Tube or solid state?

DVV · « **Reply #100 on:** 4 Feb 2003, 10:14 pm »

Quote from: JohnR

DVV, I don't read high-end rags any more, but last time I looked they were full of misleading ads for just about everything. I had no idea that tubes had become such an evil influence all by themselves Too bad because they're a lot of fun. Why don't you show us an actual example of this horrendous crime that's being perpetrated right under our noses? I'm curious now. ...

I don't need to - just go out and buy a mag purporting to deal with "high end" audio, any mag, US, or UK, or German, or Italian, or ...

More than that - entire magazines are devoted to this. I still keep a German mag somewhere exactly along these lines, must be 2 years old. A glaring example, though others are not quite as bad as that.

But John, make no mistake, SS has its own problems as well. Consider the so-called "minimalist" camp, preaching the KISS (Keep It Simple Stupid) principle. They give you a teeny-weeny board with as few components as they could manage and still have it working, these boards not actually costin over say $100 each per channel. Then, in the best spirit of minimalism, they unload a front plate 1 inch thick, costing $150 all by itself - before machining. And a hefty case, also costing like 2-3 times the electronics inside. You end up paying 10-20% for the electronics, 20-25% for the case, and the rest for graft, advertising and other "unforeseen" costs.

So what you buyin', dude? You in the scrap metal business? If not, they make you get into it. Hey, we all like to see some nicely machined parts, yes, but who really needs a 1 inch thick front plate? Or could it be they are using it to pull wool over your eyes?

Just different takes by the two camps, but all pointing the same way - to your wallet. Whatever happened to value for money?

Cheers,
DVV

nathanm · « **Reply #101 on:** 4 Feb 2003, 10:54 pm »

Speaking of minimalist, you can buy those passive volume pots screwed into a project box for a few hundred bucks! Sheesh! Hey, I'm all for full-ass parts but holy smokes, that's a lot of cash for a knob! What's all in those things anyway?

KevinW · « **Reply #102 on:** 5 Feb 2003, 01:31 am »

Quote from: DVV

Just different takes by the two camps, but all pointing the same way - to your wallet. Whatever happened to value for money?

Dejan,
I thought that is what the internet was for... to circumvent the stereo-mag markup scam by giving access directly to the manufacturers and some of the more reputable dealers? I would say that most of the people on this forum are probably getting great value for their money! Makes me wonder why you're ranting on this so hard and saying that it doesn't even exist.

JohnR · « **Reply #103 on:** 5 Feb 2003, 03:14 am »

Quote from: DVV

Whatever happened to value for money?

I dunno, but is this what you are referring to?

http://www.sakurasystems.com/products/47amp.html

DVV · « **Reply #104 on:** 5 Feb 2003, 07:48 am »

Quote from: KevinW

Quote from: DVV

Just different takes by the two camps, but all pointing the same way - to your wallet. Whatever happened to value for money?

Dejan,
I thought that is what the internet was for... to circumvent the stereo-mag markup scam by giving access directly to the manufacturers and some of the more reputable dealers? I would say that most of the people on this forum are probably getting great value for their money! Makes me wonder why you're ranting on this so hard and saying that it doesn't even exist.

No Kevin, I'm not saying it doesn't exist, I am saying there are many out there trying to surpress it as hard as they can because they stand to gain from it. All I'm trying to do is reinstate it as THE key factor.

Obviously, if you want more, you'll need to pay more; what I object to is adding a cheap, 30 cent op amp and then charging the public an extra $100 for this. I am wondering about proportional costs - $200 for the electronics and $300 for the case. I am wondering about dogmas - the way I see it, any dogma is bad, yet I see new dogmas being created, where somebody obviously profits.

Cheers,
DVV

DVV · « **Reply #105 on:** 5 Feb 2003, 07:53 am »

Quote from: JohnR

Quote from: DVV
Whatever happened to value for money?

