I'm a Tube Amp Convert

[craigr]

Enough politics, let's talk audio.

Several weeks back on a lark I bought a used Audio Innovations Series 300mkII tube amp (AI300). This is an amp made by the now defunct Audio Innovations out of Britain probably in the early 1990s. It may be older than some of the readers here. I bought it to use in my office with my bookshelf speakers. The amp was in good condition and didn't need any refit work for capacitors, etc. which was a good thing. The tubes were on their last legs, but I replaced them recently.

This is a 10W amp and I got it for a price that I figured if it sucked I could just sell it again and not have to worry about it. But I was always curious to answer the question myself: Tube vs. Solid State - Which sounds better?

My home system features Bryston gear with a very nice Bryston 9B SST 5 channel power amp for surround sound. They power a front stereo set consisting of Dynaudio Contour 1.8MkIIs for the main left and right channels.

Well I plugged in the AI300 and let it warm up. Then I played some tunes from classical to electronic. I noticed that the AI300 had really good bass from my speakers (I don't use a subwoofer) with pipe organs. Same for electronic music. I then put in some vocals and piano and again it sounded really good.

I set out to do other things and came back later to do a real A/B swap between my tube AI300 and Bryston. It was not double blind, but I'm coming from an tech perspective that there is no way this tube amp was going to sound better than the Bryston. After all, this amp was going into my office and not my main listening room where the better Bryston was. Besides, Bryston is used in professional sound studios for mixing and was known for their neutrality to music.

Again I played various music and also setup a spectrum analyzer on my iphone just to double check what I was hearing. With a tone sweep the tube amp went down to 20-25Hz, but the Bryston didn't get below about 30-35Hz. So I was not hearing things, the tube amp gave better bass and the Brystons are known for good bass. A friend who was with me agreed that the tube sounded better than the Bryston.

Then listening to classical piano, vocals, etc. I swapped back and forth. My conclusion? The tube amp sounded better.

At least, for music it sounded better than the Bryston. I doubt technically on an oscilloscope it would be better, but musically it sounded really good.

The other thing is that the Bryston is true 150+ watts per channel (WPC). But the AI300 amp was only 10WPC. Yet, even at half volume the Tube amp was more than loud enough for anything I'd consider comfortable. At full volume I wouldn't want to be in the same room with it. The tubes seemed to drive the speakers really well. The Bryston is no slouch (and again I would never put it at full volume to save my ears), but I was impressed how well a 10W amp could drive the Dynaudios which are not that efficient (86db). This blew the myth of more power is better for average efficiency speakers out of the water for me.

This amp was maybe 1/10th the cost of the Bryston gear. But I have to reluctantly admit that for stereo use, I preferred the tube amp sound. I liked it so much I'm probably going to build a tube amp kit for my office and keep this amp for stereo music in my theater room.

Anyone else gone from solid state to tubes?

[Benko]

Craig,

"musically it sounded really good."
Yes, that is what tubes are known for.

I have several decades experience with high end audio, though I haven't looked at anything in probably 15 years.

There are vast differences in how electronics sound i.e. differences from one e.g. amp to another.

Decades and decades ago tube electronics and solid state electronics sounded very different and yes tubes were much better (at least for my tastes). last I looked you could get pretty close to the tube sound (or the advantages of tube sound without the disadvantages) If you chose the correct solid state amp*. I'm sure the state of the art has advanced and you can find the kind of sound you wish from solid state electronics though there is probably plenty of great sounding tube gear around as well. And unless you find the right solid state gear, picking any number of even old tube amps is likely to be be more musical sounding (and cost you less).


*Many of the "tube sounding" solid state amps used class A amplification either 100% of the time (in which case they weighed over 100 lbs and could literally heat your room), or operated with Class A amplification for the first 10 watts or so (where amps spend much of their time) and class AB above that.

[MachineGhost]

*Many of the "tube sounding" solid state amps used class A amplification either 100% of the time (in which case they weighed over 100 lbs and could literally heat your room), or operated with Class A amplification for the first 10 watts or so (where amps spend much of their time) and class AB above that.

Yes, I would bet that most solid states are Class D and just don't sound as good as Class A/AB. Class D are energy efficient but don't sound as natural whereas Class A/AB are fireplaces and sound great. I have a late vintage Pioneer receiver with conventional amplification but it was just too ridiculously big and hot to run passive bookshelf speakers sitting on my PC desk. What was the practical solution? Why, Class T of course! All I had to do was replace the provided wimpy power supply with a beefier monitor power supply to make sure everything actually had enough power. Its tiny and runs cool to touch. Oh sure, it may not have a 10KHz to 70KHz response with .05% THD as the receiver, but did I mention it was really, really, really, really freakin' inexpensive? You won't believe how cheap it is for the fidelity.

