I just intend to use smaller values with relatively slower output devices. That's all. I hadn't serious listening tests for C12.. I think their purpose more related with stability issues.
Ken's soft clipper applied to my amplifier in the picture of post #657, well, this:
It got some additional experimentation today, with a lot of different combinations. And much like Edison's 1000 ways not to make a light bulb I discovered quite a few ways not to make a soft clipper. Failures included a bass remover (courtesy of bat86), a hard clipper (when the soft clipper is set too aggressive), a burglar alarm (constructor error), acutance ringing (screaming midrange if 470R is shorted) or a complex device (that does absolutely nothing).
But, after a lot of patience, there was one upgrade that worked.
See the inversely parallel 1n914 clipper at in+ and see the voltage divider (in place of R16 at in-) in that picture with the 470R in-between? I added inversely parallel pair of 1n5819 in parallel to that 470R. It was to see if two decent results could work together, and they did. NICE!!!
That slight change is very similar results to the photo, less clipping, slightly clearer, bigger soundfield size. However, the amplifier now sounds "fresher" and cleaner (super loud russian triode on regulated power kind of sound?) and even bigger soundfield--up to 6 foot wide, 21 foot long soundcast from a single speaker. The clipping performance is much like the original unaltered amplifier's clipping performance, except with more x-max and no significant clipping. I like it a lot!
The really clean presentation applies whether it is cranked up loud or playing quietly. Perhaps a very small amount of feed forward is going on, but I do not know.
It is nice that a 45 watt amplifier can easily do much more, although there is still no explanation for audio power like wind that most 45w amplifiers don't do. Fascinating! Now it is time to build more sturdy speakers.
P.S.
These results are with the Post#1 Circlophone only slightly modified with different output device and driver, with R17 at 20k, and with R21/D8/D9 set to support 31v rails.
It got some additional experimentation today, with a lot of different combinations. And much like Edison's 1000 ways not to make a light bulb I discovered quite a few ways not to make a soft clipper. Failures included a bass remover (courtesy of bat86), a hard clipper (when the soft clipper is set too aggressive), a burglar alarm (constructor error), acutance ringing (screaming midrange if 470R is shorted) or a complex device (that does absolutely nothing).
But, after a lot of patience, there was one upgrade that worked.
See the inversely parallel 1n914 clipper at in+ and see the voltage divider (in place of R16 at in-) in that picture with the 470R in-between? I added inversely parallel pair of 1n5819 in parallel to that 470R. It was to see if two decent results could work together, and they did. NICE!!!
That slight change is very similar results to the photo, less clipping, slightly clearer, bigger soundfield size. However, the amplifier now sounds "fresher" and cleaner (super loud russian triode on regulated power kind of sound?) and even bigger soundfield--up to 6 foot wide, 21 foot long soundcast from a single speaker. The clipping performance is much like the original unaltered amplifier's clipping performance, except with more x-max and no significant clipping. I like it a lot!
The really clean presentation applies whether it is cranked up loud or playing quietly. Perhaps a very small amount of feed forward is going on, but I do not know.
It is nice that a 45 watt amplifier can easily do much more, although there is still no explanation for audio power like wind that most 45w amplifiers don't do. Fascinating! Now it is time to build more sturdy speakers.
P.S.
These results are with the Post#1 Circlophone only slightly modified with different output device and driver, with R17 at 20k, and with R21/D8/D9 set to support 31v rails.
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Can you clarify that what is the aim of these alterations? Are these only applicable if using such 22K/470R gain ratio? Or, are you trying to satisfy nfb respecting that high gain? Do you recommend those modifications for gain setting around 30db?
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It changes somewhat the aspect of the open loop transfer function.
The effect on the closed loop response is infinitesimal, and should not be audible.
2n2 is still safe, but going much further could begin to cause instabilities.
He's tuning the knee of his clip to personal taste and voltage headroom.
I think I tuned upon the assumption of 24V rails. Dan's rails are higher.
