Tube power amps

[Polka1]

I never used power section distortion as part of my palette. So, while I completely adore the SVT running in clean mode, I’m also more than good with a tube preamp driving a clean solid state power section. As long as it’s clean and slams, it’s good. There are both tube and solid state power sections that get that thing done.

It's generally pretty hard to run an SVT loud enough to achieve significant power section distortion, especially with an 8x10 or two 8x10s.

Interestingly enough, years ago, I had my SVT-2 power section blow up before a gig. My tech disabled it and we ran the SVT preamp out directly into a PA power amp (A Crown amp, if I recall correctly) and then into the same 8x10 as I was using before. It sounded different. Not bad exactly, just different. This compared clean to clean. It moved from SVT realm to slightly GKish. More articulate and slightly square around the edges. It was enough that my friends in the crowd noticed the difference, not just me being critical.

Back to the original poll: are the big tubes worth it? To me, yes. There is something really nice about the sound that I haven't found elsewhere. However, the world won't fall apart without them. And at the same time, yes - things do go bad with tube power amps more often.

 

[Freight Train]

I've seen people saying the preamp tubes is all that matters to them, so i'd like to know some opinions about it

Edit: I'm seeking opinions from those who think tube amps sound better already, to know what they are talking about when they say tubes are better. Not bashing solid state in any way

I chased my tail for decades trying to replicate a bass sound I was hearing in recordings and in my head by using all mannerr of preamps and overdrives, both tube and solid state. It wasn't until I was able to play a low-powered (100 watt) tube amp in a gig situation that I realized that power tube distortion was what I had been looking for all along. From my experience, preamp tube distortion is buzzy, in extremes like a "fuzz tone". Power tube distortion is throaty and grunty. There's world of difference. Now my rigs consist of a 100 watt tube head with a switchable channel with tube overdrive (Bassman 100T). It is also switchable to 25 watts, which is how I used to use it most often for small and medium rooms. Now I've added an Ampeg PF-50T 50 watt all tube head with the 115HE single 15" cab that I use for the small and medium gigs, only taking the Bassman for larger stages, which we play up to festival size. In 53 years of playing I've never been more thrilled with my sound. After all of this my personal opinion, no science just using my ears, is that 20% of the sound we like from all-tube rigs is the preamp, 80% is the power amp.
Just to clarify, when I'm talking about distortion from the tube amp I don't really mean raggedy, overdriven distortion, I'm talking about pushing the tube amp to just below the point where it begins to break up, where it begins generating a LOT of harmonics and also enters a beautiful self-compression (given that it's a good design) that tends to highlight the bass in the overall mix with kind of a 'halo' effect from the harmonics, and allowing the bass to sit comfortably in the mix due to the self compression. My preference for low-powered tube amps comes from being able to do this at reasonable volumes.

 

[Passinwind]

I've seen people saying the preamp tubes is all that matters to them, so i'd like to know some opinions about it

Edit: I'm seeking opinions from those who think tube amps sound better already, to know what they are talking about when they say tubes are better. Not bashing solid state in any way

Thanks for that edit. For context, I've been working on tube gear for around 50 years, but much more on the guitar side than on bass amps.

From my perspective, everything in MI amplification is a series of tradeoffs and compromises. I can and have made tube bass preamps that are pretty danged "gooey and 3-D", but the parts alone cost over a grand and the preamps take up 2 or 3 rack units. And they don't overdrive much at all unless you push the front end with a pedal or a crazy hot bass, neither of which sound all that great to me. I have another one that drives like crazy, but the noise floor is not too impressive. Then I built another one that is pretty good at everything, but not really great at anything.

Same idea for power sections. Do we need to sit in the mix or is solo clarity (or the opposite) job one?

A few designs over the years have flipped the script and used solid state front ends into a tube power section. The relative lack of acceptance of that approach just might tell us something IMHO. And of course that makes me want to roll my own that way, because Contrarians 'R Us.

