EMI generated from my Eigantakt Class D Amplifier

[Atmasphere]

Granted, we all discern/interpret what we hear differently. But personally, I’m hearing some overly bright, overly detailed, thin/lean, slightly compressed, congested, boxy/roomy bass, and a touch of digital-like hash in one of these videos — very similar to traits Class D and even digital owners have been complaining about for 20+ years. But I’ll leave it to you and others to decide which.

I hear that on all online videos and have never taken any of them seriously. All the video says to me is that someone felt it was worth doing for a reason so I take them as statements on that account only.

As you know this was in the room of the reviewer, who gave the amps a good review. There's a good deal of other reviews out there; one of them makes comparison to our M-60 OTLs which that reviewer also reviewed. The M-60s have garnered many reviews and awards in the high end press over the years and decades. Its probably a good idea to not draw conclusions until you have direct experience.

There are two other class D amps which you might also want to hear if you even plan to give class D another chance. One is the AGD which looks a bit like a box with a KT88 mounted to it. The other is the Orchard class D. Both use GaNFETs, which allow for vastly reduced switching noise due to less inductive parasitics.

 

[Alrainbow]

Class d is fine it’s very much like other Amps it needs to paired to speakers that play well with it period
let’s put aside any noise claims from the amp on line side power. It’s not heard and If
It is well there are other fish to fry.
now having said this the ones I’ve heard that look like they have a glowing tube
Ganfet I think a few brands sounded good to my brain no system is perfect nor any device in the chain.
but careful paring makes for a good sound
there are some facets of class d that are good and yes some not so good
But Any amp has this.
if you like boulder do you also like gryphon
I’m guessing no lol.
do you like transistors or mosfet
not the same sound right
be it class d or class A or class ab none sound the same.
to say a class d amp is bright with broad brush is an opinion not a fact.
OTL have there place but must be paired with a speaker that allows for a low damping factor and an imp that matches as well.
The thread is about one person who claims without any evidence says it’s the amp making noise in a tweeter. This I can understand but the rest becomes a blind pile on of opinions not based on facts .

ralph may not make amps I love but he does make products that others do love rightly so too.
He has to take his time to reply on this thread to correct or at least attempt to correct facts.
not fair in my world in audio there are plenty of Huber expensive products that don’t sound good to me and even if they are paired with other Huber expensive products either.
I love the sound of tube set amps but not for a speaker setup but headphones
So am I missing something or is this just a choice

 

[stehno]

I hear that on all online videos and have never taken any of them seriously. All the video says to me is that someone felt it was worth doing for a reason so I take them as statements on that account only.

As you know this was in the room of the reviewer, who gave the amps a good review. There's a good deal of other reviews out there; one of them makes comparison to our M-60 OTLs which that reviewer also reviewed. The M-60s have garnered many reviews and awards in the high end press over the years and decades. Its probably a good idea to not draw conclusions until you have direct experience.

There are two other class D amps which you might also want to hear if you even plan to give class D another chance. One is the AGD which looks a bit like a box with a KT88 mounted to it. The other is the Orchard class D. Both use GaNFETs, which allow for vastly reduced switching noise due to less inductive parasitics.

lol. If you really believe in-room videos have zero credence, why share one with me — and why did you not say so at the time?

You must have thought Tim's video had at least some value, otherwise why would an amp designer point to a “worthless” video of his own designs in action?

Were you hoping I wouldn’t notice the numerous "malfunctions" in Tim’s playback? Or did you simply not notice the “me too hi-fi” type of sound yourself? Either way, what exactly was your point in posting the video?

I’m reminded of your own line: “most of this is nonsense.” I agreed then — but I agree even more now.

BTW Ralph, I’m not here to pass judgment on your amps. For all I know they may be stellar performers.

My point is much simpler. No component and no system is ever truly complete without some type of superior (as opposed to inferior) AC purification. That goes for all but especially for Class D and Digital components. Ignore the root cause, and all we can ever do is chase symptoms / effects.

 

[Atmasphere]

If you really believe in-room videos have zero credence, why share one with me

Because you asked.

You must have thought Tim's video had at least some value, otherwise why would an amp designer point to a “worthless” video of his own designs in action?