The aim is to clip something simple and open loop that recovers quicker
than if clipping were to occur within an amplier's closed loop. A soft clip
is also theoretically reversible. Information is distorted in a soft clip, but
not lost. This often sounds less objectionable than a hard clip where
information is smashed flat against a brick wall. And/or cumulative error
improperly "fixed" long after the fact. I don't think Elvee's amp suffers
delayed fix prob, was more in-general gripe about run of the mill clips.
We soft clip to the opposite side of the LTP rather than GND to get a
better feel if the amplifier is handling the situation fine, or needs help.
That way we aren't clipping quite so much more than necessary. It
moves the knee up, and allows for greater linearity below the knee.
Its also more tunable than a stack of grounded diodes of fixed drop.
I would have just tuned the ratio of resistors that make R16. But Dan
might have prefered the sound with a Schottky knee? It is certainly a
different curve than the junction diode alone.
I think I tuned upon the assumption of 24V rails. Dan's rails are higher.
The aim is to clip something simple and open loop that recovers quicker
than if clipping were to occur within an amplier's closed loop. A soft clip
is also theoretically reversible. Information is distorted in a soft clip, but
not lost. This often sounds less objectionable than a hard clip where
information is smashed flat against a brick wall. And/or cumulative error
improperly "fixed" long after the fact. I don't think Elvee's amp suffers
delayed fix prob, was more in-general gripe about run of the mill clips.
We soft clip to the opposite side of the LTP rather than GND to get a
better feel if the amplifier is handling the situation fine, or needs help.
That way we aren't clipping quite so much more than necessary. It
moves the knee up, and allows for greater linearity below the knee.
Its also more tunable than a stack of grounded diodes of fixed drop.
I would have just tuned the ratio of resistors that make R16. But Dan
might have prefered the sound with a Schottky knee? It is certainly a
different curve than the junction diode alone.
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The aim of the alterations is improved sound quality. That's what the added circuit is for. I'm sure that you will find it easy and well worth your time, except if your amplifier is far more powerful than you need, then the soft clip circuit would not switch on. As Ken mentioned, soft clip recovery is possible. Here is one option to remove/reduce compression of recordings.
I have attempted to modify Ken's circuit to imitate a triode sound.
They are applicable for 31v rails. For more or less, adjust the R16 voltage divider that is shown on the schematic below.
Well I think that there must be a good reason that you make a power amplifier with gain instead of a large buffer without. As for gain settings you'll want to proof your computer source with free RightMark Audio Analyzer since everything may be just fine until the computer source has to push dynamics. You can have cleaner output (avoid blaring) by having either a preamplifier or Circlophone perform some of the amplification duties and not run the computer source out of headroom for either voltage or current. The easy fix is to turn the computer up only as far as sounds good and then set your gain for the difference so that you can make clean use of your power amplifier's potential.
Applied:
After checking six different sound chips and four different sound cards, I got 20k for R17 (when amp has 31v rails) except for an M-Audio Audiophile that has two paralleled JRC4580 onboard preamplifiers and then R17 at 15k worked in that case. The simplest possible solution for a modern source pushing a power amp larger than ~17w, is gain in proportion to power, which is Very dynamic, whereby you might appreciate the soft clip circuit which activates only when needed, such as realistic replay of a concert with only a medium size solid state power amp.
Opportunity cost applies. My apologies for the quality control outage earlier--Instead of relying on a confusing mess of text that wasn't clear, I should have created a small clean schematic, focused to the point.
This accessory is a potentially desirable integrated amplifier component.
Here it is:
Attachments
So Daniel, I'm also using 31V rails and I'm listening at very moderate levels rather..maybe I can't reach 10W even. Is it worthy to fight with dynamic range of recordings anyway in these conditions?
I slightly modified that one with doing some cosmetics at power rails side. Also, its altered version has a fuse doughter board (Elvee's optimal protection layout) pads at output. An additionally wire jumper which closing feedback loop will make it one version for all.
