Tube Amps versus Solid State

So…this isn’t so much a diatribe against or for anything, but recently I’ve come into possession of a Blackstar HT-20 tube amp. I’ve never owned one before, always solid state prior to that.

I have a friend that STRONGLY recommended against a tube amp purchase years ago, convincing me to buy Amplitube software, studio monitors, headphones and an audio interface from Avid that included a basic version of ProTools. His logic was that for the same money, I could have a software suite that simulated a magnificent array of amps/effects/recording rooms, be able to actually record, and not wake up the neighborhood. At the time, I was considering a 5W Blackstar HT-5 halfstack. I conceded his point and bought the requisite shit and was pretty blown away.

Fast forward 8 years, and now I HAVE purchased a tube amp as mentioned above. It’s a practice/small club amp, but I have to say…good Lord, IT’S REALLY LOUD, ear piercingly so. On the gain channel I put the volume at 12 o’clock with reverb and the ISF knob towards British…it’s far, FAR louder than I believed it would be. It’s interesting to note that saturation of tubes and volume doesn’t seem to increase much if I push the master volume up all the way…just increases feedback, which I already get plenty of at twelve o’clock (half volume).

In fact, we had some nice weather here recently and I had all my windows open and it drew the attention of neighbors and the police! I knew it was earsplittingly loud close to me but didn’t consider it carrying all over the neighborhood. The cop was yelling through my front window and I only heard him during a pause in my playing as he was SHOUTING through the front window…he told me he’d been trying to get my attention for almost 30 minutes! So…the question becomes: why are tube amps LOUDER than their solid state counterparts, and is that trend changing?

Well, obviously you need to keep the windows closed or get cooler neighbors.

Fact is, tubes and transistors put out largely the same volume. But was the combo that attracted the neighbors a Blackstar HT-5? They can get loud-ish, but they’re not drum set loud.

There are a few reasons but two of the main ones are:

Typically you drive tube amps to breakup in order to gain the characteristic sound and with solid state amps you avoid breakup due to the hard clipping.

This effect also leads to a perceptual increase in volume as clipping starts as the harmonics produced by tube breakup sound louder to the human ear compared to the clipping effects of solid state amps…

No, it was and is a 20-watt Blackstar HT-20 combo amp with a 12" speaker. I’m sure it helped that I replaced the stock Rocket 50 12" with a Celestion 12" Vintage early in the game. I just need to remember how much louder this thing is and respect my neighbors. I’m getting ready to move into an apartment. I cannot imagine what they’ll think of me. There’s no headphone jack and being a tube amp, I need a certain level of volume to just get the sound.

Maybe so, but this amp is an order of magnitude louder than my previous 20-watt Fender Champ, and it’s not even close. My friend was right: I am an annoying prick to my neighbors if the windows are open, even if I’m good. Most people just don’t want to hear it. I’m continually amazed at the volume of this thing. It’s so much louder than I thought it would be. Credit my friend for being right, but goddammit…that sweet, sweet sound…cannot be replicated by an SS amp.

it’s all in your head, man. 20 watts is 20 watts, all else equal. if you’re talking about the difference of the sound when you’re overdriving them, that’s one thing.

That’s not really true, is it? I mean, I can sit in front of my little 20-watt Fender solid state amp, crank it all the way and it just increasingly more and more sounds like dogshit.

This Blackstar amp though…when I sit near it and it’s at full gain, mostly British tone on the ISF knob and 3/4 reverb makes my ears ring when I’m near it. It’s CERTAINLY louder than the other similarly rated SS amp. It’s like night and day and this is at HALF master volume. It’s not close. Hence, cops.

Loudness is a very difficult thing.

Your ear perceives loudness in a manner quite different to a sound meter. (Anyone wanting to ground truth tube versus transistor amp loudness has to use a meter before they start arguing.)

