Your having illusions of persecution.
Perhaps a ' more miserable than thou ' complex ....
I was just interested on what you guys thought about this circuit. And I got answers. No affront was intended. I do think simple is better too; When I saw that beast of a servo I was taken aside.
You guys are serious about this, right? I'm on a different planet I'm afraid.
Tums up for you Scott, at this moment I'm listening to FM on my 604's with a pair of extra mid range horns with the help of a 85W Parasound amp. Sounds good to me, but naturally I have good tuners , one good FM station and a good glass of red wine.
Not quite sure about your point, do you find $200 capacitors necessary in your system? BTW the best sound I ever heard was over FM with totally ordinary gear.
Approx. this is my point.
FM suppose to sound good, according to colonel Armstrong.
No fancy capacitors for me, beyond the ordinary styroflex.
My current living room is not small, but I am satisfied by couple of 12" woofers in concrete boxes, and one concrete horn subwoofer under the floor that uses also a pair of 12" drivers. The reference is DVD and blue ray movies. Running horses and earthquakes feels quite real. What else to wish? However I can put few 18" drivers under the floor, but what about walls and ceiling, what are their resonant frequencies? Do I need to follow realism of destruction of houses in the movies I watch?
I personally have never found any value in going over 6" in a woofer. I hate bass reproduced by a speaker, it always sounds artificiial to me except at the most extreme implementations.
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I sort of disagree, size is matters. The 15" ones has body.
My upstairs "system" has a pair of 6" Audax woofers and also a 12" sub, but the 604's sounds better. The effortless sound of the Altec's is very pleasing.
By the way, how are you reproduce bass?
Could the "body" from your 15" woofer really be second and third harmonic distortion? Very few musical instruments have any output below 40 Hz and even heavy rap stops at 60 Hz. Flat response from a woofer is relatively easy. Getting low distortion and real output below 60 Hz is much harder.
This is not the place to get lost in a discussion of woofers. However how the preamp (blowtorch) handles the low frequencies at and below the audio band can affect the presentation. If you model the system it has a series of high pass filters starting with the microphone and ending with the speaker-room interaction. Any given stage can be fairly benign but 4 cascaded high Q rolloffs within a part of an octave could have a pretty odd peak-dip response (like a head bump?).
I built a phono preamp with flat response to DC. Curiously, it was less prone to acoustic feedback than the conventional variation with a 5 Hz rolloff. Possibly less phase shift at the possible feedback frequencies? (That would be sheer dumb luck and change with the weather.) However it has a much different bass quality that I really liked.
This is not the place to get lost in a discussion of woofers. However how the preamp (blowtorch) handles the low frequencies at and below the audio band can affect the presentation. If you model the system it has a series of high pass filters starting with the microphone and ending with the speaker-room interaction. Any given stage can be fairly benign but 4 cascaded high Q rolloffs within a part of an octave could have a pretty odd peak-dip response (like a head bump?).
I built a phono preamp with flat response to DC. Curiously, it was less prone to acoustic feedback than the conventional variation with a 5 Hz rolloff. Possibly less phase shift at the possible feedback frequencies? (That would be sheer dumb luck and change with the weather.) However it has a much different bass quality that I really liked.
I usually design to 'win' listening contests. I don't start with 'junk' and expect to get the best sound possible. Of course, how much I have to invest in caps depends partially on the seriousness of the project. Best in world, possibly? Compete favorably with anything shown at CES or The Show? Appreciated by audio reviewers? Maybe, all three.
However, I just use servos, and THEN I don't have to use $200 caps, and I still win the listening contests.
It is important to see how 'easy' it is to add servos, and REMOVE coupling and large value feedback caps, and still get virtually no DC offset. This was the point of the whole exercise.
However, I just use servos, and THEN I don't have to use $200 caps, and I still win the listening contests.
It is important to see how 'easy' it is to add servos, and REMOVE coupling and large value feedback caps, and still get virtually no DC offset. This was the point of the whole exercise.
Servos do add more parts and everything imparts some sonic quality or another. No cap is best but 100dB on a phono stage doesn't even like to be breathed on and you have to play well with others so a servo makes good technical sense if you want to ship product. It also takes less board space if you have the supplies already.
Measure the group delay of the entire system. A typical all tube system at that. Then you will see the benefit of direct coupled circuits.
A wise guy!
No a 'typical' tube system. It will self explain why the bass sounds better with ss amps and dc-coupled ones in particular.
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The Sonic Frontiers Line series of balanced tube preamps used a unique tube constant current source differential tube input stage with only a 0.22 uf (tft teflon with a .01 bypass in mine) interstage coupling cap between the input differential and the split supply (+126/-126 VDC shunt regulated) actively loaded cathode followers. The cathode follower output stage is DC servo controlled and uses no output coupling cap.
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