What do you guys think of the newly released Nobsound E6?

[TrippRyder]

Negative feedback is or was not the problem with class D amps, it's the disharmonic noise that it generated in older models. The IC's were noisy, the smps was not as advanced as now used and so added noise, and disharmonic noise is very disturbing. It needs to be below 100dB to be not disturbing for me in a hifi situation and untill the birth of the first NCore, it was not that low. W

ith a class A amp, and less degree a class AB amp, the noise can be much higher as the strongest noise that masks the rest is harmonic, and low harmonic. And those enchange the sound and create the "warmth" and "life" (actually low harmonic distortion), that TrippRyder misses in class D amps and claims comes from negative feedback.

Negative feedback can reduce dynamics of music by smearing it, but the ammounts fof negative feedback that is needed for that is far beyond what is typically used in amps. It's not that that takes away what you want. It's the lack of harmonic distortion that disturbs you. I also prefer harmonic distortion btw, but real clean class D amps like the NCore or Purifi amps can also appeal to me. And i prefer very low disharmonic distortion in my "harmonic distortion amps", so this Nobosound is crap to me (to return to the original topic). And yes, i have one of the older models.

I never mentioned Class D amps.

Ever heard a Class A tube amp\preamp that uses a cathode follower in the circuit? It absolutely squashes the sound, and it is essentially 100% nfb. Not Class D, not A\B, a Class A Triode tube. No thanks, but hey, it measures great!

So without seeing test results or hearing the E6 for yourself, you claim it to be "crap" because you guess it has high disharmonic distortion?

This post keeps getting better and better! So much slander and shit talking about a preamp that most of you havent heard, have very little knowledge of, and are biased against because of its cost and origin.


Did any of you notice the writing on the circuit board "Rev. 5.0"? Hmm, maybe theyve done some tweaking before releasing the product.......


It MAY measure terribly. Time will tell. I just find it ridiculous that on a page called Audio Science Review there are so many bigoted opinions.

 

[fpitas]

I never mentioned Class D amps.

Ever heard a Class A tube amp\preamp that uses a cathode follower in the circuit? It absolutely squashes the sound, and it is essentially 100% nfb. Not Class D, not A\B, a Class A Triode tube. No thanks, but hey, it measures great!

So without seeing test results or hearing the E6 for yourself, you claim it to be "crap" because you guess it has high disharmonic distortion?

This post keeps getting better and better! So much slander and shit talking about a preamp that most of you havent heard, have very little knowledge of, and are biased against because of its cost and origin.


Did any of you notice the writing on the circuit board "Rev. 5.0"? Hmm, maybe theyve done some tweaking before releasing the product.......


It MAY measure terribly. Time will tell. I just find it ridiculous that on a page called Audio Science Review there are so many bigoted opinions.

I hate to ask. But a triode has tremendous inherent electrostatic NFB from anode to grid, yet I guess that's OK?

 

[TrippRyder]

I hate to ask. But a triode has tremendous inherent electrostatic NFB from anode to grid, yet I guess that's OK?

Can you define "tremendous"?

"Inherent electrostatic NFB from anode to grid"

Thats news to me. I'll look into that, but if thats the case, and its "inherent" as you say, that is far different than adding a NFB or a GNFB loop into a circuit.

Perhaps thats partly why Triodes tend to be more linear than Tetrodes and Pentodes?

 

[fpitas]

Can you define "tremendous"?

"Inherent electrostatic NFB from anode to grid"

Thats news to me. I'll look into that, but if thats the case, and its "inherent" as you say, that is far different than adding a NFB or a GNFB loop into a circuit.

Perhaps thats partly why Triodes tend to be more linear than Tetrodes and Pentodes?

Well, yes. And why the plate resistance is so small. And why Miller capacitance is of concern.

 

[antcollinet]

Can you define "tremendous"?

"Inherent electrostatic NFB from anode to grid"

Thats news to me. I'll look into that, but if thats the case, and its "inherent" as you say, that is far different than adding a NFB or a GNFB loop into a circuit.

Perhaps thats partly why Triodes tend to be more linear than Tetrodes and Pentodes?

If that is news to you - then how do you know the inherent feedback isn't doing exactly the same as an added circuit? How do you know it is different at all let alone far different. Or are you just making up your assumptions as you go?

