Tube and Solid State

[parapentep70]

To me, at a given power level, tubes sound naturally louder and nicer due to soft clipping (similar to advanced limiters in SS), the distortion happening when iron transformers go into saturation before they run out of voltage headroom (the resulting waveform is distorted but not stricly "clipped") and natural compression that could happen even at power supply level (reason for Mesa "triple rectifier" sound and the like).

Usually. And for a given # of watts.

However, at a given price / size / weight point any SS implementation (AB, H, D class) can do it everything above and will probably sound nicer and louder. In a big concert the bass can sound through a vintage tube amp, but finally reach your ears through SS FOH power amps. So they can reproduce the sound from the compressors (coming from tubes or SS), harmonic enhancers (tube or SS or DSP) and soft distortion / limiting circuits (limiters are usually implemented in the PA).

That's why somehow "I prefer the sound of tubes but I cannot see myself buying an all-tube amplifier". At a given price / weight there is always a SS implementation that does better for me than any tube rig.

Tubes in the pre are a different story, processing sound with a tube can be competitive (I did not say cheaper, but effective and simpler to use) than a DSP counterpart.

So for me, tubes, if any, in the pre-amp.

 

[seamonkey]

...
soft clipping
...

Solid state diodes do soft clipping.
Most of the guitar distortion pedals use diodes to do soft clipping. Distortion boxes can also be wired mini amps to do hard clipping. Both in the same box.

Both type of clipping are musical and have their place. And can be turned off when not needed if a pedal or modeler is used.

For those who want to compare some SS versus tube sound go pick up IK Amplitube free. It has both SS and Tube amp models. They also give you a couple of days trials for many other amp models in the Custom Shop. You can check differences within a brand, like Certified models of SS and tube from Ampeg.

Amplitube also has a version on iPod/iPad

 

[Duke21]

Solid state diodes do soft clipping.
Most of the guitar distortion pedals use diodes to do soft clipping. Distortion boxes can also be wired mini amps to do hard clipping. Both in the same box.

Both type of clipping are musical and have their place. And can be turned off when not needed if a pedal or modeler is used.

For those who want to compare some SS versus tube sound go pick up IK Amplitube free. It has both SS and Tube amp models. They also give you a couple of days trials for many other amp models in the Custom Shop. You can check differences within a brand, like Certified models of SS and tube from Ampeg.

Amplitube also has a version on iPod/iPad

And don't forget Sansamp products which contains about zero tubes, but emulate the tubes quite well.

 

[Oobly]

If You ant to see it....

Here is a link to bassic.ch, a german/swizz bassmens forum. The link leads to a thread where a guy constructed a real monster of a tube - bassamp, it delivers at least 950 Watt of pure tube power!

He uses some russian radio tubes, that are used in submarine radios with a fu**ing really high all-tube power output. The weight is about 60 KG.

The link: Invalid Link Removed

Holy smokes! Couple that to a fEARful 1515/66 and you'll start earthquakes!

Tubes tend to compress the signal as you start to push them and distort "musically" by rounding off the extremes of the signal instead of "clipping" them. So you can get a reasonably good tone while pushing the amp to a level that would be clipping and limiting on an SS. Just look at the TC RH450 and 750 for an SS that behaves similar to a tube amp. 236W that sounds like 750? From a solid state? Genius engineering. With a baked-in tone that can't be turned off. Like a tube amp. Pity they chose to lie about the specs instead of advertising the beautiful engineering.

 

[parapentep70]

Solid state diodes do soft clipping.
Most of the guitar distortion pedals use diodes to do soft clipping. Distortion boxes can also be wired mini amps to do hard clipping. Both in the same box.

Both type of clipping are musical and have their place. And can be turned off when not needed if a pedal or modeler is used.

For those who want to compare some SS versus tube sound go pick up IK Amplitube free. It has both SS and Tube amp models. They also give you a couple of days trials for many other amp models in the Custom Shop. You can check differences within a brand, like Certified models of SS and tube from Ampeg.

Amplitube also has a version on iPod/iPad

...Yes, I fully agree and I am glad you mention it.

