6L6 Tube Amps sell like Gold on Ebay

[gary350]

I have noticed the old 6L6 tube amps sell like gold on Ebay.

A mono push pull amp will sell for about $100 or more and stero push pull amps for $200 to $400. WOW.......with is the deal with that???

**broken link removed**

A mono 6AQ5 push pull amp will sell for close to $100. and a stero push pull for over to $200.

**broken link removed**

Here is an old Dynaco amp they were really popular stero amps in their day.**broken link removed**


What is the deal are these collectors items?

 

[Sceadwian]

People want them... People pay for what they want, it's that simple.

 

[ke5frf]

You asked an audiophile related question but....

I am an amateur radio operator. Amateur radio is one of the most diverse hobbies you may ever dabble in. You have "hams" dabbling in Morse Code, satellite communication, digital techniques...some prefer AM, some prefer sideband, some FM...some HF, some microwaves...voice, amateur television, RTTY, homebrewing, antenna design, contests, Field Day, ragchewing...and on and on.

Point being, one of the most popular aspects of ham radio is "boat anchor collecting". While I'm not big on it, I do own a hybrid solid state-tube final Kenwood rig that is considered a boat anchor collectible. There are many old Drake, Heathkit, Hallicrafters, Collins, Hamarlund, Johnson, Swan, Lafayette, etc etc etc. Tube Type ham radios that are quite sought after and valuable in the amateur market. Many reasons for this:

Primary) Nostalgia. Ham radio boomed in the 50's and 60's and many older hams seek these tube radios because they coveted them when they were kids but had to settle for "beginner" radios. Also, many of the "beginner" radios of the past are quite popular because they were the "first rig" they ever owned and add nostalgia to the radio shack. An aside to this point: Some of these old radios are a pure joy to operate. In AM mode in particular, there is a warmth not only to the glow of the tube, but also the audible quality of the signal. Solid State amplifiers, oscillators have a different sound than tubes. Some find the tube quality better. This isn't all that different from musicians prefering tube amplifiers.

Secondary) Durability. Ease of maintenance. There is a reason these old radios are still around. Tubes can take a lot of abuse. They suffer a lot of drawbacks like instability/drift/etc and require high voltage supplies to operate but they will last a long time without degrading performance. They'll also take reflected waves for longer periods where solid state rigs will smoke. When a tube does go, it is a relatively simple repair with spare tubes on hand.

Lastly) Simple rarity of antiques. Old things that are in limited supply but are in relatively high demand will draw a handsome sum. Many collectors are in it for the profit. Buy old rigs from estate sales, ham fests, garage sales and flea markets..refurbish them (another hobbyist aspect is restoration) and sell them for a profit. And in so doing, often the boat anchor seeker will find a "jewel" for his personal collection. More often than not, the active buying, restoring, and selling of old radios pays for the man's hobby i.e. no expenses out of pocket.

Therefore, I am going to say that the audiophile "boat anchor" hobby isn't much different than amateur radio, and for many of the same reasons.

 

[Miles Prower]

What is the deal are these collectors items?

They sound better. Even a run-of-the-mill, 1950s, hollow state amp simply sounds better than the vast majority of solid state, Big Box offerings. I've designed a few SS amps that come close, but still don't quite get there, compared to hollow state. Still, way better than Big Box systems. There really is no excuse for why most commercial amps sound as bad as they do.

 

[Sceadwian]

I never quiet understood the appeal of tubes, though for some I guess the nostalgia is worth it. An EQ can make any solid state amp have distortion like a tube amp if you want it to, I don't think it ever quiet matches the exact form of distortion a tube causes to an audio signal which is why many musicians still prefer tube amps. I even saw a special edition motherboard a few years ago that.. I kid you not, had tubes for the final output stage of it's audio processor.

Images for Reviews: AOpen AX4B 533 Tube Motherboard Review

Not sure if you can still find em. Seemed really silly to me.

 

[Miles Prower]

I never quiet understood the appeal of tubes, though for some I guess the nostalgia is worth it.

Nostalgia ain't got nuttin' to do with it. Hollow state amps simply sound better since you're starting with a device that's much more linear than any transistor. Better linearity, better sonics. Huge amounts of gNFB to force a very nonlinear device into linearity just doesn't cut it. There's always something missing when you do that.