From 2009:

Tripath Technology TA2020 AudioAmplifier (1998)

There’s a subset of audiophiles who insist that vacuum tube–based amplifiers produce the best sound and always will. So when some in the audio community claimed that a solid-state class-D amp concocted by a Silicon Valley company called Tripath Technology delivered sound as warm and vibrant as tube amps, it was a big deal. Tripath’s trick was to use a 50-megahertz sampling system to drive the amplifier. The company boasted that its TA2020 performed better and cost much less than any comparable solid-state amp. To show off the chip at trade shows, “we’d play that song—that very romantic one from Titanic ,” says Adya Tripathi, Tripath’s founder. Like most class-D amps, the 2020 was very power efficient; it didn’t require a heat sink and could use a compact package. Tripath’s low-end, 15-watt version of the TA2020 sold for US $3 and was used in boom boxes and ministereos. Other versions—the most powerful had a 1000-W output—were used in home theaters, high-end audio systems, and TV sets by Sony, Sharp, Toshiba, and others. Eventually, the big semiconductor companies caught up, creating similar chips and sending Tripath into oblivion. Its chips, however, developed a devoted cult following. Audio-amp kits and products based on the TA2020 are still available from such companies as 41 Hz Audio, Sure Electronics, and Winsome Labs.

Source: http://spectrum.ieee.org/semiconductors ... -the-world

Amazon doesn't sell a newer version anymore, but it's still available from here:
http://www.parts-express.com/lepai-lp-2 ... y--310-300

[craigr]

I'd agree that many solid state amps today sound very good. Even my Bryston separates are going to be on the chopping block soon to be replaced with a modern Yamaha Aventage all in one receiver just to simplify things. I need to audition it to see how it compares first.

But I have to admit, I like the look of glowing tubes. I think they are just a wonderful thing to look at close up with the details and workmanship in good tubes.

As luck would have it, there is someone near me that has a collection of 300,000(!) [not a typo] tubes. He hooked me up for a good price with a complete replacement set of Toshiba ECL86s for the power tubes, and a Telefunken and Mullard 12AU7 to play with for the pre-amp section.

I recently was able to borrow from him a Chinese made tube amp, and I'd have to say not only was it reasonably priced, but sounded damn good as well.

On my desk I had some Audioengine A5s. They have now been replaced with a set of Dynaudio 2/6 bookshelves with the AI300 tube amp for now. This new combo sounds much better than the A5s after a comparison, which are pretty good speakers otherwise. The Dynaudio and tube amp just had them beat.

To make matters worse, my headphones for my computer are Stax SR-407s which sound excellent. But now that I run the tube amp and Dynaudios at my desk, I find that the Stax are almost too bright.

[ochotona]

Sounds like a bunch of hams talking about their HF linear amplifiers!

[Libertarian666]

Ok, since we're talking audio, would it be all right for me to mention that I have a couple of items for sale?

[craigr]

Ok, since we're talking audio, would it be all right for me to mention that I have a couple of items for sale?

Only if they are tube amps.

[Libertarian666]

Ok, since we're talking audio, would it be all right for me to mention that I have a couple of items for sale?

Only if they are tube amps.

I guess I'm out of luck then.

[MachineGhost]

Tube amplifiers sound better because of the euphonic distortions they add to the music, as well as plenty of other reasons I'll cover below.

These are subtle effects most audible to musicians and very dedicated music lovers; casual listeners (people who "listen" with their eyes open while doing something else) usually won't notice, but sometimes the difference is so obvious that people's wives will comment that "wow, that sounds much better" when people use tubes at home.

Tube amplifiers measure poorly in the lab specifically because of these added distortions, but these distortions are often a part of what make them sound better.

Even today with an all-digital infrastructure from recording studio to home, professional studio microphones for decades and decades and decades have used tube pre-preamplifiers inside the microphones themselves. Today their outputs are fed to tube preamplifiers before being digitised for recording, mixing and distribution. We use tubes simply because they make the music we create sound better: smoother, warmer and cleaner.

Ditto for guitar amplifiers used in creating music. The ways that tubes distort when pushed to the edge are much more musical than the artificial sounds that come from transistor amplifiers when overdriven. Some transistor guitar amplifiers attempt to mimic tube distortion, but that's a different article.

