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Tube (valve) amplifier question

Started by Unknown June 15, 2015
I have decided to build myself a little tube amplifier so I can hear
one and compare it to my modern solid state stuff.  Virtually all the
kits and designs I see online are low wattage output compared to the
solid state stuff. I read that part of the reason for this is because
a tube amp at maximum output distorts the sound in a way that most
folks find agreeable whereas transistor amps distort in a way that
most folks don't like at all. So the transistor amps are used well
below their maximum output while tube amps can be used all the way to
full output. Is this true? See this link:
http://www.s5electronics.com/gstereo.html
This amp is an example of what I would like to build but 8 watts seems
like I wouldn't be able to really blast the music, which I sometimes
like to do.  I will be using the amp in my machine shop which
currently is provided with sound by a Pioneer SX-434, which according
to the manual puts out 15 watts per channel. So I would really
appreciate some advice from the folks here about tube amps.
Thanks,
Eric

On Mon, 15 Jun 2015 09:00:20 -0700, etpm@whidbey.com wrote:

>I have decided to build myself a little tube amplifier so I can hear >one and compare it to my modern solid state stuff. Virtually all the >kits and designs I see online are low wattage output compared to the >solid state stuff. I read that part of the reason for this is because >a tube amp at maximum output distorts the sound in a way that most >folks find agreeable whereas transistor amps distort in a way that >most folks don't like at all. So the transistor amps are used well >below their maximum output while tube amps can be used all the way to >full output. Is this true?
No. It's just a lot easier to build a high power transistor amp than it is to make a high power tube amp. That's because transistors and mosfets mount on heat sinks, and tubes don't. Not to mention the cost of a high power, 20-20KHz output transformer. See this link:
>http://www.s5electronics.com/gstereo.html
I bet that can't do full power at 20 Hz, with those dinky transformers. The tubes will eventually roast the FR4 pc board, too. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
On Monday, June 15, 2015 at 11:54:27 AM UTC-4, et...@whidbey.com wrote:
> I have decided to build myself a little tube amplifier so I can hear > one and compare it to my modern solid state stuff. Virtually all the > kits and designs I see online are low wattage output compared to the > solid state stuff. I read that part of the reason for this is because > a tube amp at maximum output distorts the sound in a way that most > folks find agreeable whereas transistor amps distort in a way that > most folks don't like at all. So the transistor amps are used well > below their maximum output while tube amps can be used all the way to > full output. Is this true? See this link: > http://www.s5electronics.com/gstereo.html > This amp is an example of what I would like to build but 8 watts seems > like I wouldn't be able to really blast the music, which I sometimes > like to do. I will be using the amp in my machine shop which > currently is provided with sound by a Pioneer SX-434, which according > to the manual puts out 15 watts per channel. So I would really > appreciate some advice from the folks here about tube amps. > Thanks, > Eric
Knowing next to nothing about tube amps, I think they are class A, which is wasteful of power. Perhaps you can find an Audiophile nearby and go listen to his. (And spend your electronic energy on something more useful.) George H.
On Mon, 15 Jun 2015 11:18:01 -0700 (PDT), George Herold
<gherold@teachspin.com> wrote:

>On Monday, June 15, 2015 at 11:54:27 AM UTC-4, et...@whidbey.com wrote: >> I have decided to build myself a little tube amplifier so I can hear >> one and compare it to my modern solid state stuff. Virtually all the >> kits and designs I see online are low wattage output compared to the >> solid state stuff. I read that part of the reason for this is because >> a tube amp at maximum output distorts the sound in a way that most >> folks find agreeable whereas transistor amps distort in a way that >> most folks don't like at all. So the transistor amps are used well >> below their maximum output while tube amps can be used all the way to >> full output. Is this true? See this link: >> http://www.s5electronics.com/gstereo.html >> This amp is an example of what I would like to build but 8 watts seems >> like I wouldn't be able to really blast the music, which I sometimes >> like to do. I will be using the amp in my machine shop which >> currently is provided with sound by a Pioneer SX-434, which according >> to the manual puts out 15 watts per channel. So I would really >> appreciate some advice from the folks here about tube amps. >> Thanks, >> Eric > >Knowing next to nothing about tube amps, I think they are class A, >which is wasteful of power.
Some are push-pull AB. They need feedback to avoid crossover distortion, and purists don't like (more like don't understand) feedback. Class A does fry tubes and limit available power. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
On Mon, 15 Jun 2015 09:00:20 -0700, etpm wrote:

> I have decided to build myself a little tube amplifier so I can hear one > and compare it to my modern solid state stuff. Virtually all the kits > and designs I see online are low wattage output compared to the solid > state stuff. I read that part of the reason for this is because a tube > amp at maximum output distorts the sound in a way that most folks find > agreeable whereas transistor amps distort in a way that most folks don't > like at all. So the transistor amps are used well below their maximum > output while tube amps can be used all the way to full output. Is this > true? See this link: http://www.s5electronics.com/gstereo.html This amp > is an example of what I would like to build but 8 watts seems like I > wouldn't be able to really blast the music, which I sometimes like to > do. I will be using the amp in my machine shop which currently is > provided with sound by a Pioneer SX-434, which according to the manual > puts out 15 watts per channel. So I would really appreciate some advice > from the folks here about tube amps. > Thanks, > Eric
Uhhhhh -- The bit about distortion is definitely true for guitar amps, more questionable for listening amps. There's a whole lot of verbiage on the subject floating around on the net. Most kits are for low-power amps because high-power output transformers for tube amps are _spendy_. Power supply transformers (if you go old school) aren't very far behind. Most of your BOM cost will go into transformers, and that cost roughly scales with power. Personally, I think the only reason to use tubes in an audio chain is for retro-cool. Some people feel that a tube preamp in an otherwise solid- state amplification chain gives better tone to the music (they also obviously feel it sells amps -- if an amp has vacuum-state preamps they will very likely be visible from the front panel). People who feel that stereo amps are best done with vacuum tubes also tend to believe that the sound will be enhanced by dipping the power cord in liquid nitrogen, which makes me skeptical about their enthusiasm. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com
Tim Wescott prodded the keyboard with:

> On Mon, 15 Jun 2015 09:00:20 -0700, etpm wrote: > >> I have decided to build myself a little tube amplifier so I can >> hear one >> and compare it to my modern solid state stuff. Virtually all the >> kits and designs I see online are low wattage output compared to >> the solid state stuff. I read that part of the reason for this is >> because a tube amp at maximum output distorts the sound in a way >> that most folks find agreeable whereas transistor amps distort in a >> way that most folks don't like at all. So the transistor amps are >> used well below their maximum output while tube amps can be used >> all the way to full output. Is this true? See this link: >> http://www.s5electronics.com/gstereo.html This amp is an example of >> what I would like to build but 8 watts seems like I wouldn't be >> able to really blast the music, which I sometimes like to >> do. I will be using the amp in my machine shop which currently is >> provided with sound by a Pioneer SX-434, which according to the >> manual puts out 15 watts per channel. So I would really appreciate >> some advice from the folks here about tube amps. >> Thanks, >> Eric > > Uhhhhh -- > > The bit about distortion is definitely true for guitar amps, more > questionable for listening amps. There's a whole lot of verbiage on > the subject floating around on the net. > > Most kits are for low-power amps because high-power output > transformers > for tube amps are _spendy_. Power supply transformers (if you go > old > school) aren't very far behind. Most of your BOM cost will go into > transformers, and that cost roughly scales with power. > > Personally, I think the only reason to use tubes in an audio chain > is for > retro-cool. Some people feel that a tube preamp in an otherwise > solid- state amplification chain gives better tone to the music > (they also obviously feel it sells amps -- if an amp has > vacuum-state preamps they will very likely be visible from the front > panel). > > People who feel that stereo amps are best done with vacuum tubes > also tend to believe that the sound will be enhanced by dipping the > power cord in liquid nitrogen, which makes me skeptical about their > enthusiasm. >
He needs an old "Trix" cinema amp to play with :-) -- Best Regards: Baron.
On Mon, 15 Jun 2015 14:23:16 -0500, Tim Wescott
<seemywebsite@myfooter.really> wrote:

[snip]
> >People who feel that stereo amps are best done with vacuum tubes also >tend to believe that the sound will be enhanced by dipping the power cord >in liquid nitrogen, which makes me skeptical about their enthusiasm.
No! You must dip the cord in red wine >:-} ...Jim Thompson -- | James E.Thompson | mens | | Analog Innovations | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | San Tan Valley, AZ 85142 Skype: skypeanalog | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food.
Get a membership at Audiokarma. A whole bunch of people there with these thoughts. there is a section devoted to tube audio. 

See you there, you'll recognize me.
et...@whidbey.com wrote:

> I have decided to build myself a little tube amplifier so I can hear > one and compare it to my modern solid state stuff. Virtually all the > kits and designs I see online are low wattage output compared to the > solid state stuff. I read that part of the reason for this is because > a tube amp at maximum output distorts the sound in a way that most > folks find agreeable whereas transistor amps distort in a way that > most folks don't like at all.
** That is mostly a myth. Firstly, no hi-fi amp should ever be driven deliberately into clipping as this defeats the whole idea of hi-fi. Secondly, occasional clipping of signal peaks ( a few times per second for example) is inaudible with both tube and SS amps. So the transistor amps are used well
> below their maximum output while tube amps can be used all the way to > full output. Is this true?
** No.
> This amp is an example of what I would like to build but 8 watts seems > like I wouldn't be able to really blast the music, which I sometimes > like to do. I will be using the amp in my machine shop
** You for real ? Hi-fi sound in a machine shop ?? .... Phil