 

[BassmanPaul]

Yeah, but I didn't start tormenting you all until Dec 2011. The reason I finally created a profile is tangentially relevant. I had recently bought my first all-tube bass amp since I sold my MTI SVT in 1989. The new-to-me amp was Pyrexian's old Trace Elliot V8 and it had broken down. @BassmanPaul gave me some good advice...and I get the impression he doesn't even like tube amps anymore.

Thank you for your kind comments, I’m glad I was able to help.

I still love all tube amps, it’s simply I have no use for them. I lived trough the time when to get loud enough at a gig required enduring never ending distortion. When I went to school tubes were still current technology and were part of the curriculum. As a new engineer I searched for ways to get rid of the distortion. Switching to a SS power amp I designed was a way to do that.

I should add that I love my B15N practice amp. LOL

 

[Pilgrim]

OK, having been a wet blanket, I'll offer a more meaningful response.

I've never worked with an amp that wouldn't product a sound I liked.

Blackface Bassman? Sounds good.

Hartke 100 watt head? Nice.

Sunn Coliseum-300? Super.

Fender Rumble 100? Love it!

Fennder Bassman 120 combo? Great amp.

Genz-Benz Shuttle 6.2? Faaaabulous!

Therefore, I'm agnostic. I really don't care whether an amp has tubes or not, because I know I can get a sound I'll like anyway. But the only amps that leave my house are the lightweight ones. Weight is a critical consideration for me, and that means the solid state and Class D amps are my favorites. I still have a nice blackface Bassman, but it's only used at home for practice. It's plenty loud enough for many of the gigs I play, but too heavy to lug around.

 

[Mark Reccord]

Thanks for that edit. For context, I've been working on tube gear for around 50 years, but much more on the guitar side than on bass amps.

From my perspective, everything in MI amplification engineering is a series of tradeoffs and compromises. I can and have made tube bass preamps that are pretty danged "gooey and 3-D", but the parts alone cost over a grand and the preamps take up 2 or 3 rack units. And they don't overdrive much at all unless you push the front end with a pedal or a crazy hot bass, neither of which sound all that great to me. I have another one that drives like crazy, but the noise floor is not too impressive. Then I built another one that is pretty good at everything, but not really great at anything.

Same idea for power sections. Do we need to sit in the mix or is solo clarity (or the opposite) job one?

A few designs over the years have flipped the script and used solid state front ends into a tube power section. The relative of acceptance of that approach just might tell us something IMHO. And of course that makes me want to roll my own that way, because Contrarians 'R Us.

FTFY.

But yeah, all amp design is figuring out which compromises you can live with that suit your design intentions. I'm hitting it in the preamp design I've been working on. It has to fit into a pedal so two 12A_7 envelopes is all I can fit in there but I also want a a James tone stack and active mid with switchable frequencies, which makes it really difficult to get enough gain for good overdrive. Sounds freaking deluxe clean, though, so I may not bother with tweaking the OD sounds in this one. I could get better OD with an FMV tone stack or another tube but I'm constrained by physical package size and I'm not a big fan of the FMV EQ for bass preamps.

I do think that even big push-pull tube power sections impart something to the sound that you don't get with any SS topology, even when mostly clean and they definitely go into overdrive differently. It's why I still use an old SVT. I haven't encountered any other amp that does that thing better than the SVT does for my tastes. It's a function of the whole package but the power amp is definitely a part of it.

 

[Passinwind]

I do think that even big push-pull tube power sections impart something to the sound that you don't get with any SS topology, even when mostly clean and they definitely go into overdrive differently. It's why I still use an old SVT. I haven't encountered any other amp that does that thing better than the SVT does for my tastes. It's a function of the whole package but the power amp is definitely a part of it.