Of course these are all very broad generalizations, and this is just as much due to circuit designs used with tubes or transistors as the devices themselves, but what are the distortions and other reasons tube amplifiers sound better?

Full Story: http://kenrockwell.com/audio/why-tubes-sound-better.htm

[Cortopassi]

I am surprised anyone cares anymore...

When you hook up your tube amp to your AV system, makes sure you use cables from this company:

https://www.amazon.com/gp/product/B00IL ... z_bw_c_x_2

(read the comments and look at others, good for a lot of laughs)

[craigr]

Sadly, I just use 12 gauge zip wire I bought at the hardware store to hookup my speakers. I'm wondering if it's causing electron misalignment and I should upgrade?

[Lonestar]

Ok, since we're talking audio, would it be all right for me to mention that I have a couple of items for sale?

Only if they are tube amps.

Then, while we are on the subject, how could I find out how much an old Harman Kardon Award Series A700 70 watt amp would be worth? Are there any forums out there for tube type amp enthusiasts? I got one that's been stored 35 years that I need to get rid of.

http://www.radiomuseum.org/r/harman_awa ... _a700.html

[craigr]

I suspect there are vintage amp collectors out there. E-Bay would be the first place I'd look and let the market decide. If the amp works that is a big plus. Start the auction at $1 with no reserve and see what happens.

[MediumTex]

Sadly, I just use 12 gauge zip wire I bought at the hardware store to hookup my speakers. I'm wondering if it's causing electron misalignment and I should upgrade?

It wouldn't surprise me at all if you were suffering from electron misalignment.

Only expensive cables can properly align the electrons (or at least that's what the guy in the stereo shop told me ).

[MachineGhost]

It wouldn't surprise me at all if you were suffering from electron misalignment.

Only expensive cables can properly align the electrons (or at least that's what the guy in the stereo shop told me ).

It's objective!

Our research shows there really is no best speaker cable. But the Monoprice 2747 12 gauge is the speaker wire I’d buy. I base this on extensive research on available cables and actual listening tests. The 2747 offers excellent value, solid construction, and, perhaps most importantly (and surprisingly), better sound quality. But keep in mind that this is the least important piece of gear in your entire home theater setup and the impact it makes is negligible.

Source: http://thewirecutter.com/reviews/the-be ... ker-cable/

[craigr]

Best write-up on cables was an old post from John Dunlavy of Dunlavy Audio Labs:

http://www.verber.com/mark/ce/cables.html

Oh yes, we have heard of golden-eared audiophiles who claim to be able to consistently identify huge, audible differences between cables. But when these experts have visited our facility and were put to the test under carefully-controlled conditions, they invariably failed to yield a score any better than chance. For example, when led to believe that three popular cables were being compared, varying in size from a high-quality 12 AWG ZIP-CORD to a high-tech looking cable with a diameter exceeding an inch, the largest and sexiest looking cable always scored best - even though the CABLES WERE NEVER CHANGED and they listened to the ZIP Cord the entire time.

That's why I just use zip cord.

I made my RCA interconnects with Canare cables and Neutrik connectors myself based on recommendations given to me by James Tanner of Bryston. That's what they basically produce and sell to pro users that need RCA connectors but you can make them yourself for far less money than buying them:

http://bryston.com/products/other/RCA.html

[MachineGhost]

I made my RCA interconnects with Canare cables and Neutrik connectors myself based on recommendations given to me by James Tanner of Bryston. That's what they basically produce and sell to pro users that need RCA connectors but you can make them yourself for far less money than buying them:

http://bryston.com/products/other/RCA.html

I've been fine using RG6 coaxial cables with F-pin female jack to RCA male plugs at each end. Verryy stiff, though! And cost probably one teneth of what Monster Cable or others hucksters would charge. The AWG was 18. RG11 is 14 AWG.

Is there any harmony in matching interconnect with speaker AWG?

[Benko]

There are websites which specialize in people selling high end audio equipment (direct from seller to buyer) that you can sell gear on or search old ads to see how much people were asking. Here is one:

https://www.audiogon.com/listings?order ... ed_at+DESC

though you can probably find others with google.


Craig, absence of evidence, is not the same as evidence of absence i.e. just because you can't prove it with double blind hearing trial (or one trial) doesn't mean it isn't true. Which does not mean that I'd buy the most expensive cable either. If I was going to buy an amp for several hundred dollars I'd look for a good basic cable e.g. 20-30$ or so. Here is a place that will lend at least people who live in the US different cables they can try at home:

https://www.thecableco.com/content.aspx?iid=5777

and they've been around since 1989. They could probably suggest an inexpensive basic cable if you wished.