Once you go VAC you never go back.

[midnightmayhem]

I have been experimenting with Hi-Fi since I was about 12 or 14 years old. Always with solid state. Finally got the wild hair to try a tube amp setup when i was in high school and promptly decided that i could not afford it. Im 26 now and have owned more stereo equipment than I care to remember. About a year ago I was granted the opportunity to get in to tubes. I bought an old Bogen chasis at the flea market for $70 american. It needed lots of work and it came without tubes. I rebuilt the power supply replaced all the missing tubes and replaced all the RCA's and speaker connectors with nice gold plated units. For what Iv got into it (about $350) it sounds so far beyond anything I'v ever owned I cant go back. Im starting to question the hearing ability of those who think their solid state system sounds good, or produces bass. I never knew how absolutely terrible distorted "sand" bass sounded until I heard the tubes producing powerful bass without clipping. When visiting friends who have way more into their systems than I do I hold my tounge because they worked hard for what they have. Is it all in my head? A matter of personal preferance? or is it My hearing that is damaged. How is it that 12 watts of tube power can give a brand new 100 wpc amp an embarrassing lesson in clipping. Im running a Vintage pioneer table or a a vintage technics table, and a set of the original Advent loudspeakers. Nothing Real special.

[MonkeyBoy]

It isn't the first time I have read about someone having a low watt tube amp show a higher watt SS amp how to handle clipping. I'm thinking about building one for myself.

I can't help but wonder how much headroom the SS amps you are comparing it to had. I do know the SS amp I have now has very natural sounding bass, but then, it is an amp that I tested against others before buying and it has loads of headroom.

I may just start with a tube phono pre as I upgrade my analog section.

[PeterW.]

It isn't the first time I have read about someone having a low watt tube amp show a higher watt SS amp how to handle clipping. I'm thinking about building one for myself.

Conventional tube amps clip softly - and the Bogen the OP mentions is about as conventional as it gets. As they use output transformers, they cannot pass DC directly to the speakers.

I can't help but wonder how much headroom the SS amps you are comparing it to had. I do know the SS amp I have now has very natural sounding bass, but then, it is an amp that I tested against others before buying and it has loads of headroom.

And that is the key to the difference between similarly rated tube & SS amps. A 20 wpc tube amp will sound very much better than a similar SS amp (or even a 40-watt SS amp) if driven to the margins - and at a much lower risk to the speakers. Pick a similar-vintage SS amp such as the Dynaco ST-120 or ST-80. Driven to clipping, they will pass DC to the speakers. Ouch!!

I may just start with a tube phono pre as I upgrade my analog section.

With respect, a tube phono-pre/head amp is perhaps the least effective place to start with tubes. Start with a power-amp first. Really. Yes, the venerable Dynaco PAS-3 has a very nice tube phono-stage consisting of one (1) 12AX7 (dual-triode) per channel. But whatever you achieve at that stage (other than distortion artifacts) will be more-or-less erased further down the line. Start with the amp. If you like the effect, move on to a tuner. If you like that effect, move on to a pre-amp with an included phono stage - and you could do a great deal worse than the PAS previously mentioned.

It is my considered opinion that every serious audio enthusiast - especially those dabbling in tubes - should own a Dynaco ST-70. They are well-supported in the after-market, every part and piece in them is readily available and all sorts of upgrades (real and imagined) are available. Their FM-3 enjoys a similar condition as a tuner, and the PAS ain't half-bad either.

Peter Wieck
Melrose Park, PA

[cocoabaroque]

There are well designed solid-state amps, including many of the newer chip based designs (LM1875, LM3875, etc) that have great sound. Ive compared to single ended tube amps using 6bq5, EL34, 6BM8 and more. Different sounding, but if pressed, I'd say the current generation amps are much more neutral sounding than 1980s mosfets, and most (but not all) jfets. As good as the best tube gear, only less tubey sounding. I like chipamp.com (DALaudio) but many other imports available too.

[PeterW.]

Single-ended tube amps - OK. That pretty much excludes any reasonable discussion right there!

Oh, I thought all SE amps were supposed to be Triode based (SET) based on something like the 71A or 2A3??? Not a common-as-dirt pentode!?!

Peter Wieck
Melrose Park, PA

[steve195527]

best amp I have ever heard(or not heard:-a good amp shouldn't really have a sound)of any type was the Yamaha B-1,by quite a large margin:-apparently the guy who originally designed it for Yamaha is making it again under his own banner

[satanfriendly]

Sorry I've lived with bottles and each time returned to SS. The only tubes I've heard which make me sit up and take notice are in the mortgage bracket.

Great if you do like them, but not for me.

If you can drive either of my present amps in to clipping I'd be highly surprised or deaf.

[LPfan]

Is this a Bogen DB212 ?

Regards,

LPfan

[midnightmayhem]

It is a bogen AP-35, I love it. If I were to use a solid state amplifier I would be required (by my finances) to fix it when it breaks. Not going to claim that tube amps are trouble free by any means but when I do have trouble I can fix it without causing any colateral damage, or guessing! When I try to fix solid state stuff I sometimes cannot find the problem and when dealing with such sensitive components it is really easy to toast the whole unit by accident. I guess you could argue that tube amps will toast the technician before the tech toasts the amp. Long story short Im really enjoying myself, I have not listened to everything ever produced, and I keep an open mind. As of right now I dont see myself replacing my tube amp with anything (tube or solid state) simply due to the fact that it sounds so nice to my ears.

