I am sick of failing amplifiers
- Thread starter Kingrex
- Start date
I moved my mesh router to the guest house while some work was going on in the main house. That meant no streaming. I played a bunch of tape. And the tape is really good. But I was missing digital. So I went out to the guest house and brought it back in for the evening. I am completely satisfied with my digital. I was missing it and feel extremely relaxed and comfortable having it playing again. Maybe it's because I have been tuning my stereo for the last few months with it. It blends perfect. No i'm not playing classical. I'm playing modern music I like.
Put simply, it isn't. The analogy does not hold up.
That of course is the allure- the distortion is enjoyable. But its not accurate. SETs IMO have a lot in common with musical instruments while most other amps are more like musical reproducers.
They would of course be guilty of a logical fallacy
I've mentioned this before but if you really are stuck on SETs, if you really want the most out of one then do something to prevent bass getting into the amp- by use of a crossover or the like (perhaps lower value coupling caps). Most SETs have a cut core in the output transformer to reduce saturation distortion caused by the current of the power tube inducing a DC magnetic field in the core. The saw cut vastly reduces the DC magnetization. The problem is that this reduces the inductance of the output transformer at low frequencies. This means that as the inductance decreases with frequency, so does the load on the tube. It also introduces something called an 'elliptical load line'. The load line is a design characteristic that defines the distortion and working conditions of the tube. It should be a straight line. When it goes elliptical its hard on the tube.
This is why nearly any SET cannot make bass frequencies at full power. At lower power levels maybe they can; but the bass notes are causing the amp to make a lot of distortion. If you can prevent low frequencies from driving the load line elliptical, the amp will be much better behaved and this will translate instantly to greater transparency, greater detail, more musical, that sort of thing. The people I know who are the most ardent about SETs all do this- they acknowledge and are pragmatic about the fact that this is a real issue for SETs.
I was bouncing around the idea of multi amping my system again. To do it, i'm gonna have to use an active crossover. My blade amp would run the mid range. I was told the best way to run my horn tweeter would be a SET 45. Everything has its place. A class D amp would drive the woofers.
Not necessarily.
One can use an analogue High Pass Filter (HPF), which can be as simple as the capacitor that @Atmasphere suggested.
Then a powered subwoofer can pick that off of the speaker level, and inverse LPF.
Or a RCA/XLR level as analoge
Or RCA/XLR as active - but leave the HPF side clean and unadulterated by DSP.
Maybe best, or good.
It is certainly a better case to run a tweeter with a SET, than a woofer or full range.
But it can sometimes be best if the MR and Tweeter (and woofer) have the same distortion profile.
100%
Remember the honey mooners bang zoom ,Put simply, it isn't. The analogy does not hold up.
That of course is the allure- the distortion is enjoyable. But its not accurate. SETs IMO have a lot in common with musical instruments while most other amps are more like musical reproducers.
They would of course be guilty of a logical fallacy
I've mentioned this before but if you really are stuck on SETs, if you really want the most out of one then do something to prevent bass getting into the amp- by use of a crossover or the like (perhaps lower value coupling caps). Most SETs have a cut core in the output transformer to reduce saturation distortion caused by the current of the power tube inducing a DC magnetic field in the core. The saw cut vastly reduces the DC magnetization. The problem is that this reduces the inductance of the output transformer at low frequencies. This means that as the inductance decreases with frequency, so does the load on the tube. It also introduces something called an 'elliptical load line'. The load line is a design characteristic that defines the distortion and working conditions of the tube. It should be a straight line. When it goes elliptical its hard on the tube.
This is why nearly any SET cannot make bass frequencies at full power. At lower power levels maybe they can; but the bass notes are causing the amp to make a lot of distortion. If you can prevent low frequencies from driving the load line elliptical, the amp will be much better behaved and this will translate instantly to greater transparency, greater detail, more musical, that sort of thing. The people I know who are the most ardent about SETs all do this- they acknowledge and are pragmatic about the fact that this is a real issue for SETs.
Your theory has big meret ..
Who understands well pick bang or zoom .
If the set has ss psu this helps , but all you said has been shown if one listens
Set has color so the speaker needs to need it to sound good
Same as you say but shows practical observations. I did not know the cut is purely freq driven . I thought it was imp curve driven did not know freq driven .
a question does larger tubes that have lower mohs help Ralph ? You would know way more then I do .
Put simply, it isn't. The analogy does not hold up.
That of course is the allure- the distortion is enjoyable. But its not accurate. SETs IMO have a lot in common with musical instruments while most other amps are more like musical reproducers.
They would of course be guilty of a logical fallacy
I've mentioned this before but if you really are stuck on SETs, if you really want the most out of one then do something to prevent bass getting into the amp- by use of a crossover or the like (perhaps lower value coupling caps). Most SETs have a cut core in the output transformer to reduce saturation distortion caused by the current of the power tube inducing a DC magnetic field in the core. The saw cut vastly reduces the DC magnetization. The problem is that this reduces the inductance of the output transformer at low frequencies. This means that as the inductance decreases with frequency, so does the load on the tube. It also introduces something called an 'elliptical load line'. The load line is a design characteristic that defines the distortion and working conditions of the tube. It should be a straight line. When it goes elliptical its hard on the tube.
