Overengineering in audio equipment

Class A has no overall current swing, so it's easier to filter for. RC filer is cheap and works well... LC even moreso, but you have to find the "critical" values otherwise it doesn't really work.
:up:

Yes. I linked it earlier.
sorry 😱 Got one ! thanks a lot 🙂

It will be above 14kHz unless it's a real slice of crap.
😀

For your pleasure: I spoke about the SE MOSFET amp I'm listening to... Here's the recipe (schematic). Yes, LS1 is a pair of 200W incandescent light bulbs acting as the load resistance... It could be replaced with 18R/100W resistor, but more expensive that way. And this way you get free light!
I have issues with tubes ... they need two Vsupply one of which very high voltage Maybe in the future I can understand why people love tubes especially when i listen to choirs ... voices are very beautiful through tubes
But i have also listened great voices with transistors. 😉
Thanks a lot again for the advice on smps. :up:
 
Thanks a lot I know that site very well. I will study the schematic you mention. Do you think that the design could be scaled down to serve as a high performance line stage ? maybe i have found what i am looking for

I suppose, but it's not a trivial circuit.

i am all ears ... requirements single supply 😱 few parts, V gain of 2-3 times, good driving ability to be usable with any power amp around

I was talking about a power amp kit.

Simple, 2 or 3 transistor line stages can be found on the Elliot Sound Products website, somewhere. Elliott Sound Products - The Audio Pages (Main Index) His stuff is geared towards advanced hobbyists and some of it is really good. I've used bits and pieces of his circuits in my designs and builds. He even sells boards and detailed instructions for some of his projects.

Pick a simple project you like and build it. I guarantee you'll learn a lot, especially if you do it from scratch. Can you make circuit boards? Do you have access to solderable prototype boards? You can build a lot of line level circuits on boards like this SB404 BusBoard Prototype Systems | Mouser and this POW3U BusBoard Prototype Systems | Mouser .
 
I suppose, but it's not a trivial circuit.
i see :up:

I was talking about a power amp kit.
ok. Actually my understanding is that many very popular integrateds have just a volume pot in front of the power amp stage with no line preamp 🙄
Maybe that is the way ? to skip on the line preamp ?

Simple, 2 or 3 transistor line stages can be found on the Elliot Sound Products website, somewhere. Elliott Sound Products - The Audio Pages (Main Index)
His stuff is geared towards advanced hobbyists and some of it is really good.
Thanks a lot for the link. I am sure i would pick the shortest stick ... 😱🙁
Sometimes i see experts judging the quality of a circuit just looking at the schematic ... like they have a simulator in the brain. They are geniuses indeed. 😱

I've used bits and pieces of his circuits in my designs and builds.
He even sells boards and detailed instructions for some of his projects.
Pick a simple project you like and build it. I guarantee you'll learn a lot, especially if you do it from scratch.
i am sure ... but first i have to select the right one. That is the problem.

Can you make circuit boards?
😀 obviously not ... i have just desoldered and soldered parts Actually i was the champion of cold joints before discovering the magic solder ... the Sn62/Pb36/Ag2
I know ... it is toxic ... but it is just fantastic It flows like anything else
Wonderful. I was even thinking to buy a protective mask in order to be able to keep on using it ... i adore this alloy.
And i also love desoldering ... but the pump i was using was cheap.
I love when i flip over a board desolder and the parts just fall like ripe fruits 🙂
I have a maintenance guy inside ... i feel it

Do you have access to solderable prototype boards? You can build a lot of line level circuits on boards like this SB404 BusBoard Prototype Systems | Mouser and this POW3U BusBoard Prototype Systems | Mouser
Thanks a lot. Very convenient boards indeed. But i need the schema first.
Actually i would like some sim first. But i would like to find a book/user guide for LTSpice specifically intended for slightly retarded people 😱
Seriously something as basic as possible. A user guide with very little theory. I do not think it exists 🙁
Thanks a lot again.
 
Actually my understanding is that many very popular integrateds have just a volume pot in front of the power amp stage with no line preamp 🙄
Maybe that is the way ? to skip on the line preamp ?


Up to you. I use a full feature preamp.

Sometimes i see experts judging the quality of a circuit just looking at the schematic ... like they have a simulator in the brain. They are geniuses indeed.

Experience.

And i also love desoldering ... but the pump i was using was cheap.
I love when i flip over a board desolder and the parts just fall like ripe fruits

Try desoldering braid.

But i would like to find a book/user guide for LTSpice specifically intended for slightly retarded people

I never used it. I learned a long time ago to do it all by hand. There was no SPICE when I went to school and Al Gore hadn't invented the internet yet. No PCs, basic engineering calculator over $200, we had to punch cards and wait a day for the results of our program.

Thanks a lot again.

You're welcome. Hope it helps.
 
Up to you. I use a full feature preamp.
Experience.
I see. It takes competence and experience.

Try desoldering braid.
Tried it ! not for me i am afraid

I never used it. I learned a long time ago to do it all by hand. There was no SPICE when I went to school and Al Gore hadn't invented the internet yet. No PCs, basic engineering calculator over $200, we had to punch cards and wait a day for the results of our program.

I see. I have just the feeling that it is a very powerful tool. My new obsession is stability first and PSRR second
By the way i do not understand why they name it PSRR Power Supply Rejection Ratio ... and N for Noise ? i think that it should be PSNRR ?

You're welcome. Hope it helps
For sure and thank you sincerely for sharing your knowledge with me and providing very helpful advice.
Have a nice day 🙂
 
I prefer SN62 myself.

Good morning Mr Curl and thank you very much indeed for your kind and valuable advice. I guess you are referring to this one ?

https://aimsolder.com/sites/default/files/alloy_sn62-pb36-ag2_tds.pdf

Maybe i am overestimating the importance of the alloy to be used but as i said above i have a very heavy hand with soldering iron and cold joints were the norm. After discovering this alloy the soldering activity has become a joy ...
Unfortunately very good soldering irons are available for peanuts also with T control. Instead desoldering electric pump starts from 100 USD (debatable quality) with the very good ones very expensive. But i love them. I like to replace all the old alloys with a fresh new one. Sometimes even resolder some joints can provide benefits (not sure about this by the way).
In particular when i will retire i would love to restore simply old hifi that no one cares about
I have a trash bin friend ... it is impressive what he finds sometimes
The new generations do not feel the same love for hifi of older generations
What a pity.
Thanks for sharing your valuable knowldege with us at Diyaudio.com
Kind regards,
gino 🙂
 
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Good morning everyone 🙂
during the weekend in a vintage hifi site I found some posts by an engineer who has been a member of the Nikko design team in the golden days of the company
He said among other things that all in all the amp that sounded cleaner at the time it was the Nikko Alpha III of which I report a schematic (not very readable i am afraid)
This has quite convinced me that even simple designs can produce great sound but also about the opportunity to use opamps.
Many designers still consider them to be something not really suitable for hifi. But there are examples that seem to say the opposite. 🙄
 

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