Alas, we do seem to be a pretty intolerant bunch. Perhaps I should say we can be.
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Not really infinite. You need to determine what factors are relevant and analyze them. A practical analysis ignores trivial factors.
And in the end, you could still be wrong.
It's happened. Tacoma Bridge - YouTubeHello there,
My take on "overengineering" a device and tone controls.
1. When I build something I use devices that are quite over rated for the application. Costs very little more and makes for very long lived projects.
2. Not needing tone controls: Best tone controls IMHO have a switch that completely bypasses them. Can not do any harm if they are not even in the circuit unless you want / need them in.
Also, some seem to adjust for tone by changing speakers. Incredibly expensive and hard way to do this. And what happens when you get a record or CD that is different from most? Get new speakers. Just nuts.
My take on "overengineering" a device and tone controls.
1. When I build something I use devices that are quite over rated for the application. Costs very little more and makes for very long lived projects.
2. Not needing tone controls: Best tone controls IMHO have a switch that completely bypasses them. Can not do any harm if they are not even in the circuit unless you want / need them in.
Also, some seem to adjust for tone by changing speakers. Incredibly expensive and hard way to do this. And what happens when you get a record or CD that is different from most? Get new speakers. Just nuts.
Not really infinite. You need to determine what factors are relevant and analyze them. A practical analysis ignores trivial factors.
And in the end, you could still be wrong.
I of course deal with what are current relevant factors, but it's a personal view that reality is infinite; I haven't seen much to refute that.
A practical analysis in a sphere which is progressive towards perfection, will eventually have to deal with supposedly "trivial factors' as the other greater ones of currently high significance, are eliminated.
I like that stance starkeyg.
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Hi ! just to say that i like this. It sounds very smart to me. Often i read about failure of parts used very close to the boundaries of their soa ...
They are pushed to their limits i mean ... better to be safe than sorry.
Especially when alternatives are available.
i was referring to the cd direct option present in some integrateds that bypasses tone controls and sometimes even balance ?
For instance i took out the balance control in a preamp ... i read that balance can increase crosstalk between channels ?
Usually the sound is cleaner with cd direct engaged. I prefer more transparent sound. Even if at the beginning can seem harsher ...
As an aside i also read often that in the units with pre-main separation usually the power amp section is at least decent, power requirements satisfied
What seems lacking is the preamp (i am talking of solid state only). The very good sounding SS preamps seem rare.
i have been recommended to select speakers first. Then power amp able to drive properly those speakers. Some speakers are very demanding in terms of amplification. Some amps even caught fire i understand.
So the matching is critical.
If tone controls are used to flatten the FR i really think that a 2 frequencies tone control is not enough.
I have no experience with EQ ... that is much complex thing and i guess it works ok.
Imhe the worst enemy for a great playback are uncontrolled walls sound reflections
Just think of listening in a reverberant room ... i guess i would get crazy. 😱
Instead i wonder if in an anechoic room the virtual soundstage would be very good indeed ??? never tried it of course
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And thank God this is The Longue ... where people are supposed to discuss amiably while drinking a cup of tea ... 🙄
i cannot immagine in the other sections ...
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Of course. And this often leads to an increase in parts count.
Agree, but the nature of the 'catastrophe' depends on the configuration of the components, and sometimes parallel ccts can eliminate this by 'takover'.
"Hi ! just to say that i like this. It sounds very smart to me. Often i read about failure of parts used very close to the boundaries of their soa ...
They are pushed to their limits i mean ... better to be safe than sorry.
Especially when alternatives are available."
I always do that, even for an 8W 240V light I have used 10A junction boxes.
"What seems lacking is the preamp (i am talking of solid state only). The very good sounding SS preamps seem rare."
Benchmark, or my own ATC SCA2?
"i have been recommended to select speakers first. Then power amp able to drive properly those speakers. Some speakers are very demanding in terms of amplification. Some amps even caught fire i understand.
So the matching is critical.
If tone controls are used to flatten the FR i really think that a 2 frequencies tone control is not enough.
I have no experience with EQ ... that is much complex thing and i guess it works ok.
Imhe the worst enemy for a great playback are uncontrolled walls sound reflections
Just think of listening in a reverberant room ... i guess i would get crazy.
Instead i wonder if in an anechoic room the virtual soundstage would be very good indeed ??? never tried it of course"
Agree, choose speakers on their own merit using best possible ancillaries, then choose best possibel power amp for those speakers.
Graphic eqauliser might be useful, and LEDE is used; certainly a little reverb around the stereo pair is better than completely dead.
They are pushed to their limits i mean ... better to be safe than sorry.
Especially when alternatives are available."
I always do that, even for an 8W 240V light I have used 10A junction boxes.
"What seems lacking is the preamp (i am talking of solid state only). The very good sounding SS preamps seem rare."
