Recently I posted a build on reddit.com, which is a forum for almost anything if any of you are familiar with it. However, at some point it turned from just checking out the amp to arguing about the merits of different kinds of amps. I was wondering if there is any sense to the following message?
They're rated to 1% THD at full power, so 400W RMS. THD isn't proportional to power though, it skyrockets in the last 100 watts or so as the output filter approaches saturation.
To give you an idea:
From 20Hz<f<20kHz, at half the rated power and under, typical THD will be 0.01%, max THD will be 0.05%
At 1W, from 20Hz<f<20kHz, Max THD will be 0.004%, but wait, there's more.
This performance is virtually independant of load, and frequency. THD Vs Frequency is ruler flat, and with stepped loads changes very little, arguably insignificantly, so you have a very high degree of neutrality and transparency.
It suffers a very small degree of signal compression on the highs towards saturation, which is similar to what tubes do. The only difference is that instead of compressing further once it reaches clipping, it hard clips. I avoid all that ******** by by running it at half gain and, for now, half power. On the bright side, my speakers are rated at 102dB 1w/1m, and I can run my system at 11 clip free compression free and distortion free 24/7 without it ever breaking a sweat, not so much for the neighbours though.
The nice thing about class d is that you can put this kind of power and performance into it without a large portion of the cost going into heatsinking. It's cooled by convection and conduction to the plate that it's bolted to and nothing else. If you tried that with a class A amp you'd likely have to double your total cost just in metal and it would still be ******* hot.
Once you get into the range of hundreds of watts all you are doing is buying headroom for spikes which are hardly even necessary.
BS excuses... I've heard them all. There are amps out there that **** the bed completely just from having too capacitive a set of speaker wires attached. You need power built into it to supply the reactive loads without overburdening the amp and supply, otherwise it sounds like ***.
It's kind of amusing in a way to see a guy with a tube amp argue against the need for clean dynamics.... I'll let you off this time. I say that because modern crap that passes for music is largely free of dynamics, but when you crank that **** up it sucks even more power.
You should be aware that the kind of guys from which such arguments originate are really full of it, because they sell "first watt" single transistor 10 dollar worth in parts amps for 10X that. What happens to distortion after that 1W is ******* ugly. What happens to distortion with load is ******* ugly. What happens to distortion with frequency is ******* ugly.
So they get these "first watt" amps, that can only produce reasonable THD for a very specific set of very unrealistic working conditions that it won't ever see in practice, and couple them to room sized horn loaded speakers to get some loudness out of it. They act like instruments in themselves, because "analytical is cold" and they think that has to be other extreme to "warmth" and "musical", with no accurate in between.
What you wind up then with is a system that sounds ******* amazing, if you only ever play simplistic jazz /horn recordings with no dynamics.
On the other hand, while not absolutely perfect, my system can go from Tool, to electronic, to orchestral, which btw, takes a motherload of power and accuracy, to unreal tournament, to the space shuttle blasting off, cars running laps, any movie soundstrack and special effect and sitcom laugh tracks... doesn't fukn matter it rocks them all.
But my amps are also extremely unique, especially in class d land. You would have a very difficult time discerning my amp from any class A... it would sound better in some ways and slightly worse in others. But generally class D will sound like *** even with a good design. Proper effort just doesn't go into them and most everyone lacks the knowhow both in design and all aspects of realization.
Built my first amplifier kit : Music
They're rated to 1% THD at full power, so 400W RMS. THD isn't proportional to power though, it skyrockets in the last 100 watts or so as the output filter approaches saturation.
To give you an idea:
From 20Hz<f<20kHz, at half the rated power and under, typical THD will be 0.01%, max THD will be 0.05%
At 1W, from 20Hz<f<20kHz, Max THD will be 0.004%, but wait, there's more.
This performance is virtually independant of load, and frequency. THD Vs Frequency is ruler flat, and with stepped loads changes very little, arguably insignificantly, so you have a very high degree of neutrality and transparency.
It suffers a very small degree of signal compression on the highs towards saturation, which is similar to what tubes do. The only difference is that instead of compressing further once it reaches clipping, it hard clips. I avoid all that ******** by by running it at half gain and, for now, half power. On the bright side, my speakers are rated at 102dB 1w/1m, and I can run my system at 11 clip free compression free and distortion free 24/7 without it ever breaking a sweat, not so much for the neighbours though.
The nice thing about class d is that you can put this kind of power and performance into it without a large portion of the cost going into heatsinking. It's cooled by convection and conduction to the plate that it's bolted to and nothing else. If you tried that with a class A amp you'd likely have to double your total cost just in metal and it would still be ******* hot.