I dunno, but is this what you are referring to?

http://www.sakurasystems.com/products/47amp.html

To be able to answer that, John, I would have had to have heard the GainCard. Unfortunately, I have not heard it, and I have no idea what it costs, so obviously, I can't answer the question.

In general, I agree circuits should not be any more complex than they have to be - so long as they can still perform the intended function well. If those people can make a good sounding amp with just 9 parts, kudos to them, I'd call that some creative engineering.

Cheers,
DVV

JohnR · « **Reply #106 on:** 5 Feb 2003, 08:40 am »

It costs $3300. One of the nine parts is an op-amp.

JohnR

nathanm · « **Reply #107 on:** 5 Feb 2003, 05:49 pm »

Sounds like those bikinis in the SI swimsuit issue - the less there is of them the more expensive they get!

Well a 3 grand volume control is a bargain compared to the $25,000 CD spinner. The stuff looks full-ass though, I'll give it that. I like machined metal!

25 grand would make a nice down payment on a new listening room though!

DVV · « **Reply #108 on:** 5 Feb 2003, 09:42 pm »

Quote from: JohnR

It costs $3300. One of the nine parts is an op-amp.

JohnR

3.3K for 2x9 components? Wow, that's some economics for you! 1 will get you 10 the case costs more than the elctronics.

But it's a good example - somebody please explain to me the value for money here.

Cheers,
DVV

tmd · « **Reply #109 on:** 5 Feb 2003, 09:53 pm »

Someone please get this thread back on track

We have gone away from tubes versus solid state a little. I think we all accept that people spend too much on hype all the time. I personally haven't seen the distinction between SS and Tube hype. I think you can spend way too much on either. I have been witness to someone wanting to spend $20,000 on a pair of speakers after a five minute listen and couldn't be talked out of it no matter what. I figure the purchase was for bragging rights only. It just can't be helped.
I realised before I bought my first piece of real audio gear that there is value to be had, thanks ONLY to the internet and people who were prepared to help. I say let the idiots who have money to piss down the drain do it!!!!!
Neil.

DVV · « **Reply #110 on:** 6 Feb 2003, 07:47 am »

Quote from: tmd

Someone please get this thread back on track
We have gone away from tubes versus solid state a little. I think we all accept that people spend too much on hype all the time. I personally haven't seen the distinction between SS and Tube hype. I think you can spend way too much on either. I have been witness to someone wanting to spend $20,000 on a pair of speakers after a five minute listen and couldn't be talked out of it no matter what. I figure the purchase was for bragging rights only. It just can't be helped.
I realised before I bought my first piece of real audio gear that there is value to be had, thanks ONLY to the internet and people who were prepared to help. I say let the idiots who have money to piss down the drain do it!!!!!
Neil.

Amen!

Cheers,
DVV

JoeM · « **Reply #111 on:** 8 Feb 2003, 04:15 pm »

Funny how this question always seems to get the juices flowing in most any forum. I suppose there is no right or wrong answer, it's a matter of personal bias. Being firmly in the tube camp at this point does not preclude my involvement with solid state. In fact, I've just ordered a Aria WT-100 hybrid for audition. Why? Because as much as I prefer the sound of tube amps (BAT VK-60 monos in my case), I think a large number of tubes present too many variables in one's system. At one point there were 63 tubes IMS! I've downsized that number considerably since and I'm happier for it. I've got my fingers crossed and hope the hybrid solution will work for me. If push came to shove (or is that push came to pull?), I could probably live with the right solid state amp happily. Maybe.

DVV · « **Reply #112 on:** 8 Feb 2003, 07:21 pm »

Quote from: JoeM

Funny how this question always seems to get the juices flowing in most any forum. I suppose there is no right or wrong answer, it's a matter of personal bias. Being firmly in the tube camp at this point does not preclude my involvement with solid state. In fact, I've just ordered a Aria WT-100 hybrid for audition. Why? Because as much as I prefer the sound of tube amps (BAT VK-60 monos in my case), I think a large number of tubes present too many variables in one's system. At one point there were 63 tubes IMS! I've downsized that number considerably since and I'm happier for it. I've got my fingers crossed and hope the hybrid solution will work for me. If push came to shove (or is that push came to pull?), I could probably live with the right solid state amp happily. Maybe.