 

[TrippRyder]

Well, yes. And why the plate resistance is so small. And why Miller capacitance is of concern.

Are you talking about actual Triodes or Triode strapped Pentodes, or?

 

[fpitas]

Are you talking about actual Triodes or Triode strapped Pentodes, or?

Either. Triode strapping gives a device remarkably like a regular triode.

 

[TrippRyder]

If that is news to you - then how do you know the inherent feedback isn't doing exactly the same as an added circuit? How do you know it is different at all let alone far differenet. Or are you just making up your assumptions as you go?

Do you know that it is fact?

Im not the one making brash statements and mass assumptions in this thread.

 

[TrippRyder]

If that is news to you - then how do you know the inherent feedback isn't doing exactly the same as an added circuit? How do you know it is different at all let alone far different. Or are you just making up your assumptions as you go?

Click the link, the "thumbnail" it shows is not what im trying to share.

Triode plate resistance == internal negative feedback?

On another thread I posted an aside as a addendum to a otherwise on topic technical contribution: ...it is hard to not comment on ... several swipes at negative feedback: use enough closed loop gain in a negative feedback amp with only smooth, low order nonlinearities and you get decreasing...

www.diyaudio.com

 

[A Crabb]

So the E6 had to use something like this to boost the voltage. If you look in between the tube sockets, you can see the top of a small coil's bobbin.

There have to be parts on the bottom of this board.

My E6 should be here Friday. I'll pop it apart and post pics.

Attached Files:​

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[TrippRyder]

Amcrabb, just more eye candy, or is there some sort of text that should go with this?

 

[TrippRyder]

I just got mine hooked up today. Certainly IS microphonic. Considering the design of the chassis, its not a surprise.

The tube sockets have some play and wiggle if you reach in and push on them.

The sockets are laying right on the fibreglass circuit board, no isolation of any kind, and the circuit board is held in place by sliding into grooves milled into the aluminum outer casing. Then the milled aluminum outer casing's milled aluminum ends are screwed into place.

Mine had considerable hum until i wiggled the tubes around and found a "sweet spot" where they made better connection. While i was wiggling the front tube the led backlighting the tube turned off and on......

Despite this, once i got it settled in, i was quite happy with how it sounds. Better than 2 well reviewed preamps i have and better than the Schiit SYS i have.

I think im going to take it back apart and resolder the tube sockets to the board, touch up some other joints, add some foam dampers in between the board and the casing, and clean the tubes pins.

Maybe after l listen to another CD or two.....

 

[A Crabb]

Amcrabb, just more eye candy, or is there some sort of text that should go with this?

Just showing a view of the coil you spoke of.

I’m sorry to hear of the microphonics you were experiencing. I still have not experienced any.

 

[Cbdb2]

Negative feedback can reduce dynamics of music by smearing it, but the ammounts fof negative feedback that is needed for that is far beyond what is typically used in amps.

You'll have to prove that one, sounds like audiophool bs. The only problem with too much FB is instability and that is easily dealt with.

From Bruno Putzeys The F-wordor, why there is no such thing as too much feedback

https://linearaudio.net/sites/linearaudio.net/files/volume1bp.pdf

 

[Cbdb2]

Can you define "tremendous"?

"Inherent electrostatic NFB from anode to grid"

Thats news to me. I'll look into that, but if thats the case, and its "inherent" as you say, that is far different than adding a NFB or a GNFB loop into a circuit.

Perhaps thats partly why Triodes tend to be more linear than Tetrodes and Pentodes?

Feedback is feedback, inherent or not. Again, read The f-word. And just so you know Bruno did not make this up himself, its been known in control system engineering for 80 years. Why do audiphools think audio electronics is special and dosnt conform to standard electronic theory and design?

 

[fpitas]

Feedback is feedback, inherent or not. Again, read The f-word. And just so you know Bruno did not make this up himself, its been known in control system engineering for 80 years. Why do audiphools think audio electronics is special and dosnt conform to standard electronic theory and design?

At a guess because they are ignorant of control theory, too?