And I didn't share my version of powerflux's pcb yet
I slightly modified that one with doing some cosmetics at power rails side. Also, its altered version has a fuse doughter board (Elvee's optimal protection layout) pads at output. An additionally wire jumper which closing feedback loop will make it one version for all.
And I didn't share my version of powerflux's pcb yet
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I suggest you get into contact with member Mickeymoose: he has already produced a very nice beta version (see somewhere in the previous posts), and he is in the process of preparing the final one.
I am sure he could take on board any sensible or desirable feature/improvement, including soft clip, etc.
In my opinion, Mickeymoose's pcb is too much complete for some diyers here including myself. Frankly, I have to say that I prefer well designed and approved bare pcb solutions. Hope you don't count me as negatively criticizing. I respect all efforts done in diy spirit.
terran: no affront taken in your comments, but you seem to contrdict yourself (somewhat)
My original take on the C was that there is a design that suits me, I would like to listen to.
Than I decided what the needs are for my home system (2, 2+1, 4+1, and so forth) and how to best implement that
I will post the Gerber files for my layout and a partslist of specialized parts next week, the amp circuit pcb design is basically that of post #1. Use my pcb layout at your own peril
I had a great deal of fun doing this and thank Elvee for his patient input to the pcb design. I learned many a detail of pwramp design (he claims he does not how to do pcb's, I do not believe that any more!))
As Captain DYIAudio would have said: "Go boldy forward, build and listen!" E
PS: Capt. Kirk and Capt. DIYAudio are both Canadians! E
My original take on the C was that there is a design that suits me, I would like to listen to.
Than I decided what the needs are for my home system (2, 2+1, 4+1, and so forth) and how to best implement that
I will post the Gerber files for my layout and a partslist of specialized parts next week, the amp circuit pcb design is basically that of post #1. Use my pcb layout at your own peril
I had a great deal of fun doing this and thank Elvee for his patient input to the pcb design. I learned many a detail of pwramp design (he claims he does not how to do pcb's, I do not believe that any more!))
As Captain DYIAudio would have said: "Go boldy forward, build and listen!" E
PS: Capt. Kirk and Capt. DIYAudio are both Canadians! E
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You're using a Ferrari for cruisin main? My application is more like a Winnebago roaring to climb the Albuquerque pass, battling the wind, and flying past the 18 wheelers on the way UP. So, there's a similar amount of torque available in both cases, but our usage is somewhat different. Even so, the topic is input and neither application works optimally with water in the fuel tank. It is merely more noticeable in one application than the other.
Since I couldn't possibly answer no, the answer is yes (to quality input). The concept that I just can't seem to explain (but this is not your fault at all), is that you don't want your system artificially topped out. I think that you don't want it to sound loud unless it really is. You want to remove compression, hard sound, limiting, blare, distortion, clipping and noise from the source in order to do something better instead: Back in the old days, recordings were quite dynamic and the vacuum tube power amplifier would apply soft clip rarely and only as needed; so, when it wasn't at the top, all other music information is presented with concert realism.
Alternative answer: The cost for 4 diodes and 3 resistors to nicely accommodate a decently recorded track, probably costs less than just one track.
At least I can say that it is worth the price. A knee voltage is not really a sharp wall so even at lower playback there may be a bit of action and remember that diode switch on can occur with ac+dc voltage. As an unintended bonus, it blocks some spurious noise and since diodes are capacitive, the ~5pF might assist stability slightly, which may also be audible. So, generally, yes it is well worth your time to interview that inexpensive little soft clip accessory. As far as I know, many tiny steps in generally the right direction is what makes a hi-fi amplifier. I really do appreciate your skills, so perhaps you can take what I've done and make it even better. I think the circuit assists clarity, even at a few watts, and so I would greatly appreciate a second opinion.I like your upgraded "RF resistant" model that was based on a "known good" (wakibaki) and has been performing so very well and reviewed to do so. I greatly favor all of that, because what I need at this time is a nice sturdy baseline.