Of course you, just as I could live with a good tube system - so long as we don't get partisan about tube or SS. In other words, so long as it stays all about music, not technology, or equipment for equipment's sake.

I started this forum simply to learn what other people think, not to start a war, which thank God didn't happen. Reading back, we did get an uncommonly large number of well thought our posts, something I must admit I have never seen yet until now. And something I'm very pleased with, I have to say it. To me, this means serious participants, and that in turn means people I should listen to before making up my mind.

It all boils down to how one looks at it. In my case, differences of opinion are not only not sanctioned, but are in fact invited. I believe in feedback, and all by myself and people who think along similar lines, I have no feedback. To me, differences serve to make us richer, not as an excuse to shoot somebody. That's what I wanted, that's what I got - and feel better for it.

Cheers,
DVV

AKSA · « **Reply #113 on:** 11 Feb 2003, 11:00 am »

Here's a few observations on tube V. SS.

Tubes:

1. If configured properly, introduce a lower order distortion spectrum which adds 'warmth' and 'grace', largely because of their transfer function and (normally) an absence of feedback.
2. Are arguably the best voltage amplifers in the science of electronics.
3. Operate at high voltage and low current, meaning high impedance, and thus have huge problems driving speakers of low impedance directly. They need transformers, and this complicates thing enormously.
4. Are electrostatic devices, and thus are highly susceptible to hum intrusion.
5. Interact hugely with their power supplies, making their proper use an art form.
6. Steadily burn out from the day they are switched on. This problem is very problematic with large bottles used for power stages.
7. Are staggeringly robust electrically, if not mechanically. The ruskies used them in all their military equipment because they resist EM burst from nuclear explosions.
8. Can be frighteningly expensive, cf. the WE 300B and 845.

Transistors:

1. Have huge current gain (beta) and thus must be operated with feedback, either local or global. Both are commonly used, with global feedback having many problems.
2. Are aguably the best current amplifiers in the business.
3. Have a different transfer function to tubes, which creates a very different distortion spectrum, depending on how they are configured, of course. Typically, SS is more accurate.
4. Display low impedance characteristics; emitter source impedance is typically given as 26 / emitter current (mA); thus a 1A device has an emitter source impedance measured in milliohms. Great for driving loudspeakers directly!
5. Are incredibly tough mechanically, if a little fragile electrically.......
6. Extremely inexpensive - a wonderful boon.
7. Microscopic in size, facilitating huge complexity in tiny space, viz integrated circuits, a marvel of modern life.
8. With feedback and certain other tricks, capable of stunning resolution, important particularly in complex, orchestral music.

There! Enough differences?

My own feeling is that the ideal audio amplifier, one designed for high resolution and vivid portrayal of musical color and emotion, is a hybrid, using tubes for voltage amplification, and SS devices, probably mosfets, for current amplification. I love 'em both........

Cheers,

Hugh

audiojerry · « **Reply #114 on:** 11 Feb 2003, 01:55 pm »

Hugh wrote:

Quote

Transistors:
1. Have huge current gain (beta) and thus must be operated with feedback, either local or global. Both are commonly used, with global feedback having many problems.

Thanks for the lesson; that was very helpful. Could you explain why high current requires more feedback?

Quote

My own feeling is that the ideal audio amplifier, one designed for high resolution and vivid portrayal of musical color and emotion, is a hybrid, using tubes for voltage amplification, and SS devices, probably mosfets, for current amplification. I love 'em both........