Your ear will distort when the sound pressure gets loud. Never a nice feeling, but your ear will cheerfully clip, and even before this, loud sounds start distorting significantly. So your brain will start perceiving sound that sounds like your ear being driven into distortion as very loud. Crank a tube amp and you seem to start hitting those same sounds.

Also, power ratings of amplifiers is not a simple figure of merit. Especially not when guitar amps are concerned.
If you have a hifi amplifier - one that won’t be driven to clipping at all, you can work out a useful peak power rating by measuring the power rails and the impedance of the speaker and applying P = V[sup]2[/sup]R. RMS is that times 0.707. But this doesn’t take into account all sorts of issues, especially inherent current limiting in the power supply and thermal limits on delivering that power. If you are allowed to clip the amp its power is not derated by 0.707. But this is really all noise compared to the real deal.

Clipping the amp places almost arbitrary amounts of energy into the distortion harmonics. That is what makes it loud.
And that loudness isn’t all about distortion products from the preamp. Proper tube guitar amps are a real mess when it comes to the power stage. Mess in a good way. I notice the Blackstar HT-5 uses a pair of 12BH7 tubes as the output stage. Lordy, that is slamming those hard. That amp is designed from the ground up to provide serious power amp distortion. A triode won’t get you the quite sound of a pentode overloading, although there are few tricks that can approximate it. (Pentodes have a characteristic knee in the transfer function that provides that crunch.)

So you have an amp that is designed from the ground up to give power amp distortion at low levels. Yes, it is going to sound seriously loud.

As a counterpoint, listening to high end HiFi is revealing. You can turn up the levels to the point your ears ring, but it never sound really loud. Not in the way a tube guitar amp can.

Yeah, this is where my complete ignorance in electronics is no help. But yeah 20w is more than loud enough to get over drums.

If you were playing that loudly and obliviously that it took the cops 30 flippin minutes to get your attention, well, whoa. I hope you wear earplugs. I would also suggest you shut your windows. I live for good loud guitar, but I don’t torture my neighbors. The other day I grooved on an Open G version of Trampled Under Foot, setting up a drone string and choogling along for, I dunno, 20 minutes or so. Let’s be clear: I sounded glorious ;). But if I had an open window, I suspect a brick would’ve come through it before I had finished.

I didn’t mean to be a dick…I was in a room in the back of the house facing the woods, it was later at night, and I just basically forgot about the open windows as the weather had been so mild recently. The police officer was nice, even complimented me on my playing, but he had a job to do and I was pretty sheepish about the whole affair.

I don’t think it helped that I was also playing along to my computer on Youtube, my PC has a 10" subwoofer and five satellite speakers and in itself is fairly loud. Of course I had to crank that up all the way just to hear it over the amp. Lesson learned…my amp with the Celestion VC-30 in it is LOUD for home practice.

It is capable of being played at lower volumes, though, despite not having a headphone output. It just doesn’t sound as good.

One of the things I am trying to understand is the master volume. On the clean side, volume steadily increases all the way up to the limit without any feedback. On the gain channel though, half volume will produce nearly constant feedback unless you “palm” the strings, and the volume itself doesn’t seem to increase any from that point all the way up to 11. Why is that?

I have a Blackstar HT-20 combo, not an HT-5, which uses 2 EL-34 tubes and two 12AX7 tubes. I have replaced the original Rocket 50 speaker with a Celestion V-30 Vintage, and it makes a huge difference in the sound and overall output (to my ear anyway).

The Master Volume sets overall loudness. Other Volume and Gain knobs on that channel affect the sound, but the MV sets overall. However, if you dial up the other knobs too high, then raising the MV can get the signal to howl, especially if you also have pedals or are playing through a feedback-leaning guitar.

Have you checked YouTube for demo vids for that specific model where people dial up a tone you like? Do that.

Yep, even if the nominal impedance of both speakers is the same (e.g. 8 ohms - a reasonable assumption in this case, as there’s no 4 ohm version of a V-30), you’re still seeing a difference in the sensitivity of the two speakers.

