Hi ! it is the first time i see this ... i'd call it crowded ? 🙄🙂
Not what i thought ... i read something like taking out pieces and get better sound that surprised me. When i see signal transformers i think always to Neve preamps. Maybe that is what consumers liked ? the sound through signal transformers ? i do not know. Today i deal only with files streaming and usually i rip all my cds. It is easier and the sound can be pretty decent.
Thanks for the interesting pics. Never seen them before.
@ginetto61
that's a discrete active tone stack and there's no redundancy there, it make sure that impedance adaptation with input and output will be perfect with any input and any power amp. I really like it, including the bootstrap used in the second stage. Can you please tell me the source of this schematic?
look at this one too:
https://www.diyaudio.com/forums/ana...apacitor-induced-distortions.html#post6298349
that's a discrete active tone stack and there's no redundancy there, it make sure that impedance adaptation with input and output will be perfect with any input and any power amp. I really like it, including the bootstrap used in the second stage. Can you please tell me the source of this schematic?
look at this one too:
https://www.diyaudio.com/forums/ana...apacitor-induced-distortions.html#post6298349
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hi ! thanks for the valuable advice. I have no answer ... as usual 😱🙁
i know of people listening big and demanding speakers with pro amps that i guess are very standard design ... it seems to me that the difference between one and another is the quality of parts used like better transformers and passive components
Also because many companies copy schematics from US famous brands i am afraid ... 😡 .. using maybe even fake caps
may i ask you what is for you a better performance ? or better do you check that by listening to the amp ?
"Overengineering" is a concept without context in the normal process of product development. It implies that engineers loop into endless cycles of product development adding complexity and content without regard to anything but their engineering whims. It doesn't work that way, at least not in my experience.
The stage at which the content and complexity of the end product is actually controlled is when the product specifications are agreed upon. These can be as straightforward as the overall size and weight of the target product, as complex as it's detailed performance specifications, as unavoidable as the regulatory standards to which it must comply and be certified, as uninteresting to an end consumer as the capital available for manufacturing facilities, and as all important as the sales price and profitability targets..
Once the requirements are established the role of the product engineers is to find a solution that best satisfies this matrix of requirements working in collaboration with colleagues in varied disciplines like purchasing, manufacturing, product certification, marketing and distribution and finance.
The DIY process where an individual iterates a design with total control until it satisfies his or her own peculiar desires without exceeding his or her own budget has nothing whatsoever in common with the engineering of a commercial product in the real world of business.
The stage at which the content and complexity of the end product is actually controlled is when the product specifications are agreed upon. These can be as straightforward as the overall size and weight of the target product, as complex as it's detailed performance specifications, as unavoidable as the regulatory standards to which it must comply and be certified, as uninteresting to an end consumer as the capital available for manufacturing facilities, and as all important as the sales price and profitability targets..
Once the requirements are established the role of the product engineers is to find a solution that best satisfies this matrix of requirements working in collaboration with colleagues in varied disciplines like purchasing, manufacturing, product certification, marketing and distribution and finance.
The DIY process where an individual iterates a design with total control until it satisfies his or her own peculiar desires without exceeding his or her own budget has nothing whatsoever in common with the engineering of a commercial product in the real world of business.
https://www.vintageshifi.com/repert...p?pdf=Radford-HD-250-ZD-22-Service-Manual.pdf
i said badly ... the signal is forced to pass more components and run the risk of alterations ... that can be small enough but still is not like a bypass jumper
I am focusing the line output stage ... i wonder if this stage would be ok even with power amps with low Zin (like 5kohm) and higher capacitance (like 1000 pF or so)
A push pull like in the Rotel preamp should be stronger ?
I and a friend tested his power amp with my old Bryston and his tube preamp ... with the tube preamp the bass was much less defined and powerful he was badly surprised by this performance His preamp is much more expensive than the Bryston, of course Like 4 times more ...
often engaging the CD direct function on some amps improves sound and measurements.
A good reason to avoid tone controls i would say 🙄 ... and i save you a very rude freudian joke ... 😱
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i'm not going to comment on all the schematics you throw at me...the tone section looks competent enough.others might have an idea...
A Paul Kemble web page - the Radford HD250 and ZD22 amplifiers.
A Paul Kemble web page - the Radford HD250 and ZD22 amplifiers.
sorry ... do not tell me that you use tone controls ... i cannot believe that
Who here is using tone controls ? this is insane ...
Who here is using tone controls ? this is insane ...
Sounds like the coupling caps are too small to me. That or the tube preamp was designed to drive a tube amp with 100k Zin.
A common mistake I see is people designing for 20Hz instead of 2Hz when using a first order filter. You need to design for a -3 of 2Hz to have flat response from 20Hz up.
My tube designs put out 5 Hz easily if you want them to.
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Nooo ... stop it 😱 how i would have liked to get Freud's opinion on tone controls lovers ... 🙄😀
Seriously i have seen somewhere a SW test ... with tone controls engaged the response of the DOT was worse than with them bypassed 🙂
It was a Conrad Johnson pv10 ... i see 2 or 4uF output cap depending on the version ? this is interesting because the midrange with the tubes was much nicer ... with voices and so on. But the bass was weak and out of control. S
i am sure of this ... but i really would like to stay solid ... i just would like to understand what makes a sound good or not But i am about to give up ...
ok i should have said not needed
I had in the past some units just with a volume control ... i did not miss the tone controls at all
I would be very curious to know the percentage of people here who really use tone controls ... maybe i am the only one despising them 😱
Amplifiers can have features like this too. An example is active current limiting of the output devices, which is a very common feature. This adds at least six components to the mix, including two transistors. And it also will intrude on the performance of the amplifier, but a well sorted circuit won't intrude until you want it to.
Also Doug Self showed a Vbe multiplier circuit that controls current bias drift better than the usual configurations. It uses one more resistor than usual.
It's not that simple. In your example, a proper statistical analysis of the failure modes would take into consideration the actual tension in the individual strands. A similar consideration would have to be given to the design of an amplifier. Example - paralleling power resistors increases parts count but increases long term reliability. This is a direct analogy to your number of strands in a rope model.
My point is that it's not true in a "way statistically" because basing reliability on parts count alone is a flawed model. I know you realize this.
"I would be very curious to know the percentage of people here who really use tone controls ... maybe i am the only one despising them"
I see nothing wrong with an amelioration of a recording deficiency.
"It's not that simple."
Of course there is an infinity to the depth to which study can be done, I'm not suggesting that what I stated was an entire treatise on the subject.
I see nothing wrong with an amelioration of a recording deficiency.
"It's not that simple."
Of course there is an infinity to the depth to which study can be done, I'm not suggesting that what I stated was an entire treatise on the subject.
I do not doubt this - but this is no real argument for a general statement that sound a bit religious to me. The touch of absolute truth is it what provokes responses like mine was.😉
Your grandfather who's a music lover, can't hear anything over 10khz and you want to impress him with a new record with silky highs...
Nor did I. As a BT apprentice I was told this was done with the old dial telephones, it was designed then components were removed to see if it still worked. It was a very efficient design with many common circuit elements having different functions simultaneously and at different times
ok i should have said not needed
I had in the past some units just with a volume control ... i did not miss the tone controls at all
I would be very curious to know the percentage of people here who really use tone controls ... maybe i am the only one despising them 😱
I was referring to your overall approach not just tone controls.