 

[Mikebits]

Nostalgia ain't got nuttin' to do with it. Hollow state amps simply sound better since you're starting with a device that's much more linear than any transistor. Better linearity, better sonics. Huge amounts of gNFB to force a very nonlinear device into linearity just doesn't cut it. There's always something missing when you do that.

I think the attraction to tube amps is the non-linear response as opposed to being linear which would defeat the purpose as semiconductor devices are very linear. I think you got things backwards. I too have compared sounds and for some reason I think a tube amp does have a unique sound that digital electronics as failed to reproduce.

 

[Miles Prower]

I think the attraction to tube amps is the non-linear response as opposed to being linear which would defeat the purpose as semiconductor devices are very linear. I think you got things backwards. I too have compared sounds and for some reason I think a tube amp does have a unique sound that digital electronics as failed to reproduce.

Sceadwian there in #5 didn't help since he was comparing two different things: sound reproduction amps and instrument amps. For the former, you don't want distortion, and for the latter, distortion is a big part of the appeal: "Marshall sound" or "Fender sound" is mainly distortion.

As for the idea that "semiconductor devices are very linear", that's just plain nuts. Audioguru once put up a post here about some new circuit (It involved a diode, splitting the emitter resistor into two equal halves, and using a couple of large capacitors to route the AC backwards through that diode. Its inventor was talking patent and was so pleased with himself since it got the THD down to 5%. By hollow state standards, that's hideous.) As for your "very linear" solid state devices, these are plenty hard to come by, and are not cheap. These SiC JFETs are effectively unobtanium unless you're prepared to order several hundred devices that go for $60.00 a pop. If you got ahold of some, you'd see that these have to run at high voltages (300V at least) to keep the internal capacitances reasonably linear, otherwise they'd be worse than any run-of-the-mill transistor.

Or you could try **broken link removed**, again, big BUX for a device that can handle a thousand watts or more in pulsed operation. Lovely transfer characteristics, but there are none of these designed for audio. SUX, but these days SS device development is geared to switching and pulsed operation, not linear applications. You'd best stock up on those lateral MOSFETs now while you can still get them (and then only from small boutique manufacturers).

"I too have compared sounds and for some reason I think a tube amp does have a unique sound that digital electronics as failed to reproduce".

Are you discussing instrument amps again? That would definitely apply. As for reproduction amps, the "unique sound" of a hollow state amp is simply that you can finally actually hear what you're trying to listen to. I had a Big Box, solid state amp, that I thought was pretty damn good, and which got some excellent reviews. Once I had my first hollow state design up and running, it was like getting a whole new CD collection for free. There was so much new detail that simply went unheard from that SS amp. Big Box solid state amps are plumbing new depths of sonic suckitude simply because most people out there have never heard good sound, and don't know what it sounds like. New recording techniques aren't helping matters either.

No reason SS has to sound as bad as it does. I've designed a few that sound really good, but that means going those extra miles that the pencil-pushers won't authorize.

 

[Sceadwian]

Miles could you use terminology that makes sense to someone from an electronics perspective? I don't even know what a hollow state amp is.

Two things I know. Tube amplifiers produce distortion from the originating signal which imparts all those 'feelings' that people seem to love to associate with high fidelity audio, which means they're non-linear. Modern solid state amps that use any kind of decent feedback will produce audio with absolutely phase perfect quality, the human ear should NEVER come into play as far as audio production goes, if someone prefers a particular 'feeling' to their music that's what EQ's are for as the non-linearity of a tube amp can be easily monitored compared to the input signal and a solid state amp could easily be tuned to match those characteristics.

High fidelty and 'good sounding' are VERY different things. A perfectly re-produced sine or square wave will drive a human being nearly insane after any length of time. The 'warm' characteristics that a tube lends to it's originating signal is in fact distortion it is however by some considered pleasing.

The onus is on the artist to make use of audio manipulation methods to produce the sounds that we find pleasing, and many modern songs are very seriously designed to sound incredibly bad by acoustical measures.

 

[ke5frf]

"Miles could you use terminology that makes sense to someone from an electronics perspective? I don't even know what a hollow state amp is."

Scaed, I assume you are familiar with the term "solid state", yes? This term was coined for a reason, i.e it is the parallel of hollow state... And both terms are most certainly used in the electronics biz.

 

[Mr RB]

They strip them for parts. A basic pushpull 6L6 amp has 2 6L6, a nice 50W or 60W output transformer, PSU transformer, pre amp tubes, tube sockets, high voltage parts. The output transformer alone can sell for $100 new.