 

[Talisman]

It continues to amuse me that "audiophile" tube amps are progressing backwards with time. For 50 years the best and brightest strived for minimal distortion. Now, they're special effects boxes trying to capture the dulcet tones of an old 5-tube radio

Why does it seem strange to you? But even more, why does it seem to bother you so much as if it were a personal offense?
In the years in which acoustic fidelity was lacking it is clear that the minimum possible distortion was sought with the technologies of the time, nowadays, in which audio electronics is practically a problem overcome even with very cheap equipment, we try to give some ' of that distortion that makes music pleasant to some.
But if you don't like it, nobody forces you to buy it or use it,
what's the point of asking to send one to Amir to measure it? We all know very well what we get, tons of harmonics, high distortions and 40db sinads, what do you want to prove? that a small Chinese box with two tubes won't play hi-fi? Do we need Amir's test to know that?
This is a game, a nice little box that might smooth out the sound in a small secondary or tertiary setup, presumably plugged into equally cheap little amps. I don't think anyone intends to use it between a 1000 euro dac and a purifi power amp connected to kef R7s.
So the question is, why this ferocious harassment against these cheap little products? We know what they are, we know what they do, they don't try to sell them for thousands of euros pretending it's true high fidelity, it's an honest product. I think there are other enemies to defeat in the audio world.

 

[fpitas]

Why does it seem strange to you? But even more, why does it seem to bother you so much as if it were a personal offense?
In the years in which acoustic fidelity was lacking it is clear that the minimum possible distortion was sought with the technologies of the time, nowadays, in which audio electronics is practically a problem overcome even with very cheap equipment, we try to give some ' of that distortion that makes music pleasant to some.
But if you don't like it, nobody forces you to buy it or use it,
what's the point of asking to send one to Amir to measure it? We all know very well what we get, tons of harmonics, high distortions and 40db sinads, what do you want to prove? that a small Chinese box with two tubes won't play hi-fi? Do we need Amir's test to know that?
This is a game, a nice little box that might smooth out the sound in a small secondary or tertiary setup, presumably plugged into equally cheap little amps. I don't think anyone intends to use it between a 1000 euro dac and a purifi power amp connected to kef R7s.
So the question is, why this ferocious harassment against these cheap little products? We know what they are, we know what they do, they don't try to sell them for thousands of euros pretending it's true high fidelity, it's an honest product. I think there are other enemies to defeat in the audio world.

I'll admit it seems like a degression to me. But I didn't spend several paragraph about it, either

 

[Cbdb2]

Why does it seem strange to you? But even more, why does it seem to bother you so much as if it were a personal offense?
In the years in which acoustic fidelity was lacking it is clear that the minimum possible distortion was sought with the technologies of the time, nowadays, in which audio electronics is practically a problem overcome even with very cheap equipment, we try to give some ' of that distortion that makes music pleasant to some.
But if you don't like it, nobody forces you to buy it or use it,
what's the point of asking to send one to Amir to measure it? We all know very well what we get, tons of harmonics, high distortions and 40db sinads, what do you want to prove? that a small Chinese box with two tubes won't play hi-fi? Do we need Amir's test to know that?
This is a game, a nice little box that might smooth out the sound in a small secondary or tertiary setup, presumably plugged into equally cheap little amps. I don't think anyone intends to use it between a 1000 euro dac and a purifi power amp connected to kef R7s.
So the question is, why this ferocious harassment against these cheap little products? We know what they are, we know what they do, they don't try to sell them for thousands of euros pretending it's true high fidelity, it's an honest product. I think there are other enemies to defeat in the audio world.

Personally I want to hear the amount of pleasant distortion that the artist/producer think was right. If you want more effects go for it, just don't tell me thats more hifi. You can also add other distortions like reverb if you want. Go for it.

 

[Talisman]

Personally I want to hear the amount of pleasant distortion that the artist/producer think was right. If you want more effects go for it, just don't tell me thats more hifi. You can also add other distortions like reverb if you want. Go for it.

what's the point of asking to send one to Amir to measure it? We all know very well what we get, tons of harmonics, high distortions and 40db sinads, what do you want to prove? that a small Chinese box with two tubes won't play hi-fi? Do we need Amir's test to know that?
This is a game, a nice little box that might smooth out the sound in a small secondary or tertiary setup, presumably plugged into equally cheap little amps. I don't think anyone intends to use it between a 1000 euro dac and a purifi power amp connected to kef R7s.
So the question is, why this ferocious harassment against these cheap little products? We know what they are, we know what they do, they don't try to sell them for thousands of euros pretending it's true high fidelity, it's an honest product. I think there are other enemies to defeat in the audio world.

What are you talking about?