I have developed a filter accessory for the input that reduces compression from the source. It is the inverse partner to the soft clip. The BlareBuster circuit helps manage compressed tracks and both circuits work together without interference. In order to create this integrated amplifier piece tuned specific to Circlophone, I need a reliable baseline PCB for power amplifier that is already proofed and also uncomplicated.
A rock solid baseline baseline power amplifier is a must and so much like having a road map for a trip. Being that apartments and communities everywhere are choked with RF pollution, I would choose Terranigma's board as the most likely head start, since Chicago radio style layout has built in RF management and consequently stability benefits. It is identifiable although I've never seen that done with split rail and single layer board. And I believe that the wider spacing may help keep resistor drain applications cooler, even without a fan. The only problem is that I've never manufactured circuit boards and do not know how to do it.
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That's all fine, but I'm searching for availability and it isn't.
P.S.
The soft clip is very easy to add top-side and then the overload stopper with the zeners can go trackside right under the 10k input load. So, it doesn't matter if the PCB has dedicated spots for these or not. But, they don't fit existential PCB, since that is not solid. So, there is a slight problem.
P.P.S.
The DIYab amp project also had a lot of trouble in getting available boards. It is still on existential PCB at this time, but a more solid form is scheduled for about 6 weeks from now. Let's go a bit faster than that, just for sport.
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I think that there is a misunderstood maybe my English.. It is obvious that your approach is very different and most complete when comparing with other ones. What I need was an amplifier pcb somewhat make you deal with bare amplifier itself, just like those ones I had struggle with. This is my approach and nothing to do with different ones.
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Yes, you seem well describe my point of view. I'm also a purist. I like simple but effective solutions. I think that Circlophone has cured what all the things suffered and vastly struggled with thermal tracking, crossover distortion and biasing issues with BJTs. These are huge problems in solid state audio business. Maybe that's the why you feel necessary to mention "triode sound" of your Circlophone.
I have also discovered that pre-eighties recordings are showing their real qualities easily. Loose representation that appeared as vocals and instruments are on same layer has gone and new layers added to representation. Despite my variety of experiments, I count myself as being at very early stage.
Alternative answer: The cost for 4 diodes and 3 resistors to nicely accommodate a decently recorded track, probably costs less than just one track.
My concern was totally out of cost. I wasn't sure about that degrade something that I already have while trying to gain something that I never need for. Your comments are fair enough for decide what to do.
Actually It is not that "RF resistant" as I faced with my tests so far. Still some RF noise interfering to my gear. I'm still investigating the reason of my first build. One of something to do is closely imitating that one.
It would be an outstanding success if could deal with my terrific environmental RFI noise. Idea of avoiding volume pot and connecting my DAC's analogue pins directly to amp requires such quietness. I have read a document that shared one topics here that describing why software volume control degrades dynamic range of recordings. But I'm not sure that it is true with latest digitally attenuated dac chips like mine (AK4396). I should decide it for myself.
This clipper is of zero direct relevance to a circlophone,
would "work" or distort terribly for any LTP front end.
It has become a distraction, lost all touch with the OP.
Sorry, I didn't foresee this result before I tacked it onto
one of my schematics.
I have posts of questionable relevance here that I would
defend as quite relevant. This clipper wasn't one of them.
would "work" or distort terribly for any LTP front end.
It has become a distraction, lost all touch with the OP.
Sorry, I didn't foresee this result before I tacked it onto
one of my schematics.
I have posts of questionable relevance here that I would
defend as quite relevant. This clipper wasn't one of them.
Effects Box
The only other thing I have to say about it is:
Thank you.
As an effects box, it is a highly malleable harmonics adjustment device that could be set to benefit Television/MP4/AAC/HDradio and the Realtek sound chip or anything else that could use a fresh little harmonics boost. And 20 cents is still a bargain price for a job that's impossible to do with an eq.
The only other thing I have to say about it is:
Thank you.