I'm not a bit surprised that a 6L6 mono amp would sell for $100.

 

[mneary]

Vacuum tube? Output transformer? Linear????

Never saw one.

 

[Roff]

There was so much new detail that simply went unheard from that SS amp.

Yeah, it's cool how a hollow state amp can create pleasing detail that didn't exist in the original material.
THD measurements of both amps would be much more convincing, IMHO.

 

[caster.cp]

Yeah, it's cool how a hollow state amp can create pleasing detail that didn't exist in the original material.
THD measurements of both amps would be much more convincing, IMHO.

Agreed.

Tubes suck hard. It's a huge bottle, operating at huge temperatures and voltages, that adds LOTS of distortion (well designed SS amps don't sound bad, they sound RIGHT, that's the difference). Tubes are a REALLY old technology, I can't understand how a reasonably educated engineer, that knows the least of spectrum analysis, can say that tube amps are better.
This fuzz (pun intended) around tube amps were created by musicians that didn't know the first thing about electronics in the seventies.

I can understand, however, that people like the sound of tube amps, mainly because of the distortion they add to the signal.

Two things I know. Tube amplifiers produce distortion from the originating signal which imparts all those 'feelings' that people seem to love to associate with high fidelity audio, which means they're non-linear. Modern solid state amps that use any kind of decent feedback will produce audio with absolutely phase perfect quality, the human ear should NEVER come into play as far as audio production goes, if someone prefers a particular 'feeling' to their music that's what EQ's are for as the non-linearity of a tube amp can be easily monitored compared to the input signal and a solid state amp could easily be tuned to match those characteristics.

High fidelty and 'good sounding' are VERY different things. A perfectly re-produced sine or square wave will drive a human being nearly insane after any length of time. The 'warm' characteristics that a tube lends to it's originating signal is in fact distortion it is however by some considered pleasing.

I COMPLETELY agree with Scewadwin.
It makes me mad how people mix Hi-Fi with "ah, I find this better sounding...".

EDIT:

Nostalgia ain't got nuttin' to do with it. Hollow state amps simply sound better since you're starting with a device that's much more linear than any transistor. Better linearity, better sonics. Huge amounts of gNFB to force a very nonlinear device into linearity just doesn't cut it. There's always something missing when you do that.

I wonder why they don't use tubes at biomedical stuff, at avionics and military stuff. Beats me, then.

 

[Miles Prower]

Those who think they know everything really annoy those of us who do

"Tubes suck hard". Only if you break the vacuum seal, and then only for a little while.

"It's a huge bottle, operating at huge temperatures and voltages..."

And transistors require huge heatsinks and operate at huge temperatures and currents. So far, no one has figured out how to repeal P= IV. Sowatscherpoint?

"well designed SS amps don't sound bad, they sound RIGHT, that's the difference" Vocals that fade into the background to the point lyrics become difficult to understand, not even a hint of soundstage, passages that become all but inaudible -- yeah, that "sounds" RIGHT. **broken link removed**

"I can't understand how a reasonably educated engineer, that knows the least of spectrum analysis, can say that tube amps are better".

I can't understand how some newbie on some newbie message board with forums like "Homework Help", and topics like "How do I run my calculator from a car battery", "How do I make these LEDs flash", etc. can say that a professional engineer with 30 years of experience doesn't know what he's talking about.

"Tubes are a REALLY old technology..."

So are:

* Radio

* The internal combustion engine

* Automobiles

* Aviation

All older than vacuum tubes. Sowatscherpoint?

"This fuzz (pun intended) around tube amps were created by musicians that didn't know the first thing about electronics in the seventies"

What do professional musicians and sound technicians know about music? **broken link removed**

"I COMPLETELY agree with Scewadwin". Of course you do. Something about the blind leading the blind comes to mind here.

"It makes me mad how people mix Hi-Fi with 'ah, I find this better sounding...'". Damn those people who actually judge sound equipment by how it actually, you know, sounds! How dare they!

"I wonder why they don't use tubes at biomedical stuff (ah, yes, that professional IEEE, electronic engineering terminology: stuff **broken link removed** ) at avionics and military stuff. Beats me, then"

So you play your CDs through biomedical "stuff", avionics, and military "stuff"? Do tell.