Benchmark, or my own ATC SCA2?
"i have been recommended to select speakers first. Then power amp able to drive properly those speakers. Some speakers are very demanding in terms of amplification. Some amps even caught fire i understand.
So the matching is critical.
If tone controls are used to flatten the FR i really think that a 2 frequencies tone control is not enough.
I have no experience with EQ ... that is much complex thing and i guess it works ok.
Imhe the worst enemy for a great playback are uncontrolled walls sound reflections
Just think of listening in a reverberant room ... i guess i would get crazy.
Instead i wonder if in an anechoic room the virtual soundstage would be very good indeed ??? never tried it of course"
Agree, choose speakers on their own merit using best possible ancillaries, then choose best possibel power amp for those speakers.
Graphic eqauliser might be useful, and LEDE is used; certainly a little reverb around the stereo pair is better than completely dead.
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I see 🙂 and failures can also cause big damages ... like fire and so on.
Good to know. The ATC it is very nice ... which Benchmark are you referring at ?
like an halo ? uhmm ... not convinced completely
I like razor sharp images ... extreme detail ... very seldom (and the recording and the room are very important to get this effect) it seems like the players with their instruments materialize in the room
The ears tell me that they are here but i do not see them ... i love listening in the dark ... the feeling to be transported for instance in the place where the event has occurred
Very magical
Don't know the model numbed of the Benchmark, my friend has that and the AHB2 and the D2A. Their specs are stunning.
This thread has brought up some horrible memories of when I had to do reliability calculations using MIL-217F. I am going to have to get horribly drunk to bury them again 😛
Good morning just a speedy question ... design complexity and stability are correlated in any ways ?
i mean ... more complex designs are more likely to be also stable ? if so this is a very important issue.
I had a bad experience trying to decrease the gain of a power amp stage replacing the FB resistor with a smaller value one
... i ruined the amp and burned my hand touching the heatsink that got extremely hot.
I remember the circuit board starting vibrating and fumes from the mains transformer ... when the ignorance meets the stupidity
i mean ... more complex designs are more likely to be also stable ? if so this is a very important issue.
I had a bad experience trying to decrease the gain of a power amp stage replacing the FB resistor with a smaller value one
... i ruined the amp and burned my hand touching the heatsink that got extremely hot.
I remember the circuit board starting vibrating and fumes from the mains transformer ... when the ignorance meets the stupidity
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you said that before...the amp is essentially an op-amp and making it unity gain stable is a challenge for any engineer.
Practical Techniques to Avoid Instability Due to Capacitive Loading | Analog Devices
Practical Techniques to Avoid Instability Due to Capacitive Loading | Analog Devices
i guess that we can call any amp stage = discrete op-amp broadly speaking
Of course i was not pretending to make a many stages amplifier a buffer 😱 just reducing it gain a little ... but without know how i ended in a disaster and i also hurt myself
When a high gain is needed i am expecting more stages and complexity and this is perfectly fine to me
It is a unity gain buffer with tenths of active devices that is more difficult for me to digest
Ok i have to study electronics ... but i would need a book that does not go too much in depth with calculation but just provides some principle ... like gain vs. stability ... how to get the PSRR vs. Hz of a amp stage ... distortion can be seen with sim i understand
I would say that the very difficult issues to understand are stability and PSRR
I was reading the paper by Nelson Pass on his project for DIYers the Bride of Zen. Some statements are very understandable for me but other less ...
For instance the reason why to go single ended i understand ... the nature of sound is single ended ... there is only air push ... not air pull
Then the decision for a zero feedback design ... that i understood less
I did not even understand how to calculate the stage gain ... he explained it by i got confused
And there are opamps that provide same gain and much lower distortion and higher PSRR
Still many think that the BOZ sounds much better than a op-amp line stage and i listened to it and actually loved it. I still have somewhere ... i am in a mess these days
And i have this modding vice ...
For instance the BOZ stage gain is around 6 ? then i would like to be able to decrease the gain to 2
I also would like to reduce the +60 Vsupply voltage to 48V (i would like to use a little Meanwell smps i bought. It is very cute and a moderator suggested that it can be very good because the switching Hz are very beyond 20kHz ... noisy but with a noise spectrum placed completely outside the audio range. This psu has a MTBF of almost 1 million hours or 111 years ... i just could not pass on it)
Unfortunately i cannot do even these just that very basic mods
But without ending with a broken circuit or unstable possibly 😱🙁
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Thanks !!! just bought it 🙂 hoping to understand a little 😱
I would like just to add that if they show that a more complex design improves some parameters like PSRR or slew rate or decrease distortion i would be more quiet ...
But if another designer comes ... take out parts, modifies the circuit and ends with better parameters/sound ? does that makes him a genius ? for me not only a genius ... but a gift to the human kind. 🙄
Life is already so complex ... we do not need more complexity i think
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