In this case, it had the value of providing a video of what you asked for. Beyond that, no. But it might again if someone else asks.

Were you hoping I wouldn’t notice the numerous "malfunctions" in Tim’s playback? Or did you simply not notice the “me too hi-fi” type of sound yourself?

I've not heard it myself. Like I said, I don't take online videos seriously since there is no way to judge what you're hearing. I suspect you'll hear those same 'malfunctions' in most any video though due to confirmation bias which affects us all.

My point is much simpler. No component and no system is ever truly complete without some type of superior (as opposed to inferior) AC purification.

That was not your point earlier but since you brought it up I'm mostly in agreement. However I'm also of the opinion that most so-called 'power conditioners' offered to high end audio are so much junk. To really be an effective conditioner, the unit must be able to suppress harmonics of the line frequency (the 5th harmonic is known to be particularly pesky) and also regulate line Voltage without limiting current up to the limit of the conditioner. Most 'conditioners' offered to high end audio cannot do these things. The PS Audio is one of the few that can.

There is a company called Elgar that made AC conditioners long ago. They could do the things I described above and more. Elgar got out of that market a long time ago so if you find one of their conditioners it will have to be refurbished.

But here's an interesting tidbit: the more feedback the amplifier uses, the less susceptible to AC line problems it can be because the feedback allows it to reject that which is not the signal. For the most part, the amps with the most feedback are class D amps of the self-oscillating variety, since the oscillation is caused by an excessive amount of feedback being applied- exceeding the amplifier's phase margin. But the feedback loop is designed to only allow one oscillation frequency, and that frequency is used as the switching frequency. Due to their efficiency, such amps tend to be the least affected by the AC line.

By contrast, our OTLs draw quite a lot of power due to the class of operation and the filament circuit. They are also low or zero feedback, so they are affected by the AC line (mostly the line Voltage since they are quite good at rejecting AC line noise due to their differential operation).

If you have a zero feedback circuit in a preamplifier and then have good regulation with good overhead, then the AC line noise and Voltage won't be an issue.

 

[stehno]

Because you asked.

In this case, it had the value of providing a video of what you asked for. Beyond that, no. But it might again if someone else asks.

I've not heard it myself. Like I said, I don't take online videos seriously since there is no way to judge what you're hearing. I suspect you'll hear those same 'malfunctions' in most any video though due to confirmation bias which affects us all.

That was not your point earlier but since you brought it up I'm mostly in agreement. However I'm also of the opinion that most so-called 'power conditioners' offered to high end audio are so much junk. To really be an effective conditioner, the unit must be able to suppress harmonics of the line frequency (the 5th harmonic is known to be particularly pesky) and also regulate line Voltage without limiting current up to the limit of the conditioner. Most 'conditioners' offered to high end audio cannot do these things. The PS Audio is one of the few that can.

There is a company called Elgar that made AC conditioners long ago. They could do the things I described above and more. Elgar got out of that market a long time ago so if you find one of their conditioners it will have to be refurbished.

But here's an interesting tidbit: the more feedback the amplifier uses, the less susceptible to AC line problems it can be because the feedback allows it to reject that which is not the signal. For the most part, the amps with the most feedback are class D amps of the self-oscillating variety, since the oscillation is caused by an excessive amount of feedback being applied- exceeding the amplifier's phase margin. But the feedback loop is designed to only allow one oscillation frequency, and that frequency is used as the switching frequency. Due to their efficiency, such amps tend to be the least affected by the AC line.

By contrast, our OTLs draw quite a lot of power due to the class of operation and the filament circuit. They are also low or zero feedback, so they are affected by the AC line (mostly the line Voltage since they are quite good at rejecting AC line noise due to their differential operation).

If you have a zero feedback circuit in a preamplifier and then have good regulation with good overhead, then the AC line noise and Voltage won't be an issue.

lol

Thanks for substantiating all of my points, Ralph. Sorry it was never my intention to be entirely at your expense. That was your doing.

 

[Atmasphere]

lol

Thanks for substantiating all of my points, Ralph. Sorry it was never my intention to be entirely at your expense. That was your doing.