Once you get into the range of hundreds of watts all you are doing is buying headroom for spikes which are hardly even necessary.
BS excuses... I've heard them all. There are amps out there that **** the bed completely just from having too capacitive a set of speaker wires attached. You need power built into it to supply the reactive loads without overburdening the amp and supply, otherwise it sounds like ***.
It's kind of amusing in a way to see a guy with a tube amp argue against the need for clean dynamics.... I'll let you off this time. I say that because modern crap that passes for music is largely free of dynamics, but when you crank that **** up it sucks even more power.
You should be aware that the kind of guys from which such arguments originate are really full of it, because they sell "first watt" single transistor 10 dollar worth in parts amps for 10X that. What happens to distortion after that 1W is ******* ugly. What happens to distortion with load is ******* ugly. What happens to distortion with frequency is ******* ugly.
So they get these "first watt" amps, that can only produce reasonable THD for a very specific set of very unrealistic working conditions that it won't ever see in practice, and couple them to room sized horn loaded speakers to get some loudness out of it. They act like instruments in themselves, because "analytical is cold" and they think that has to be other extreme to "warmth" and "musical", with no accurate in between.
What you wind up then with is a system that sounds ******* amazing, if you only ever play simplistic jazz /horn recordings with no dynamics.
On the other hand, while not absolutely perfect, my system can go from Tool, to electronic, to orchestral, which btw, takes a motherload of power and accuracy, to unreal tournament, to the space shuttle blasting off, cars running laps, any movie soundstrack and special effect and sitcom laugh tracks... doesn't fukn matter it rocks them all.
But my amps are also extremely unique, especially in class d land. You would have a very difficult time discerning my amp from any class A... it would sound better in some ways and slightly worse in others. But generally class D will sound like *** even with a good design. Proper effort just doesn't go into them and most everyone lacks the knowhow both in design and all aspects of realization.
Built my first amplifier kit : Music
Don't sweat it.
I was a solid state user, Hifi AND guitar. - It's a generation thing.
I am over 18 months clean.
About the only things tubes to good, is play music.
I can hear it, I can hear what others are talking about. I felt what other guitarists felt.
I would take the slightly higher distortion any day of the week.
I don't know much about class-D amps, and yes there are some nice SS amps out there, but they are few and far between and need to be designed well.
Most tube amps sound good.
Most SS amps are lacking.
Even an idiot like me can build a tube amp that sounds better then anything I can buy at Futureshop, so what does that tell ya.
I was a solid state user, Hifi AND guitar. - It's a generation thing.
I am over 18 months clean.
About the only things tubes to good, is play music.
I can hear it, I can hear what others are talking about. I felt what other guitarists felt.
I would take the slightly higher distortion any day of the week.
I don't know much about class-D amps, and yes there are some nice SS amps out there, but they are few and far between and need to be designed well.
Most tube amps sound good.
Most SS amps are lacking.
Even an idiot like me can build a tube amp that sounds better then anything I can buy at Futureshop, so what does that tell ya.
The guy in the reddit thread claims he needs hundreds of watts. He might with the right or even wrong set of speakers. His argument with the First Watt amps is the same against tubes. Don't forget that everyone you meet on the internet is an expert in everything along with being an internet tough guy.
He's happy with a few hundred watts and I'm happy with 10. Who is right?
He's happy with a few hundred watts and I'm happy with 10. Who is right?
Never heard of reddit.com before. My wife calls it a social bookmarking site. Not exactly a place to learn about amplifier design, or the differences between them. Some of the posts below yours are kinda scary.
BTW, tubes are worth every penny, especially the cheap ones.
jeff
So he's basically said that class D saves on heatsinking vs class A, which is true enough. He's also saying it's nicely linear throughout its usable range.
Also mentions the lack of dynamics available from low-powered designs. Fair enough - clean headroom is needed to get a large dynamic range. He also points out there's diminishing returns past a couple of hundred watts. This figure will, of course, depend on how loud you like it, listening conditions, speaker sensitivity, etc.
Then he goes on to say that his system is one of the best in the world, being able to play anything you like, loud as you like. He obviously likes it, and thats all he needs in the end.
If it wasn't for all the expletives, I wouldn't mind posts like this so much.
Chris
Also mentions the lack of dynamics available from low-powered designs. Fair enough - clean headroom is needed to get a large dynamic range. He also points out there's diminishing returns past a couple of hundred watts. This figure will, of course, depend on how loud you like it, listening conditions, speaker sensitivity, etc.
Then he goes on to say that his system is one of the best in the world, being able to play anything you like, loud as you like. He obviously likes it, and thats all he needs in the end.
If it wasn't for all the expletives, I wouldn't mind posts like this so much.