Not to be obnoxious, but it sounds like the description of Van Alstine amps. I heard the execution of an earlier Van Alstine model recently thanks to Jackman, and I must admit, its performance bore a close resemblence to my much more expensive Audio Research all tube design. It seemed to have excellent drive and bass control. This description was taken from the Van Alstine website, www.avahifi.com:

Quote

Our hybrid vacuum tube design sounds so real because it lets the individual gain parts each work in optimum environments. Vacuum tubes are great at manipulating voltages—you can play with 200+ volt signals where transistors would go up in smoke and flames. So, we use vacuum tubes for all voltage manipulations. Vacuum tubes, however, cannot drive difficult loads. They have very limited output current and get in big trouble trying to drive feedback loops, stray internal capacitances, and connection cables. So, we don’t let our tubes see any loads at all. They operate in an idealized mode amplifying voltages only, and do it perfectly.

Power MOSFETs are super current amplifiers. They can control great gobs of current without stress, and when properly selected and used, they perform without needing external compensation, thermal tracking circuits, or VI limiting and protect circuits. So we use all power MOSFETs for current-amplification duties. There is simply no roughness or compression in Fet Valve amplifiers.

Our power supply features a shielded toroid power transformer and a regulated 12 volt heater supply for the vacuum tubes. The tubes see no AC ripple at all and thus have vastly extended service lives. There is a separate six-stage power supply for the active circuits with isolated supply sections for each tube and hybrid section of each channel.

Unlike other tube-MOSFET hybrids, our tube sections do not have to directly drive MOSFETs connected to real world loads, thus the tubes never load down as they are doubly isolated from the real world.

I'm not trying to promote Van Alstine. Instead it woud be interesting to get commentary from our three resident guru's. Since this thread involves discussion about different approaches to amp design, I hope my post isn't out of line.

Dan Banquer · « **Reply #115 on:** 11 Feb 2003, 02:19 pm »

I'm not a real big fan of power FETS for audio. The first problems are linearity and complimentarity. The lack of complementarity in N channel and P channel makes Bipolar transistors look good by comparison. The great bulk of power FETS that are produced are designed for switching power supplies. The great bulk of these are N channel FETS. The lack of complementarity between the two will cause linearity problems in output stages.
The second problem is the input capacitance from either gate to drain or gate to source. This is much higher than the great bulk of bipolar transistors.
I suspect more feedback will have to be used to "linearize" the output FETS than bipolars.
One last and hopefully final statement on global feedback. It's not the feedback; it's the amp inside the feedback loop. Audio has been blasting away at global feedback because it has beeen misused by so many. Just to give some anecdotal evidence. Some of my customers compare my amps the Jeff Rolands in sound quality. Roland uses the Hawksford distortion correction circuit and I use global feedback. Go Figure.
And if John R. needs more than anecdotal evidence I will be happy to bury him with it.

audiojerry · « **Reply #116 on:** 11 Feb 2003, 03:00 pm »

I wish I knew enough to understand what Dan just said...

Dan, is the issue you have taken with FET's the reason why hybrids is a bad concept, or does it have nothing to do with hybrids?

Do you believe the hybrid concept is a bad idea?

Dan Banquer · « **Reply #117 on:** 11 Feb 2003, 03:22 pm »

Hi Jerry;
I am not a big fan of hybrids or tubes. I was trying to point out that FETS aren't exactly ideal devices either. Try thinking of it this way: There is no free lunch. This is engineering and there are cause and effect relationships, as well as price vs. performance relationships. It's the best I can do for the moment.

audiojerry · « **Reply #118 on:** 11 Feb 2003, 05:14 pm »

So philosophically, bipolar is inherently better than mosfet or jfet?

Dan Banquer · « **Reply #119 on:** 11 Feb 2003, 05:33 pm »

When you look at all the pro's and con's, bipolar output transistors really come out on top as far as I am concerned. J Fets are used as input devices, and can be pretty good in many situations. I have used them in the past and will probably use them in the future.