Celestion rates the Rocket 50 at a sensitivity of 95 db (1 watt/meter, presumably), while the V-30 gets rated at 100 db. Assuming these numbers are accurate, a 5 db difference in speaker sensitivity means that your 20 watt amp is now approaching the sound levels you’d get from an 80 watt amp (you need to double your amplifier power to net a 3 db increase in sound pressure level).

You may want to drape a few layers of carpeting over that amp when you turn up. :slight_smile:

Haha! Thanks for that description.

I had an over-the-top 180W Fender Super Twin. Bought it when I was 18 and thought “the bigger the better”. I sold it maybe two years ago and went complete opposite: Yamaha THR10. Very small and doesn’t get loud (I think it has like a pair of 3" speakers). But it sounds pretty great at low volumes and does a pretty good imitation of a clean to crunchy Fender, an AC30, a Plexi, a JMP800 and a dual rectifier. It has some good sounding built-in effects.

Now, I’m wanting to add a small tube-amp. Something that can sound decent without having to be cranked and will work well with pedals. I guess I can cross the HT-20 off the list. :smiley:

Anybody have any experience with load boxes? I’m curious about them but I admit having no experience with any.

I have a Fender Blues Jr amp that gets too loud for my practice room when I try to push up some tone on it. I’m thinking about trying one of these boxes.

I’ve seen them advertised in Sweetwater catalogs. If you have a separate speaker cabinet they insert into the chain between the amp and the speaker cabinet. For a combo amp you’d have to do a little rewiring by disconnecting your speaker leads and then wiring the box input/output between them.

The device supposedly keeps your tube tone intact while attenuating the speakers to a lower volume (some models even have a headphone out).

Pros - keep the police away
neighbors don’t pick up axe handles and pitchforks
You get that sweet tone while saving your eardrums

Cons - Cost ($100 - $1000)
Combo Amp would require some re-wiring

Feedback requires a certain amount of volume, but actually surprisingly little*. What it does need is gain.
An overdriven tone means you can have a lot of gain without necessarily a lot of volume – hence the feedback.
A clean tone with a lot of gain = rattling the windows and shaking stuff of the shelves.

As to the valve vs transistor volume issue, I’ll just add that any overdriven amp will be loud, but an overdriven transistor amp sounds awful, overdriven valves do not.

  • The strings just need to be able to ‘hear’ the output

It’s actually a super sweet amp, but geared a little more towards hard rock and metal than any Fender rig is going to be. And I can play it at lower volumes on the gain side and get decent saturation. One extremely important control that I need to fiddle with more is…the volume knob on the guitar itself!

And wordman, I will check that out. The Schecter C-1 Classic I’m playing through has a pretty hot humbucker in the bridge, so maybe that accounts for some of the feedback as well.

I have a Tele with single-coils, a Hondo flying-V with humbuckers and a Harmony Rocket semi-hollow body with gold-foils. I can’t get that Harmony within 100’ of a turned-up amp. It can even feedback with the little practice amp. I sold the Fender Super Twin before I got the Tele so I can’t really say how it handles a loud amp. My Hondo was controllable with the Super Twin up to a certain point (that thing was extremely loud).

I have a C-1 Elite; it’s the best guitar I own that cost me under $1000. Love that thing.

Been interesting reading this thread. I have many amps, both tube and trans, and love them all. And yeah, the tube amps all seem louder than a corresponding solid state amp. I play with lots of gain, so every new amp is a challenge to find that sweet spot where it’s loud enough to rip my scalp off but not so loud as to annoy the shit outta my neighbors.

Most of my Volume knobs never make it past 2.

Link to a years-old thread on tube vs solid state amps: Tube vs transistor amplifiers - Cafe Society - Straight Dope Message Board

Same with my Schecter. I absolutely love playing it, the sustain, the build quality and materials…all of it. A generous fellow Doper sold it to me years ago for $450 with the case.