Chris
Some of the best solid state designs I've heard are the ones that take advantage of tricks to make up for the problems that SS has. For example, my home theater reciever sounds pretty nice because it takes a digital signal, has nice DACs right next store to the discrete chips that amplify the signal and there is all kinds of EQ stuff to play with that modifies the signal in the digital domain. The trick is to use a good signal, HDMI audio supports some very high resolution sources. I wish people cared more about that be no one says a word and we are stuck with music CDs. You can spend billions of dollars making your CD's sound good but it's still a CD.
I think if you were to take the amp section out of the reciever and just have rca plugs on it no one would be interested.
I have heard some really nice sounding SS amps for the record. One was some kind of ebay tripath board that ran directly off an SLA battery. Really suprised me. Kinda high maintenance though.
I have head some super expensive solid state stuff that was just good but not great. Heaps of power of course. That guy was right about orchestral music needing a lot of power. That's why I like solid state, POWER.
Anyone have an active crossover system with tubes above 200hz and SS below that to a woofer? Maybe that would be the best of both worlds.
BTW, you guys who build your own amps are cool! One day I will get into that but I don't feel up to it just yet.
I think if you were to take the amp section out of the reciever and just have rca plugs on it no one would be interested.
I have heard some really nice sounding SS amps for the record. One was some kind of ebay tripath board that ran directly off an SLA battery. Really suprised me. Kinda high maintenance though.
I have head some super expensive solid state stuff that was just good but not great. Heaps of power of course. That guy was right about orchestral music needing a lot of power. That's why I like solid state, POWER.
Anyone have an active crossover system with tubes above 200hz and SS below that to a woofer? Maybe that would be the best of both worlds.
BTW, you guys who build your own amps are cool! One day I will get into that but I don't feel up to it just yet.
Are tubes worth it... NO!!
Leave them alone don't listen to the mermaid singing
You will be spoilt for life...Then again until you try the all the sweets in the shop how do you know what’s best...
Sugar and spice....that’s what tubes are made of...
LMAO to err is to human to be indecisive that’s women isn't it?
Blonde/ brunette /red/ <<< no decision I'll take all thank's..LOL
Regards
M. Gregg
Leave them alone don't listen to the mermaid singing
You will be spoilt for life...Then again until you try the all the sweets in the shop how do you know what’s best...
Sugar and spice....that’s what tubes are made of...
LMAO to err is to human to be indecisive that’s women isn't it?
Blonde/ brunette /red/ <<< no decision I'll take all thank's..LOL
Regards
M. Gregg
I donno M.Gregg... It's taken me since the mid 60's to find tube nirvanna. The BAT VK-60 comes very very close. So far no OTL has accomplished it including those from Fourier and Atmosphere. None of the three or four from Audio Research that have passed through, none of the solid state amps that have lived here even come close... I recently however stumbled across it in the form of a 30 wpc $320.00 Chineese amp using a pair of 829B transmitter finals. Toss those included Chineese tubes right in the trash and for reliabilitie's sake reach for a pair of JAN RCA 829's teamed up with matched pairs of Russian 6N1 & 6N3 input and drivers. Utterly amazing!!! This amp now rests atop my stack of amps... An Aleph 30 and a KSA-50... both highly regarded amps in their own right, one of them on Stereophiles 10 best amps of all time list. This Chineese amp thrashes them all!
Mark
Mark
Hey.... What about apartment dwellers who can't reproduce orchestral dynamics in their homes without threat of eviction? For us, it's the reproduction of detail, timbre, acoustic space, etc. that seals the deal.
In my (limited) experience, it's been so much easier and cheaper to get this so-called "musicality" from low power tube amps than from even very expensive solid-state amps. Also, there's that harshness in the sound of so many solid-state amps, even expensive ones.
If you have your own big house, lots of acres around you, and a good solid foundation with good acoustics, then yeah, get that 400 watter so you can drive giant, power-hungry audiophile-approved megaspeakers to 115dB peaks. Even better, build your own dedicated listening studio, with proper acoustical treatments.
In the real world as it is for many of us, there's something really nice about a good tube amp.
--
In my (limited) experience, it's been so much easier and cheaper to get this so-called "musicality" from low power tube amps than from even very expensive solid-state amps. Also, there's that harshness in the sound of so many solid-state amps, even expensive ones.
If you have your own big house, lots of acres around you, and a good solid foundation with good acoustics, then yeah, get that 400 watter so you can drive giant, power-hungry audiophile-approved megaspeakers to 115dB peaks. Even better, build your own dedicated listening studio, with proper acoustical treatments.
In the real world as it is for many of us, there's something really nice about a good tube amp.