Yep, I agree. Especially, since as I mentioned, I've worked on a metric shipload of all tube guitar amps, and I do still greatly prefer them for my own guitar playing. Right now I'm working up a rig for my new slide bass and I fully expect a tube power section to be in the mix. How big and how much of the frequency range it covers is undefined, but I have a range of power amp boards from 8 to 100 watts to play with for starters. And I could use a pair of the 100 watters if anyone is crazy enough to give me a gig...

 

[tekhedd]

BBut for me, the draw was the clean sound. Just sounded better to me than any SS amp whether I run them clean or dirty.

And what is "clean" anyway? "Harmonic distortion" doesn't have to mean "square wave." Tube amps add interesting harmonic distortion long before it sounds like a square wave, and subtly bend the transient attacks into fun shapes.

They also react in a nonlinear fashion, which is why a lot of good, inexpensive amp modelers sound good when messing around but fall down in real life.

 

[beans-on-toast]

You really need a tube amp to do this right. Fender Super Reverb. Joel Gottschalk on bass uses Ampeg.

 

[Wasnex]

Counterintuitive? Not at all. My approach to a tube amp is the same as my approach to an acoustic instrument. Past a certain volume level the nuance and subtlety that attracted me starts to drop off steeply.

I see...you seem to be inferring you like your tube amps clean. If this is the case, I think we are up to five who have that preference .

 

[PrinceByTor]

I went straight from a solid state to an all tube, so I might not be the best for this discussion since I never have owned a hybrid amp, but I will say the minute I turned on my SVT-VR it was one of those "That's it!" moments. Nothing beats that low-end grunt and full range of sound you get from that amp compared to my old solid state amp. I too am one that keeps my tube amp sound fairly clean; it's just more my sound.

 

[PaulCISSA]

No carrots polling option - I refuse to play.

 

[JimmyM]

And what is "clean" anyway? "Harmonic distortion" doesn't have to mean "square wave." Tube amps add interesting harmonic distortion long before it sounds like a square wave, and subtly bend the transient attacks into fun shapes.

They also react in a nonlinear fashion, which is why a lot of good, inexpensive amp modelers sound good when messing around but fall down in real life.

OK...I can accept that. Still sounds clean to me, and that's all I care

 

[Jeff Bonny]

I see...you seem to be inferring you like your tube amps clean. If this is the case, I think we are up to five who have that preference .

Clean but running the power section hard enough that I can push it into a smidge of distortion with my hands. Big distortion doesn't work for me with the acoustic instruments I'm using a lot lately. But neither does a ton of headroom.

 

[JimmyM]

I see...you seem to be inferring you like your tube amps clean. If this is the case, I think we are up to five who have that preference .

Now multiply that by thousands

 

[spiritbass]

Tube aficionados tend to prefer traditional speakers like 810s or 215s that do not have tweeters. Many of these traditional speakers roll of high frequencies, so you get a nice warm tone even if the amp is voiced rather brightly. Play a Hiwatt through a nice full range flat response cab and you'll get the idea very quickly about how bright the amps are voiced. Ampegs on the other hand are relatively flat.

Very true. I noticed the voicing differences you mention while playing my Reeves vs. my Shaw B-150 (high-powered B-15) through my MAS (full range!) cabs. I happen to like a brighter tonal palette than most, I think.

 

[Warwick Qc418]

Worth it if you don't do gigs like me. I play with a band and you could say that we are audiophile so it is worth it to me. My tube amp stays in the rehearsal room which is really well treated acoustically. IMO Tube amps deliver low end effortlessly and I love to have some preamp and power amp grit in my sound. There is nothing like it.

 

[Raw N Low]

BZZZZZZZZZZT!!!

Absolutely there are some who love that sound of a good tube output section revving it up at that crossroads point. Some love to push it way past that point as well. I love that sound my own self. But for me, the draw was the clean sound. Just sounded better to me than any SS amp whether I run them clean or dirty. I think the perception that tube amp lovers only like them for the dirt aspect is something that started in the 90's with grunge and got blown out of proportion by the internet.

So very true. IMO, the same players from that era were known for not taking care of their amps.