Believe whatever the hell you like, keep parroting the marketing buzz from the Big Box manufacturers. God forbid you actually try to think for yourselves. I'm done with this thread and all the nonsense therein. Ciao, sheeple.

 

[Sceadwian]

ke5, I've never heard the term hollow state used before. I've heard solid state amps called hollow sounding before but that has absolutely nothing whatsoever to do with electronics, just human perception in audiophile circles. To say 'hollowstate' is an electronics term is simply wrong, you'll never find it in a text book, and the electronics 'buisness' is not what I was referring to, there's so much wrong with the buisness that surrounds audio/visual electronics as to cause me more than a little pain every time I go shopping. I see people in line buying 4 foot monster HDMI gold plated low oxygen cables for upwards of 75 dollars. I bought a 6 foot HDMI cable with gold plated connectors for 15 dollars a few weeks ago... And the picture is the same. It's horribly wrong.

caster the thing is a tube amp really CAN sound very pleasing, the distortion characteristics it adds to AM radio and voice is an audio joy to behold =) My ears like it, but I also like the pure absolute reconstruction of a solid state amp better for high fidelity audio, especially concert music. It allows you to pick artists that actually knew what they were doing when they made the songs in the first place =\ Not just throwing trash catchy tunes out there.

I'll probably be burned at the stake for saying this but I find a lot of very intense and complicated audio effects in Nine Inch Nails albums, especially the earlier stuff. But only when played back from a CD through a decent headphone amplifier. The real joy in listening to the songs is destroyed when it's listend too even in a low echo room with a good quality stereo. But a lot of NIN stuff has some pretty complex stereo phasing effects and a pretty dramatic dynamic range.

Miles you need to grow some thicker skin. The blind aren't leading the blind here there's just obviously personal opinion and feeling behind the science of the electronics involved.

Simple facts.
Solid state amplifiers are multiple orders of magnitudes better at REPRODUCING audio.
Tube amplifiers, especially well made ones tend to add distortion to some types of audio that are emotionally pleasing to a listener.
The media in question played back on either device is more important.

Miles, it's absolutely pure idiocy to say that solid state amps are worse because audio played back on them sounds different than on a tube amp, if you want to blame anyone blame the artist not the technology. This is why life music is still popular =P

Also Miles, no matter what your experience or personal opinion 30 years in a field does not make your right, check the ego at the door. You're a sheeple too.

 

[caster.cp]

I don't want to get in an argument about tubes vs transistors. That's really old and boring.

Constraining the argument to facts:

* Tubes add even harmonics to the signal. Have seen them. They're not some crazy fantasy of mine.
* Transistors are VERY, VERY lame when clipping occurs. Nothing that negative feedback doesn't solve.

People may be nostalgic and want to buy things that were good at the sixties. All right. I agree with all the arguments of ke5frf and Sceadwian.
I understand, as I said, that people may like the sound of a tube amp. I had a band once (in fact, I have played in three high-school bands, teenager stuff), and one friend of mine had a really good tube amp. I really liked its sound. But as an instrument amp. It really add warmth to the sound. And the tubes were really cool, at that time.

But I get mad when people mix High Fidelity with "sonic properties" (I get goosebumps when I hear that term).

I don't like any field that uses pseudo-science to prove anything. I don't like audiophiles. Shame on me.

I just don't see how people can say that transistors are bad. And I dislike it even more when people say that negative feedback is bad.

And I won't answer to miles because I really want this lame argument to end here. I understand I was rough on the comments and I apologise.

Those who think they know everything really annoy those of us who do

You made me laugh
I apologise again if I looked like I thought I knew everything. I really know very little about electronics. But I'm not just a newbie in a "newbie forum", that's for sure.


Sorry for bringing this really stupid argument up.

Castilho


edit: for those interested in the pro-transistor (lol) arguments, there are two good books about audio amplifier that I've read: High Power Audio Amplifier Construction Manual, by Randy Slone, and Audio Power Amplifier Design Handbook, by Douglas Self (this latter being the best of the two, in my opinion).

 

[Nigel Goodwin]

Constraining the argument to facts:

* Tubes add even harmonics to the signal. Have seen them. They're not some crazy fantasy of mine.

Exactly, they add unwanted distortion - that's what everyone has been telling you.

* Transistors are VERY, VERY lame when clipping occurs. Nothing that negative feedback doesn't solve.

No one has ever denied that either, but there's no need to run transistor amps in to clipping.