I must say I do like to reminisce, so much new techniques back then, a real age of progress!
In here there is a note about how a higher distortion amplifier design methodology sounded better, as the focus moved to higher slew rates and better phase margins - ignoring THD which rose.
http://www.nutshellhifi.com/library/tinyhistory2.html
Hi JeyDee,
Completely disagree. However there isn't any law preventing you to setting up things to your personal taste. But if it isn't accurate, it isn't high fidelity (by definition).
A reproduction system reproduces the mix as recorded by the engineer in the studio. Period. Can you change it? Sure.
Completely disagree. However there isn't any law preventing you to setting up things to your personal taste. But if it isn't accurate, it isn't high fidelity (by definition).
A reproduction system reproduces the mix as recorded by the engineer in the studio. Period. Can you change it? Sure.
Define "musical" 😄
In my book, pianos, violins, organs, human voice are Musical.
Amplifiers amplify.
Guitar amps are a very different breed and not what we are talking here.
If so personal, why even mention it in a 500000 member site?
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A musician I knew said something interesting about Hifi..
He said:
"Good music transcends the medium"
I.e. if it's good, it shouldn't matter what you listen to it on!
Since then I listen to the music rather than the hifi.
But still seek purer ways to design the HiFi !
He said:
"Good music transcends the medium"
I.e. if it's good, it shouldn't matter what you listen to it on!
Since then I listen to the music rather than the hifi.
But still seek purer ways to design the HiFi !
Yes. It happened to be the connectors on my speaker wires.
It's very much better now.
You can smell them leaking from a mile away. They are bad.
Some kind of pot metal or something hidden underneath the gold colored covering.
It was the source of the bad sound.
Hi TheSoundMann,
Okay, then you can't run the amp at all. Those caps are non-functional as far as providing clean power. You should mention these things early. In fact, sound quality may be suffering greatly just due to that factor.
The power supply must be working properly before you can assess an amplifier (or anything for that matter). You are wasting your time until you fix these caps.
Normally (except for really cheap caps, or very hot ambients), filter capacitors have higher quality seals and a lot more electrolyte. They can last many decades without problems. You can test them easily by looking at the ripple waveform across the capacitor. I rarely have to change them in good equipment. Early multi-section capacitors are a little different due to technology and extreme age. Smaller electrolytic capacitors are far more problematic, the ones with wire leads. The seals aren't nearly as good.
For speaker terminals, the best would be either barrier strip types (like old tube amps), or brass binding posts, the industrial ones. They are rated 15 or 30 amperes normally and you can get them as dual. Gold plating is not very good. Banana plugs are not the best connection either. Spade terminals, or the round ones (I cut out a passage near the side to pass the post through). They can't be easily pulled off either, you'll end up with an amp on the floor if you try.
-Chris
Okay, then you can't run the amp at all. Those caps are non-functional as far as providing clean power. You should mention these things early. In fact, sound quality may be suffering greatly just due to that factor.
The power supply must be working properly before you can assess an amplifier (or anything for that matter). You are wasting your time until you fix these caps.
Normally (except for really cheap caps, or very hot ambients), filter capacitors have higher quality seals and a lot more electrolyte. They can last many decades without problems. You can test them easily by looking at the ripple waveform across the capacitor. I rarely have to change them in good equipment. Early multi-section capacitors are a little different due to technology and extreme age. Smaller electrolytic capacitors are far more problematic, the ones with wire leads. The seals aren't nearly as good.
For speaker terminals, the best would be either barrier strip types (like old tube amps), or brass binding posts, the industrial ones. They are rated 15 or 30 amperes normally and you can get them as dual. Gold plating is not very good. Banana plugs are not the best connection either. Spade terminals, or the round ones (I cut out a passage near the side to pass the post through). They can't be easily pulled off either, you'll end up with an amp on the floor if you try.
-Chris
The only caps currently available that fit this amp without modifications are United Chem-cons.
Are these going to be sufficient?
Are these going to be sufficient?
They are genrally good in my experience and when you have issues like this I find it helpful to be able to measure and look at the noise floor, THD, IMD etc. If your main caps are shot you may have massive amounts of PS harmonics on the supply rails which would find its way to the output and add distorsion to the signal.
A reasonable good USB interface/soundcard goes a long way.
I had a terrible problem with sound in one of my systems, thought the speakers were blown!
Turned out that the line RCA connectors has become very slightly and invisibly corroded (in a dry, inland house!!).
The solution was switch cleaner, plug them in again and wiggle, and both channels recovered perfectly.
So as a matter of course a big upgrade for many could be to simply use switch cleaner/oil on contacts and sometimes work them a little.
United Chem-con capacitors are pretty good in fact.
Replace those and start over with assessing it. Do not increase the capacitance, but go higher in voltage if they are too small.
Replace those and start over with assessing it. Do not increase the capacitance, but go higher in voltage if they are too small.
The mains caps are 18,000uf @ 75v x4. I ran it for 4 hours today upside down with the bottom cover off.
The amp produced so little smell that it was difficult to tell where it is coming from. But I do believe that one of the big caps is responsible for it.
Also, one of the amp boards is running a bit warmer than the other.
The amp produced so little smell that it was difficult to tell where it is coming from. But I do believe that one of the big caps is responsible for it.
Also, one of the amp boards is running a bit warmer than the other.
Even though I corrected the original complaint about the sound, it is still too revealing for my taste.
I require a warmer and smoother amp.
I require a warmer and smoother amp.
I still don't think you are going about this the right way. First fix power the supply caps, all of them. Then let's start looking at the rest of your system, including all the ground loops, before going down some track that isn't going to fix some of the audible problems you are probably finding distasteful.
BTW, do you have a good HPA and good headphones? Do you have an alternate power amp, or can you borrow one? IOW, I'm trying to figure how to tell how much of the problems can be attributed to the power amp and not the rest of the system.
BTW, do you have a good HPA and good headphones? Do you have an alternate power amp, or can you borrow one? IOW, I'm trying to figure how to tell how much of the problems can be attributed to the power amp and not the rest of the system.
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I have had zero sonic issues with other amps in this system, which includes my headphone rig.
Both my Accuphase E-202 and my Sony ES receiver have performed here without issue, if you overlook their lack of damping factor.
I am currently looking to purchase an Onkyo M-282 to fill in while I sort out the problems with the amp in question.
Both my Accuphase E-202 and my Sony ES receiver have performed here without issue, if you overlook their lack of damping factor.
I am currently looking to purchase an Onkyo M-282 to fill in while I sort out the problems with the amp in question.
As as experiment, what happens if you connect a 100R non-inductive resistor across each of your speaker terminals?
Maybe something like this: https://www.mouser.com/ProductDetai...MIsYThwqqOhAMVrhCtBh3zWgXhEAQYBCABEgLrrfD_BwE
Maybe something like this: https://www.mouser.com/ProductDetai...MIsYThwqqOhAMVrhCtBh3zWgXhEAQYBCABEgLrrfD_BwE
Well, for the bass modules of my Acoustat Spectra 11's, a damping factor of 50 is not enough to properly control them.