I like a good tube amp pushed right on the edge. I also like the roundness I can get from a good tube amp. True hybrids (not a single 12ax7 in the input stage ), really get my motor running. I'm discovering that amps from that era pair really well with today's neo cab designs.

 

[The_Owl]

I chased my tail for decades trying to replicate a bass sound I was hearing in recordings and in my head by using all mannerr of preamps and overdrives, both tube and solid state. It wasn't until I was able to play a low-powered (100 watt) tube amp in a gig situation that I realized that power tube distortion was what I had been looking for all along. From my experience, preamp tube distortion is buzzy, in extremes like a "fuzz tone". Power tube distortion is throaty and grunty. There's world of difference. Now my rigs consist of a 100 watt tube head with a switchable channel with tube overdrive (Bassman 100T). It is also switchable to 25 watts, which is how I used to use it most often for small and medium rooms. Now I've added an Ampeg PF-50T 50 watt all tube head with the 115HE single 15" cab that I use for the small and medium gigs, only taking the Bassman for larger stages, which we play up to festival size. In 53 years of playing I've never been more thrilled with my sound. After all of this my personal opinion, no science just using my ears, is that 20% of the sound we like from all-tube rigs is the preamp, 80% is the power amp.
Just to clarify, when I'm talking about distortion from the tube amp I don't really mean raggedy, overdriven distortion, I'm talking about pushing the tube amp to just below the point where it begins to break up, where it begins generating a LOT of harmonics and also enters a beautiful self-compression (given that it's a good design) that tends to highlight the bass in the overall mix with kind of a 'halo' effect from the harmonics, and allowing the bass to sit comfortably in the mix due to the self compression. My preference for low-powered tube amps comes from being able to do this at reasonable volumes.

This is exactly how I feel, as a newly converted tube amp addict. Although my journey was shorter than yours, I came to the exact same sentiment after 20+ years of playing, trying to make pedals work for me and the like. In the end, all I needed to be happy with my tone was a big, powerful all tube amp (Sunn 300T). That breakup and added harmonic content the tubes add to the sound is addictive once you've heard it.

I've had everything from Class D (Tone Hammer and TecAmp Puma), via hybrids (Trace V-type and Aguilar DB 751), to finally arrive at the Sunn 300T. They were all fantastic amps in their own right, no doubt. I used the Tone Hammer for seven years as my main and only amp. But the realisation that I wanted an all tube amp didn't come until I started dabbling in drive pedals, trying to find the perfect amount of dirt to the sound (I like a very, very subtle amount of dirt to the tone).

 

[Raw N Low]

This is exactly how I feel, as a newly converted tube amp addict. Although my journey was shorter than yours, I came to the exact same sentiment after 20+ years of playing, trying to make pedals work for me and the like. In the end, all I needed to be happy with my tone was a big, powerful all tube amp (Sunn 300T). That breakup and added harmonic content the tubes add to the sound is addictive once you've heard it.

I've had everything from Class D (Tone Hammer and TecAmp Puma), via hybrids (Trace V-type and Aguilar DB 751), to finally arrive at the Sunn 300T. They were all fantastic amps in their own right, no doubt. I used the Tone Hammer for seven years as my main and only amp. But the realisation that I wanted an all tube amp didn't come until I started dabbling in drive pedals, trying to find the perfect amount of dirt to the sound (I like a very, very subtle amount of dirt to the tone).

I know the feeling. I have its cousin the Fender Bassman 300 Pro and the mixture of channel two is unlike any other. It provides a crunch and distortion to a full body bass tone. Only other amps that can do that as whole are usually Ampegs.

Speaking of which I noticed that not every tube amp behaves like a rebel waiting to ditch private school. Some tube amps can be very warm and mild-mannered. A good distortion, drive, fuzz pedal is always good to keep in the toolbox, but nothing beats the simplicity of natural tube gain and breakup.

Edit: slight changes.