This is why nearly any SET cannot make bass frequencies at full power. At lower power levels maybe they can; but the bass notes are causing the amp to make a lot of distortion. If you can prevent low frequencies from driving the load line elliptical, the amp will be much better behaved and this will translate instantly to greater transparency, greater detail, more musical, that sort of thing. The people I know who are the most ardent about SETs all do this- they acknowledge and are pragmatic about the fact that this is a real issue for SETs.
Like I said, some people just aren't capable of designing great SET's that overcome the issues and some people are. It's ok if you aren't able to.
No one is the authority on what is bad or wrong - true or not true when it comes to personal tastes.
If someone likes what they hear, that's all that really matters and we should celebrate that with them in the spirit of great hifi audio, even if we have different tastes.
We should spend more time celebrating what people like and not trying to tell them they are wrong.
Ralph addressed objective points - IMO his authority comes from the facts, not just from his experience. Any one can debate them presenting objective data and his opinion.
Are you trying to create new rules in WBF? I come here to get information, read, learn and debate about high-end matters. I really enjoy reading people experiences, but not just "celebrations".
Sorry, no one was telling people they are wrong on their subjective opinions - just addressing the technical aspects behind the subjective.
Just to say that a forum like WBF should be happy and proud of having someone as Ralph Karsten posting about such matters and debating with him.
One may not like Ralph's honesty in design we are lucky to have him here . Go post on diy and see what happens lol
My thinking is an set amp is made for purpose type amp and does not fit in many ways in a variety of speakers
I use one for headphones and love there sound . But this is not a speaker where damping and imp curves play a big part
My thinking is an set amp is made for purpose type amp and does not fit in many ways in a variety of speakers
I use one for headphones and love there sound . But this is not a speaker where damping and imp curves play a big part
Do you have data?
Gawd my high school teachers would have ripped you up.
And it was a vanilla school.
There is probably someone running a subwoofer with a SET, but they’re not right.
You are welcome to be happy and proud of Ralph all you'd like.
Sounds like 'you are making new rules'.
Hi Homlz,
I think you are confused. 'Data' isn't needed on a statement that not everyone can design a perfect everything.
Have a great day!
In the spirit of my post of being happy when others are happy - I'm very happy for you that you feel so lucky.
You are welcome to be happy and proud of Ralph all you'd like.
Sounds like 'you are making new rules'.
Anyone able to read our posts will notice I clearly stated it was my opinion and forum preferences, not what others should do. Please feel free to have fun and celebrate - happy to read about it - but please do not change the sense of my posts.
The kind of power supply used isn't relevant.
The issue is in the output transformer and really has little to do with the power tube, although smaller power tubes like the type 45 are better simply because the demands on the transformer are less profound. The transformer has a winding around a series of steel plates called 'laminations'. The winding has current going through it from the power supply to the power tube. That essentially causes it to act as a magnet. When the laminations are magnetized in this manner, there's literally nothing left for the audio signal so it is distorted. This is called 'saturation'.
To avoid this a saw cut is made through the lamination in the right place, which vastly reduces the DC aspect of the magnetization. This allows the signal to pass with far less distortion. However, as the frequency goes down, the saw cut causes the winding to have less inductance at lower frequencies and so takes on more of the aspect of the DC resistance of the winding, which might be only a few hundred Ohms, while the tube needs to see a few thousand Ohms as a load! Its a bit more complex than I'm explaining right now, but in essence the load on the power tube becomes inappropriate and more so the lower the frequency. This causes a loss of power at those frequencies (an inability of the transformer to pass low frequencies) and increased distortion.
It also shortens the life of the tube due to excess heat.
The only way around this problem is a circuit called a parafeed, which use a coupling capacitor between the power tube and transformer, but such circuits have problems of their own, one of them being they are less efficient.
So the bottom line is don't put bass frequencies through an SET if you want the SET to really work properly. This problem is peculiar to SETs.
This really isn't about trying to make anyone wrong. Fact and just trying to make someone wrong are two very different things...
This is just engineering.
As always, my recommendation is if you want to know about how SETs compare to other amps, do as much as you can to level the playing field. For example use the same power tubes in both kinds of amps when doing the comparison. Or use a PP amp of the same rated power as the SET. Use the same kind of parts and power supplies and so on. I've done all these things FWIW.
There's a big difference between, i'm happy and like the sound, and something being technically correct.
Ralph does post many times explaining to people what is technically correct. Yet as many or more respond back in a way that seems to say they disagree with the electrical engineering because they like the sound they are hearing. Or that what they hear does not fit with the technical explanations Ralph gives.
I personally find Whatsbestforum to be a place to learn. To me, technical details are more important than personal perceptions. Personal perceptions matter. But understanding why somebody might or might not perceive something, is if greater value to me.
Ralph does post many times explaining to people what is technically correct. Yet as many or more respond back in a way that seems to say they disagree with the electrical engineering because they like the sound they are hearing. Or that what they hear does not fit with the technical explanations Ralph gives.
I personally find Whatsbestforum to be a place to learn. To me, technical details are more important than personal perceptions. Personal perceptions matter. But understanding why somebody might or might not perceive something, is if greater value to me.
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