Sound Quality Vs. Measurements

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A question.

I have a preamp, by Philips' prestige Black Tulip series, model AH280. It was OEMed for Philips in Japan, and I would guess by Hitachi, since most of the transistors and ICs are by them.

The topology is fully complementary and discrete throughout, but it is an AC rather than a DC device, meaning it uses coupling capacitors between stages.

In my lineup, with their AH180 digitaly synthesized tuner, AH280 preamp and AH370 power amp (smaller of the two offered, rated at 60W/8 Ohms, bigger model AH380 rated at 100W/8 Ohms, totally identical inside except that the bigger model has two pairs of output devices per channel and higher rails), the preamp is the weak link.

The tuner has a very pleasing sound, even if it's not supremely neutral. The power amp is all right, nothing to write home about, but no obvious flaws. The preamp is, unfortunately, rather spitty and shouty. It tends to glare, and subjectively its mid and high ranges absolutely dominate the sound. If you make the fatal mistake of pressing the loudness switch, you are immediately made aware of the reasons why they have a bad rep, the sound goes all boomy and in general crappy.

Now, the behavior of the loudness switch can be changed by changing part values, so that doesn't worry me. But if you were me, what would you look at regarding the problems of being shouty?

General pointers welcome.
 
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do this every day of their lives ?

They most likely spend their time the same way you do and/or have done.

(last year I talked to a Cannes resident who spent most of his time looking at boats, on/off the web, in his early '70s. Each time it's busy-body in Cannes, he and his wife leave for R&R elsewhere)

House of a fellow former Delft university gent : Landhuis Ronde Klip - Van Olst Real Estate Curaçao
He started a software company with friends at age 22, cashed in at age 37 and left for the Caribbean.
The IT pirate deceased a few years ago, house is now offered for a fraction of the enormous renovation cost.
 
The preamp is, unfortunately, rather spitty and shouty. It tends to glare, and subjectively its mid and high ranges absolutely dominate the sound. If you make the fatal mistake of pressing the loudness switch, you are immediately made aware of the reasons why they have a bad rep, the sound goes all boomy and in general crappy.

Now, the behavior of the loudness switch can be changed by changing part values, so that doesn't worry me. But if you were me, what would you look at regarding the problems of being shouty?

General pointers welcome.
I would find it an interesting challenge - sounds like the usual symptoms of over-complicated devices; too many weaknesses overwhelm the ability of the component to deliver reasonable sound, and it ends up a subjective disaster.

I would start by creating a super-clean electrical environment for it to operate in, condition it by running it 24/7 for a few days; if that showed potential I would bypass every complication it had internally, turn it into the simplest electrical device I could manage - I want to know how clean the intrinsic circuit is, without all the auxiliary crap degrading things ....
 
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Not even the round off change in the Dr. Dre deal. I hear Tom bought a piece of a local college not 15min. from me to build another one, sans moat.

Its enough to make a socialist or communist of anyone. . .

Why would either Jimmy or Dr. Dre show up at Apple after that payoff? They won't get enough richer to be able to see a difference.

It also brings into question Apple and their ability to hatch new ideas. $3B hiring bonus to get some smart guys seems excessive.
 
Gotta get your countries right, Scott, you're talking about the primitives next door, in Kiwi land - after all, people who like hanging out with sheep must have a few other eccentricities ... ;).

The mob over there are trying to escape here, so that they don't get put into a mental asylum for picking at the wrong parts of their body, and we have to put up with them, :D!
 
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What to do with Billions - then what?

These 'deals' come with a lot of conditions.... you get this and that - if we get this or that. Sort of like the sports 'figures'. IF they win every game and the super-duper final play-off can they make top dollar. So, lok at the guarenteed minimum number instead... or what the stock part of the payment is currently worth. etc. A lot of conditions..... but its still a lot.

I have seen and followed the careers of a few who are mulit-millionares. I now define Richa s people who worked for it and if they stopped working, the money would soon stop as well. I define wealthy as those who are rich whether they work at it or not... like super rich = wealthy. Such as those who are born into wealth and never will have to work. Rich. wealthy. I would go nuts being wealthy (bored) if I couldnt be actively involved in doing something with the wealth.... maybe like Gates...... kept mentally involved and busy. And, I'm only retired and it is easy to get bored. W.Buffet understands this about being rich or wealthy..... there are a limited number of things to play with... bigger or more homes, cars, boats/Yachts and airplanes. larger, better A-V gear/room? Thats all there is. Oh, and shoes. Then what? Playing Croquet on the back lawn of an estate? Wooo-Woo. Most of the planet that I have seen is in a struggle just to stay alive a little longer. Billions for headphones and a strategy? Most of the world describes this as a mental illness condition.

THx-RNMarsh
 
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DVV, the first question imo would be, how does it measure.

Up to, or better than nominals specs. Not one item below specs, which are reasonable, not outlandsih, although for that time (1979-1982), I suppose they were well above the norm in their price class.

At first, I thought it was spitting at me because the electrolytic caps were 30+ years old and probably way off nominal. So they were repalced, all of them, with identical values, by caps from Fisher & Tausche and BC Components (which is itself owned by Philips, I am told).

This caused the sound to come to better focus, but it was still spitting, not as shrill as before, but still wrong.
 
These 'deals' come with a lot of conditions.... you get this and that - if we get this or that. Sort of like the sports 'figures'. IF they win every game and the super-duper final play-off can they make top dollar. So, lok at the guarenteed minimum number instead... or what the stock part of the payment is currently worth. etc. A lot of conditions..... but its still a lot.

I have seen and followed the careers of a few who are mulit-millionares. I now define Richa s people who worked for it and if they stopped working, the money would soon stop as well. I define wealthy as those who are rich whether they work at it or not... like super rich = wealthy. Such as those who are born into wealth and never will have to work. Rich. wealthy. I would go nuts being wealthy (bored) if I couldnt be actively involved in doing something with the wealth.... maybe like Gates...... kept mentally involved and busy. And, I'm only retired and it is easy to get bored. W.Buffet understands this about being rich or wealthy..... there are a limited number of things to play with... bigger or more homes, cars, boats/Yachts and airplanes. larger, better A-V gear/room? Thats all there is. Oh, and shoes. Then what? Playing Croquet on the back lawn of an estate? Wooo-Woo. Most of the planet that I have seen is in a struggle just to stay alive a little longer. Billions for headphones and a strategy? Most of the world describes this as a mental illness condition.

THx-RNMarsh

You get bored? That'll be the day!

Richard, NOBODY here even knows what it means to be really bored, I suspect. 2-3 days of loitering about and we get the shakes. By day 3, we're all good junkies, looking for our soldering irons for a fix at something. Or we just brainstorm. Or whatever, but we do NOT sit around idle.
 
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