Those circuits do the job... but not in the power stage. So if you want to keep this "nice sound" down to the loudspeaker you need extra headroom anyway. You shouldn't clip in a SS power stage after you "warm your sound" the way you describe.

This gets worse when you try to exactly replicate the output transformer saturation in bass region (which results in HIGHER crest factors in the output, not lower!). You'd need even MORE headroom.

So yes, in your opinion and also my opinion (not necessarily shared by everyone) you can get perfect "vintage sound" with diodes, BJTs (germanium vintage... crap or silicon) or JFETs or MOS up to very sophisticated DSP implementations.

But in order to put this sound on the speakers without the nasty clipping in the output stage, you will need need headroom.

This leads to the same conclusion: At the same watts, if distortion comes from the output stage you will sound the same but louder with a technology creating the "nice distortion" in the very output stage. If you try to push the SS to the same limit, you'll reach the clipping region and your sound will become nasty.

This is usual with modern DSP-based guitar amps. At home or rehearsing at low level they sound wonderfully. At gig level you crank up volume... you hit the SS poweramp clip point and all of a sudden your sound is really bad. Probably worse than using certain good old SS amplifier with softer clipping (less efficient).

Good PA systems implement limiters close to the power stage, so you have a softer clipping IN THE OUTPUT STAGE that will clip for sure at full power. TC RH450 / 750 extended this concept to the limit (Fully agree with Oobly, in fact I have the 750).

My original point was that at a given price / weight point SS will do it times better, processing sound before the poweramp stage and providing the required extra headroom at relatively low cost. Class D can do it very cheap.

At the end the sound of a vintage tube amp is amplified by SMPS / class D power stages in the FOH equipment and I've never heard a complaint about it.

 

[James Judson]

Tubes vs solid state. They are very different animals. Voltage makes a tube work. Current makes a transistor work. Tubes sound best cranked (even into clipping). SS sounds best before clipping. Study output curves and you find SS is most linear where there is no linearity with tubes. Yes even on the clean side tubes are still distorting (even order harmonics create a ringing, bell type distortion, very musical). Ever heard a telecaster twang, thats even order harmonics (distortion) doing that. On the dirty side of tube distortion or clipping (odd order harmonics create a brassy/buzzy sound, there again very musical). SS sounds great as long as the input sounds great to start with. Push a SS amp into clipping and it is not as musical.

Physically it takes a lot more hardware (tubes, sockets, transformers, power supply etc) to make a tube work. SS can be shrunk down to a micro chip with heat dissipation being the major critical factor. Its hard to compare SS vs tube unless you ignore all the BS that I just talked about and close your eyes and just use your ears.

 

[rockscott]

Ss has come a long long way over the years. I prefer it to tube myself. No maintenance, much lighter,portable and far more reliable!

 

[JimmyM]

Ss has come a long long way over the years. I prefer it to tube myself. No maintenance, much lighter,portable and far more reliable!

Sorry but that's bunk, except for the part about it coming a long way over the years and being lighter. There is absolutely zero evidence that tube amps are less reliable than SS amps. And if SS amps don't need maintenance, then why do I see plenty of SS amps at my local amp repair shop?

 

[gnjpowell]

Tube amps require output transformers to match the impedance of the tubes to the speakers, SS amps do not. More power requires larger transformers. The size, weight and cost of these output transformers puts an artificial and practical limit on the size of the output transformer and thus a limit on the maximum possible power output. SS amps do not have this limitation so very high power SS amps are far more practical and affordable Vs high power tube amps. Standard cost/benefit trade-off. As to relative reliability of SS Vs tubes, doing FOH sound I've encountered many a flaky or even totally failed SVT tube amp, never had a SS bass amp fail, yet... We supply a SVT-450H Classic (SS) with SVT-810 Classic for back-line for this very reason - they work and work reliably, look great on stage and the bass is almost always DI'd anyway. One bassist wanted to buy it on the spot and take it home with him that night.... no sale!

 

[rockscott]

Tubes get tired, and are expensive, its old technology imho!

