SET amp owners thread
- Thread starter bonzo75
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Counting cost per watt for sets is the same as counting cost per transformer weight and making OTL sound expensive. It’s a silly metric to position a design negatively
I certainly agree with that! High end is driven by intention, not weight or price
FWIW though our OTLs tend to not weigh that much, for example our M-60 amplifier is about 25 pounds which is not bad for a 60 Watt monoblock. FWIW they typically cost less than SETs that only make a quarter of the power. Even the cost of all the power tubes is less. Our OTLs are full power to 2Hz as well. Maybe using an OTL by comparison isn't the best example.
SET’s wont make bass on poorly designed speakers , with a proper match, SET’s do make bass , very good bass ..!
Bass "perception" is a topic of its own. My amp and speaker make "better" bass (rolls of at 50db) than my friends system (IMO) with excellent subs and 250 watts of AB into a ported box speaker. But he makes much more bass that is far deeper where I can clearly hear low organ notes that are only a dream with my speakers. But his bass does not have as much speed and realism. Its darn good. And I get where he's at. And I am striving to get more depth from mine. But I feel I'm at a better launch point to get excellent bass with additional work.
If a SET and horn are making fast, realistic and harmonically complete bass to say 50db, then they can be perceived by the owner to make very good bass. Especially with the mid bass/midrange bloom.
Do SET make distortion free bass to 50 hertz?
Where is the cut off where it becomes an extraordinary feat for a SET system to get to 20 hert.
If a SET and horn are making fast, realistic and harmonically complete bass to say 50db, then they can be perceived by the owner to make very good bass. Especially with the mid bass/midrange bloom.
Do SET make distortion free bass to 50 hertz?
Where is the cut off where it becomes an extraordinary feat for a SET system to get to 20 hert.
Yes if they heard the bass from my speakers they wouldn’t make such poorly thought out generalisations.
SET thread descends into Yet Another Ralph Anti SET , Atmasphere Product Placement , Shill Off … What A Shocker … Yawn !
If Ralphs' comments are factually inaccurate - then demonstrate that is the case - if not find something more interesting (for you) to read...
If I could be Bothered with you … I would Reference the list of SET orientated threads , both here and elsewhere, that He has Shat all over with His Theoretical Opinions which curiously always seem to promote His own opposing circuit topology and ergo His own product portfolio …
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Two things...
1. Ralph has owned & operated a successful amplifier company for over 30 years standing & until the last few years exclusively tube design - manufacture & sale. That demonstrates he does know what he's talking about when it comes to tube design.
2. What I find amusing is you are doing exactly what you are accusing Ralph of
I will repeat my previous comment - "If Ralphs' comments are factually inaccurate - then demonstrate that is the case - if not find something more interesting (for you) to read..."
Owing to the well-known engineering problem of an elliptical load line, this statement seems unlikely.
Your speakers go low enough you should be able to shake the room. Maybe you meant '50Hz' above. That's OK, but for anyone who plays a bass instrument its not convincing. No SET makes 'distortion free' bass at 50Hz but most can do 50Hz alright. At 20Hz, even with only 7 Watts full power at that frequency is impossible. You see the problem when you understand that most musical energy exists in the bass region.
Must've hit a nerve... You'll note I was not the one that brought up 'OTLs'. How is it that when well-known facts get stated, the messenger is the bad guy and gets personal attacks??
I learned about the elliptical load line thing from an SET advocate. Sheesh. Apparently he gets around the problem by using a crossover and powered subs.
The thing about the ear is that it has its own tone control thing built-in. If bass is lacking, the highs will seem highlighted. Too much bass and the highs will sound muffled. That is why its so important to get the bass right. Anyone here should really take this to heart if they want to hear what their SETs really do well- use subwoofers and consider getting the amp modified to roll off bass below 80 Hz or so, or get an electronic crossover to keep bass out of the amp. You'll hear this relax the amp quite a lot and detail will be easier to pick out. Since most SETs have no feedback, everything (like frequencies they have no business playing) affects them.
Yes, I can- in which case get out there and show us all how its done.
Nope … merely a touch weary of your games … It would appear that you have gone all Pavlov Dog and are merely repeating yourself !
Sounds like I was right- I did hit a nerve. It was not intended. Sorry you took it personally.
So Formulaic … So Wearisome … Does this usually work for you Ralph ?
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At the very least Ralph is wrong about SETs generating full power down to 20Hz.
The first plot (top left) is the distortion vs. Frequency at different power levels. The Lamm ML2 is rated at 18 watts and this plot shows the distortion at 20hz is essentially the same as at higher frequencies. This amp can produce 18 watts at all frequencies with the same distortion, which indicates a sufficiently large output transformer core with proper winding to allow high frequencies to be maintained. Perhaps Ralph only has experience with inferior designs, which can be compromised.
Ralph made OTLs for 30+ years, which are notoriously load intolerant and bass shy when poorly matched to the speaker. It was so much the case that there was a bit of a cottage industry around autoformers (Spletz for example) to allow them to work better with a lot of speaker types. OTLs are also notoriously low power into tougher loads unless HUGE with dozens of tubes.
The truth is that an amp without negative feedback will have LESS interaction with the loudspeaker than one with negative feedback. This was demonstrated by Matti Otala in the 80s. He found the back EMF from the driver/crossover network can wreak havoc on feedback amplifiers because the feedback creates a conduit that allows back EMF to be pumped back into the input of the amp and reamplified. No feedback means no conduit and no amplification of badly distorted signal coming back from the speaker. Most people don’t realize that the signal comes back…it’s a circuit. Without feedback on a SET that back signal just gets dissipated as heat. Same for any tube amp without feedback. For highly reactive speakers, like electrostatics, this can be so bad it can make a high feedback amp oscillate.
Now he wants to claim Class D is the second coming and basically disavows a lot of what he preached for 30 years. Like negative feedback. He used to tout his amps didn’t use any and now he slags SETs because they don’t use it.
Finally, he fundamentally doesn’t understand or deliberately misinterprets psychoacoustic findings to try to make it fit his amp topology of choice.
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And exactly how long have you been designing - manufacturing & successfully selling your own brand of tube pre amplifiers & power amplifiers...
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