Your position is not supported by anything I've said.

I have simply stuck to facts and despite the digs, not risen to baiting.

For example, while you might not have liked what you heard in the video, you don't know why that actually is (conformation bias is high on the list after the discussion we've had); its a bit of a stretch to say its the noise you've been mentioning without actual proof of it. There are far too many variables!

Many such videos are recorded on a phone. In this recording we don't know the recording equipment although I'm sure I could find out easily. For your conclusion to hold any water at all, the recording system (and the YT algorithms to compress data) have to be assumed to be 100% without fault. Quite simply, its not.

That is why I don't take YT videos seriously; and that doesn't even include variables such as the room, speakers and front end components used. But apparently you do take YT videos seriously (at least this one); which leads me to conclude that you have come to a hasty generalization. Being a logical fallacy, such is false by definition. Its an easy mistake to make.

I understand how switching noise is a problem just so we're clear. I have an inexpensive but highly reviewed (based on specs only) DAC (Topping D30) in my basement system. FM reception is not so good when its on; you can pick up 'noise stations' that are not there when the DAC is off. As you know DACs are not high power. But if one of our class D amps sits in the same position in that system, the FM works fine.

 

[stehno]

Your position is not supported by anything I've said.

I have simply stuck to facts and despite the digs, not risen to baiting.

For example, while you might not have liked what you heard in the video, you don't know why that actually is (conformation bias is high on the list after the discussion we've had); its a bit of a stretch to say its the noise you've been mentioning without actual proof of it. There are far too many variables!

Many such videos are recorded on a phone. In this recording we don't know the recording equipment although I'm sure I could find out easily. For your conclusion to hold any water at all, the recording system (and the YT algorithms to compress data) have to be assumed to be 100% without fault. Quite simply, its not.

That is why I don't take YT videos seriously; and that doesn't even include variables such as the room, speakers and front end components used. But apparently you do take YT videos seriously (at least this one); which leads me to conclude that you have come to a hasty generalization. Being a logical fallacy, such is false by definition. Its an easy mistake to make.

I understand how switching noise is a problem just so we're clear. I have an inexpensive but highly reviewed (based on specs only) DAC (Topping D30) in my basement system. FM reception is not so good when its on; you can pick up 'noise stations' that are not there when the DAC is off. As you know DACs are not high power. But if one of our class D amps sits in the same position in that system, the FM works fine.

lol. Somehow I’m reminded of the old TV game show, “What’s My Line?”

You posted the video, Ralph, not me. If your youtube video is worthless now, then it was just as worthless when you offered it as evidence. Can’t have it both ways.

The truth is, your video wasn’t worthless at all. It was quite telling as it pretty much confirmed what 20+ years of listener reports, including my own experiences, have shown: Class D’s bi-directional digital-like noise doesn’t vanish just because someone waves it off as “already pretty low” or rebrands it as RFI or a malfunction.

As for confirmation bias, that sword cuts both ways, partner. With 20+ years of consistent listener complaints with various systems, rooms, and brands, not to mention my own experiences and simple experiments, brushing it all off as confirmation bias appears to be just another way of avoiding the obvious.

BTW, two can play this game. For I too solved the Class D bi-directional noise issue 15 years before you with my then superior Foundation Research passive, dedicated, bi-directional filtering line conditioners without ever having to pop the top. From the sound of things, with my even slightly more superior Jena Labs dedicated, passive, and bi-directional filtering line conditioners, that same remedy still comes out the clear winner. See either of my videos posted above and compare to your own.

Repeat after me… Long live superior line conditioners, especially the bi-directional filtering kind.

 

[Atmasphere]

You posted the video, Ralph, not me. If your youtube video is worthless now, then it was just as worthless when you offered it as evidence. Can’t have it both ways.

The truth is, your video wasn’t worthless at all. It was quite telling as it pretty much confirmed what 20+ years of listener reports, including my own experiences, have shown: Class D’s bi-directional digital-like noise doesn’t vanish just because someone waves it off as “already pretty low” or rebrands it as RFI or a malfunction.