 

[johnk_10]

Tubes get tired, and are expensive, its old technology imho!

yeah, after about 20 years or more.

funny how the new technology seems to be always attempting to mimic the old.

 

[Duke21]

Tubes get tired, and are expensive, its old technology imho!

Tubes are not that costy, and these tube amps are quite simple component wise. New Clas D amps are complex and look more like a PC inside. I think the amount of threads regarding failure in some SS amps are just about as common as tube amps. Old technology, yes but what a technology, every single SS amp out there try to emulate tube tone in one or other way.

 

[will33]

Somewhere along the way, this myth got propegated that tubes are unreliable or need to be changed often. I don't exactly where that, likely by folks who sell ss stuff but it is bunk. Tubes aren't sparkplugs. I've played on amps before that had tubes in them as old as me, (I'm 39). The most reliable, longest lasting amps I've owned myself are tube amps.

This whole "unreliable, expensive to maintain, keep needing to be worked on" thing needs to stop. It simply isn't true.

 

[ChrisPbass]

1971 Princeton Reverb....same power amp tubes. Sounds amazing too.

 

[JimmyM]

Tubes get tired, and are expensive, its old technology imho!

Invariably, the only folks who say that have never owned a tube amp in their lives.

 

[mikeswals]

Tubes get tired, and are expensive, its old technology imho!

But oddly enough, SS amp players all around me buy up new heads every 4-5 years or so. Far more sooner and frequent than me ever wearing out a set of tubes.

 

[seamonkey]

Somewhere along the way, this myth got propegated that tubes are unreliable or need to be changed often. I don't exactly where that, likely by folks who sell ss stuff but it is bunk. Tubes aren't sparkplugs. I've played on amps before that had tubes in them as old as me, (I'm 39). The most reliable, longest lasting amps I've owned myself are tube amps.

This whole "unreliable, expensive to maintain, keep needing to be worked on" thing needs to stop. It simply isn't true.

It's not a myth.

Start here:
Technical books online

"Getting the Most out of Vacuum Tubes" is a good read.

There's always going to be a few people who have an old TV or radio that has never had a problem. Somehow big internet sellers of tubes make a living from those socket mounted glass jars.

 

[scotch]

It's not a myth.

Start here:
Technical books online

"Getting the Most out of Vacuum Tubes" is a good read.

There's always going to be a few people who have an old TV or radio that has never had a problem. Somehow big internet sellers of tubes make a living from those socket mounted glass jars.

Reading a book is one way to learn some things about tubes and tube amps. Another great way to learn about them is to own and use them for decades.

Tubes can, and often do last for decades and continue to sound great! Sorry SeaMonkey. It's just the way it is.

Heck, even fighter planes managed to utilise vacuum tubes in critical circuits. I think a bass amp application is a smidge less demanding.

 

[mikeswals]

Somehow big internet sellers of tubes make a living from those socket mounted glass jars.

4 Wheel drive shops make a living off people who also like spending meaning less money...because they can. 99.8% of those trucks don't need lift kits and 38" tires.

 

[seamonkey]

...Yes, I fully agree and I am glad you mention it.
...

OK, all good

I'm not buying into the headroom argument. The SS amp just needs to reproduce a signal. They are cheap and easy to make with plenty of power. I guess it really doesn't matter.

Clipping in the FOH amps is not that bad. It happens. And they bi and tri amp. For subs you can clip high and mighty and not hear it.

If you're going to bother clipping. A good modern SS amp stays linear up to clipping. Clipping itself isn't linear but a good modern design does nothing but clip. It doesn't become unstable. This clip is not as bad as some on this would have you believe. There is some high frequency components to clipping, but this also is not as percentage wise as you'd think. 20% and you'd hear it but you wouldn't run for the hills. 10% and it's questionable if you hear it. 1% and you can't hear it. Extra high frequency comes from the input source, not from clipping itself.

Rane has a good technote on this
[Invalid or Expired Link Removed]

If you're going to drive into clipping then turn the treble down. Use tone controls for tone shapping with distortion anyhow.