[JoeE SP9]

Conventional thought has always been that the earlier the tubes are in the chain the greater the beneficial effect they will have. That's why many people use a tubed preamp with a SS power amp. I use SS for my subs and tubes for my esl's

[duficity]

Tube amplifiers tend to distort the second harmonics, SS tends to distort the third harmonics. Second Harmonics are more pleasing to our ears, so when a tube amp distorts, it doesnt sound terrible. when a SS distorts, it does sound terrible and as you increase volume, it doesnt get louder, just more distortion. A SS amp needs a much better power supply and headroom, IMO. I avoid any SS amp that cant double its power into 4 ohms and quadruple into 2 ohms. to me, that means a compromised power supply. And you would be surprised how many 8 ohm speakers dip down below 4 ohms at some point in their frequency response.

[steve195527]

Tube amplifiers tend to distort the second harmonics, SS tends to distort the third harmonics. Second Harmonics are more pleasing to our ears, so when a tube amp distorts, it doesnt sound terrible. when a SS distorts, it does sound terrible and as you increase volume, it doesnt get louder, just more distortion. A SS amp needs a much better power supply and headroom, IMO. I avoid any SS amp that cant double its power into 4 ohms and quadruple into 2 ohms. to me, that means a compromised power supply. And you would be surprised how many 8 ohm speakers dip down below 4 ohms at some point in their frequency response.

think you have read too much Krell advertising bumph re power doubling with 1/2ing of impedence,the Chord amps don't double but you will struggle to find another SS amp that sounds better:-lots of studios seem to agree as well!
Because of the characteristics of valves v most transistors it is easier to build a "good sounding" valve amp than it is a SS amp,on a personal note most valve amps sound great in the mid/high areas but not in the bass unless you spend a lot of cash,did own a pair of EAR 509's a while back that were good in all areas but they were expensive at the time

[cafe latte]

I have been experimenting with Hi-Fi since I was about 12 or 14 years old. Always with solid state. Finally got the wild hair to try a tube amp setup when i was in high school and promptly decided that i could not afford it. Im 26 now and have owned more stereo equipment than I care to remember. About a year ago I was granted the opportunity to get in to tubes. I bought an old Bogen chasis at the flea market for $70 american. It needed lots of work and it came without tubes. I rebuilt the power supply replaced all the missing tubes and replaced all the RCA's and speaker connectors with nice gold plated units. For what Iv got into it (about $350) it sounds so far beyond anything I'v ever owned I cant go back. Im starting to question the hearing ability of those who think their solid state system sounds good, or produces bass. I never knew how absolutely terrible distorted "sand" bass sounded until I heard the tubes producing powerful bass without clipping. When visiting friends who have way more into their systems than I do I hold my tounge because they worked hard for what they have. Is it all in my head? A matter of personal preferance? or is it My hearing that is damaged. How is it that 12 watts of tube power can give a brand new 100 wpc amp an embarrassing lesson in clipping. Im running a Vintage pioneer table or a a vintage technics table, and a set of the original Advent loudspeakers. Nothing Real special.

I have had quite a few valve amps over the years including classic quads and also Leak stereo 20's, now i have a massive Ming da (25kg) with 300b valves in it, but I also build my own transistor amps. I currently have 3, a 10wpc class A another class A transistor which is 46wpc but a single ended design sort of anyway, and a mosfet 180wpc biased into class A for the first 15w or so. What is the best amp I have ever had? The mosfet actually as the bass is very clean not bloated as valves can be and the treble is very clean. My friend has a Conrad Johnson valve amp which I had for a while as I fixed it after he blew it up this was one of the few valve amps that I have ever heard that could do bass without making it bloated, an amazing amp but it too had its downfalls. What I am trying to get at is neither one is better than the other transistors and valves are just two ways of doing the same thing and there are very good and very poor examples of both.
Regards
CL

[Coffee Phil]

This amplifier thing can be like arguing religion or politics.

My belief is that there good amps and there the other kind. I think that with most tube amps which use output transformers and AC coupling between the stages it is not possible to use copious amounts of feedback to get good distortion numbers so designers are forced to achieve low distortion before applying feedback. Also most vacuum tube class AB push-pull amplifiers are essentially class A at low power levels. With class AB solid state amps (especially bipolar) it is hard to avoid thermal run-away with the amp biased heavy toward class A at low power.

I do believe that in the early days of solid state amps tube amps with even higher distortion numbers would blow away the solid state amps. Now I like tube amps, but I don't believe that they are inherently better than solid state amps. My Citation 5 was down for several months while I rebuilt its power supply. In its absence I used a BTL solid state amp which I built some years back. It has about 1/2 the power of the Citation 5 but at levels within its capability I think it sounded similar. Back when I designed the the little BTL amp I was careful about how I applied feedback.

When I finish my stereo room the amplification will be tubes from my phono cartridge to the main speakers. The sub will be driven with a MOSFET amp however. I don't for a minute believe that the sound can't be equaled with less effort using solid state components. I'm just an old guy and I like tubes. Even with that said there will be solid state stuff such as the video stuff and my CD player. Also my mono phono stage with the selectable EQ and vertical / lateral switching is here to stay. I'm sure I could design and build a tube unit to emulate it but I have other projects so it may not happen.

Phil