As for confirmation bias, that sword cuts both ways, partner. With 20+ years of consistent listener complaints with various systems, rooms, and brands, not to mention my own experiences and simple experiments, brushing it all off as confirmation bias appears to be just another way of avoiding the obvious.

BTW, two can play this game. For I too solved the Class D bi-directional noise issue 15 years before you with my then superior Foundation Research passive, dedicated, bi-directional filtering line conditioners without ever having to pop the top. From the sound of things, with my even slightly more superior Jena Labs dedicated, passive, and bi-directional filtering line conditioners, that same remedy still comes out the clear winner. See either of my videos posted above and compare to your own.

Repeat after me… Long live superior line conditioners, especially the bi-directional filtering kind.

I didn't make or post the video, as I explained earlier. Clearly you've not been reading my posts. That makes it very difficult to have a conversation of any merit.

'Bi-directional noise' does not exist in engineering. There is a concept of reducing noise at the source and receiving end which is known as 'bi-directional noise reduction' or cancellation. Clearly somebody or somebodies were/are confused and/or ignorant when creating the term 'bi-directional noise' as something that exists on its own.

Its unfortunate when others take up the torch for the non-existent thing.

You can't solve a problem that does not exist as it has a lot in common with dividing by zero. Since your post is founded on two logical fallacies, that of limited sample size and the oft-used strawman, it is false by definition.

 

[PYP]

I find my Mola Mola amps to be very transparent. When I've read a few reviews of the MM amps and other very low distortion amps like Audionet (which are not Class D), some of the comments made me wonder whether the reviewer understood that they were probably hearing their upstream components rather than the amps themselves.

This transparency can present a challenge to getting the sound to your liking (assuming that the amp is well-suited to your speakers). One needs to understand how each upstream component impacts the sound.

Class D has been greatly improved since PS audio offered the HCA-2 "digital" amplifier (circa 2000 I believe). That amp showed the promise of transparency, but something was lacking. I believe Bruno Putzeys paved the way for the modern Class D.

 

[stehno]

I didn't make or post the video, as I explained earlier. Clearly you've not been reading my posts. That makes it very difficult to have a conversation of any merit.

'Bi-directional noise' does not exist in engineering. There is a concept of reducing noise at the source and receiving end which is known as 'bi-directional noise reduction' or cancellation. Clearly somebody or somebodies were/are confused and/or ignorant when creating the term 'bi-directional noise' as something that exists on its own.

Its unfortunate when others take up the torch for the non-existent thing.

You can't solve a problem that does not exist as it has a lot in common with dividing by zero. Since your post is founded on two logical fallacies, that of limited sample size and the oft-used strawman, it is false by definition.

lol. You’re all over the frickin’ map here with your doublespeak, doublethink, wish fulfilment, spin, claims, denials, etc.

Talk about nonsense.

We’re done here, Ralph. Thanks for playing.

 

[treitz3]

Ouch.

Tom

 

[Atmasphere]

lol. You’re all over the frickin’ map here with your doublespeak, doublethink, wish fulfilment, spin, claims, denials, etc.

Talk about nonsense.

We’re done here, Ralph. Thanks for playing.

You're welcome.

I think you know the accusation of 'doublespeak' or the like is really weak. If not, go back and look at my prior posts and you'll see I've been consistent. For example I provided the link to the video but not the video itself. I am guessing(?) you didn't notice it was was posted by a reviewer from Positive Feedback, Tim Aucremann. Thus my denial about posting it is not an example of doublespeak innuendo.

I've been consistent with my comments about technical issues. I recommend you google 'bi-directional noise'; you'll see what you are up against.

As I pointed out early on during these missives, 'bi-directional noise' is simply noise. Its not something unique to class D or digital circuits. What is, as I posted earlier, common to those two technologies is noise artifacts that arise from switching and those tend to show up due to parasitic inductances which are able to oscillate. I've mentioned that several times. I feel like you ignored that.

You might consider actually designing a class D or digital circuit rather than attempting to preach to someone who has already done so.

 

[Republicoftexas69]

lol. You’re all over the frickin’ map here with your doublespeak, doublethink, wish fulfilment, spin, claims, denials, etc.

Talk about nonsense.

We’re done here, Ralph. Thanks for playing.

Thank God!