp, that's a very robust power supply.

 

[TLS Guy]

Agreed to a point.. The thing is, even some designers/engineers might not have relied on listening tests to design and build their amps.

The legendary Peter Walker of Quad designed/built some of those Quad amps without using subjective listening tests to assess his designs. Don't be surprised if Sansui might have done that too..

That is because he was smart enough to know from the bench test when he had a good amp, and that the sound will be determined by the speaker unless you have a complete dog of an amp. What he was really obsessed with, was reliability, and that shows today, with the greater proportion of the output from Huntingdon still in use.

 

[TLS Guy]

It was the Quad 303 and 405 that was used as example, those are really vintage amps may be too old for even @TLS Guy to collect lol.., they are of the current dumping design too.

https://geocities.restorativland.org/ResearchTriangle/Lab/6722/pwint1.txt

TAA: How do you rate the merits of listening tests to instrument tests?

PW: We designed our valve (tube) amplifier, manufactured it, and put it on the
market, and never actually listened to it. In fact, the same applies to the 303 and
the 405. People say, "Well that's disgusting, you ought to have listened to it."
However, we do a certain amount of listening tests, but they are for specific
things. We listen to the differential distortion - does a certain thing matter?
You've got to have a listening test to sort out whether it matters. You've got to do
tests to sort out whether rumble is likely to overload pickup inputs, or whether
very high frequency stuff coming out of the pickup due to record scratch is going
to disturb the control unit. But we aren't sitting down listening to Beethoven's
Fifth and saying, "That amplifier sounds better, let's change a resistor or two. Oh
yes, that's now better still." We never sit down and listen to a music record
through an amplifier in the design stage. We listen to funny noises, funny
distortions, and see whether these things are going to matter, to get a subjective
assessment. But we don't actually listen to program material at all.

No, I have two 303s that I have had since new. They are not currently in use. I have three 405-2s in regular daily use and ten 909s in daily use. I don't even know how many of the 405 amps I have. I have at least four 405-2 not in use. The 303 is not a current dumping amp, but class A/B with triple transistor output stage, not direct coupled to the load. The first current dumper was the 405. The Quad 303 was the first really reliable solid state amp, others all blew up on a regular basis. Peter wold not issue a solid state amp, until he had solved the reliability issue. The 303 is probably the most stable and reliable amp ever. That truly earns the classic design moniker.

 

[TLS Guy]

I can get a complete cap kit for the AU 919 ($250.00) and install them myself.

As far as specs go, many folks say they can read a bunch of specs and tell you what the equipment will sound like, I don't think they take the intangibles into account. All the specs will not tell you what it will sound like; you have to hear it.

That plan is a good way to destroy your amp. Mindlessly replacing caps, is not sane vintage restoration, but lunacy. When a cap gives trouble you will know it. Then find it and replace all those caps in your Sansui, you will end up with damaged circuit boards more likely than not.

One last word of advice, stop sniffing audiophools bad breath.

 

[rjharle]

It was the Quad 303 and 405 that was used as example, those are really vintage amps may be too old for even @TLS Guy to collect lol.., they are of the current dumping design too.

https://geocities.restorativland.org/ResearchTriangle/Lab/6722/pwint1.txt

TAA: How do you rate the merits of listening tests to instrument tests?

PW: We designed our valve (tube) amplifier, manufactured it, and put it on the
market, and never actually listened to it. In fact, the same applies to the 303 and
the 405. People say, "Well that's disgusting, you ought to have listened to it."
However, we do a certain amount of listening tests, but they are for specific
things. We listen to the differential distortion - does a certain thing matter?
You've got to have a listening test to sort out whether it matters. You've got to do
tests to sort out whether rumble is likely to overload pickup inputs, or whether
very high frequency stuff coming out of the pickup due to record scratch is going
to disturb the control unit. But we aren't sitting down listening to Beethoven's
Fifth and saying, "That amplifier sounds better, let's change a resistor or two. Oh
yes, that's now better still." We never sit down and listen to a music record
through an amplifier in the design stage. We listen to funny noises, funny
distortions, and see whether these things are going to matter, to get a subjective
assessment. But we don't actually listen to program material at all.

I was just kidding

 

[rjharle]

That plan is a good way to destroy your amp. Mindlessly replacing caps, is not sane vintage restoration, but lunacy. When a cap gives trouble you will know it. Then find it and replace all those caps in your Sansui, you will end up with damaged circuit boards more likely than not.

One last word of advice, stop sniffing audiophools bad breath.

I would like to think of myself as an independent thinker having my own opinions and not prone to drinking the Cool Aid. When I posted the Sansui cap kit I was only showing what was out there; not that I thought it was a good idea and I have it on order.

I did post this to highfigh:

"Yeah, tubes are no joke. Thanks for the advice, but I know my way around a circuit board.
I know I can get all the standard caps off the shelf. It's the black cap that my give me trouble."

I never implied or posted anything about wanting to restore or rebuild anything. My original post was:

"I have squirreled away vintage like the Kenwood KA-6000, Hafler D500, and a Sansui AU-919. There appears to be a market for this vintage stuff. Now I'm not looking to sell them, I just would like to know why they are sort after. Are they superior to today's amps; if so, how? Or is it just another bunch of folks claiming "old is better". "

However, should I plan any electronic work on audio equipment, I will seek you out for your valuable advice and guidance.

The forum has posted a lot of good stuff in response to my post, and I thank you all. Great Discussion

 

[highfigh]

Yeah, tubes are no joke. Thanks for the advice, but I know my way around a circuit board.
I know I can get all the standard caps off the shelf. It's the black cap that my give me trouble.

What is the value, tolerance and working voltage? It doesn't need to be exactly the same values.

 

[highfigh]

Oh, no "Quad" the EV-4/Stereo-4 and Dynaquad, EV-4/Stereo-4, Carver Sonic Hologram Generator C-9, to the ADS Model 10 Acoustic Dimensional Synthesizer. I fell for them all. Was cool in their day

Quad the brand, not Quadraphonic.

 

[rjharle]

Quad the brand, not Quadraphonic.

I know I was just kidding.

 

[rjharle]

What is the value, tolerance and working voltage? It doesn't need to be exactly the same values.

I'm not doing any restorations. I'll contact you should that ever change. Thank You