--
What is your proof is that a low-powered tube amplifier can reproduce the 100dB dynamics better than a solid-state one?
You have a given low-level sensivity of the ear, add 100dB to that and you will get the maximum level needed. There is no way around it. Tubes won't make you hear better.
Ah, their glow might make some people BELIEVE that they hear better? Sure...
Some people like the distortions induced by tubes and call them "warmth". Sure...
I prefer to hear the music as close to reality as possible.
You have a given low-level sensivity of the ear, add 100dB to that and you will get the maximum level needed. There is no way around it. Tubes won't make you hear better.
Ah, their glow might make some people BELIEVE that they hear better? Sure...
Some people like the distortions induced by tubes and call them "warmth". Sure...
I prefer to hear the music as close to reality as possible.
If I'm honest I do like counterpoint, Krell, and magneplanar...
Then again I do like OTL...I'm not a fan of Ongaku<<<thought I would be until hearing it at a HIFI convention.. Then again many do!!
The problem with sound is you get used to it and then it dosen't push the buttons so well..
Also we cannot have a different system every time we play a different style music..<<this is a problem...For me OTL has no " style limitation".YMMV
I play many different types of music..I guess you are the same..
Isn't it a pain when you try hard to get the "right" sound and go to a friends who has been to the second hand shop and it blows yours away!
Regards
M. Gregg
An interesting comment...How do you know it is close to reality...
If you are in a concert with 1000W PA and a hall....how can it be close to reality?
Don't get me wrong I know what you are saying...horses for courses...We are all after reality...however its all going to be a preference of sound. Create a disco in your house will it be the same as the disco from the club last night...maybe their amps were not what you have...
Regards
M. Gregg
It isn't a "generation thing"; it's a marketing dept. thing. All those slick audio mags aren't gonna be doing write-ups of fifty y/o equipment. That would P.O. the advertisers, pointing out that their new stuff didn't sound as good as the old stuff. There is no $$$$ to be made from advertising "old stuff". If nobody tells you about the "old stuff", then how do you know?
It's cheaper to do a marketing campaign about the sonic "glories" of that "cool" new MOSFET sound than admit the truth: MOSFETs don't work right when substituted into those SEPP topologies originally designed for power BJTs. Get 'em to believe that the resulting distortion is a "cool new sound", and you'll have 'em eating out of your hand.
Not true. Tubes are also a significant improvement when it comes to SW radio. A good ol' fashioned LC oscillator (especially if it includes an air coil and a good quality, double bearing, air variable tuning capacitor with brass plates) can be driven hard enough render phase noise virtually undetectable, and the VT itself has the self regulation to eliminate amplitude noise. (BJT based oscillators require an external servo for this.) Phase noise becomes problematic when using XTAL controlled oscillators: more drive makes for more heat in the XTAL (which is a very poor thermal conductor) and more frequency drift. Less drive means less drift, but greater phase noise. For that reason, oven warmed XTALs were often used to get the drive, and to keep down the frequency drift..
A cleaner LO makes for a more sensitive receiver. Also, a cleaner master oscillator makes you a much better neighbor on the transmit side. It may seem to be NBD if your max legal ham xmtr puts out a microwatt of extra noise (and a lot of them -- even commercial rigs -- put out a lot more than that). Since even an average receiver is sensitive down to 10^-15W, that will raise the noise floor across an entire ham band for miles around the antenna.
Solid state oscillators and frequency synthesizers that are PLL-based are significantly more noisy than any simple LC VT oscillator. They are easier to tune, and one PLL can replace whole racks of crystals for fixed frequency services like CB or aviation. The output won't be as clean, so there's your trade-off.
BJT-based basic oscillators also suffer from parametric phase distortion that you don't get with VTs, and so the output of just about any transistor oscillator needs buffering and bandpass filtering that you often don't require with hollow state oscillators.
There is no reason for SS to sound as bad as it does. I've designed both: hollow state and solid state. Getting a decent-sounding SS rig requires a good deal more effort, and probably lots of horrible-sounding PCBs hitting the trash, but it is do-able. In the end, it comes down to the same thing: use your own judgement, and don't simply copy something because audiophool folk "wisdom" says something's "better". Chances are it really isn't.
A lot of tube amps are also lacking. John Q. Public doesn't know good sound when he hears it because he never has. If there's no obvious distortion, then he's happy. There are a lot of tube amp designs where considerable sonic compromises were made to get cost of production down. Some are as hideous as SS.
As for SS amp design, you can get through an entire course of EE without once ever seeing anything about distortion in audio amps and what to do about it. As a result, most of your production SS designs were done by folks who quite literally don't know what they're doing. You can see it in published schemos, and you sure can hear it at home.
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