I get a little frustrated when I’m watching YouTube guitar channels and they’ve got this big ass shelving unit with a bunch of individual 100 watt tube heads from various companies.  Do you know when you need a 100 watt tube amp? You need one when you want to impress people on YouTube or when you’re a tone snob.  Other than those two reasons, they don’t make sense.  So how many watts do you REALLY need?

For the sake of argument, we’re limiting ourselves to tube amps here.  This is an academic exercise. Let’s go small through huge venues and see what makes the most sense.

Disclaimer – I think 4-12 cabs are amazing.  They sound great.  If you have the room for them, they’re awesome.  I wouldn’t want to gig with one unless I didn’t have to carry it, but it’s a big speaker cabinet and it sounds big.  I don’t have any issue with big cabinets.  We’re talking about tube amps here.

Bedroom

You’re jamming in your bedroom, maybe alone to backing tracks, maybe you’re recording, maybe you’re doing the guitarist thing and noodling aimlessly.  There are other people in the house and you’re likely to be playing at conversation volume.  For this use case, if we’re talking tubes, a 1 watt amp is great.  Lots of smaller amps allow you to dial down the power – my Peavey ValveKing 20MH can dial in 20 watts, 5 watts, or 1 watt.  At 20 watts, both output tubes are used.  At 5 watts, only part of one of the output tubes is used.  And at 1 watt, the signal is routed very close to an output tube, but not actually through it.  I may have made that up.  Most 15 to 20 watt tube amps work fine in a bedroom because they have a master volume.  In some cases, you can even use a 40 watt tube amp (Marshall DSL 40) and in some cases you can’t (the notorious Fender Hot Rod Deluxe, which goes from whisper to WAY TOO LOUD between 0 and 1.)

Small Gig/Recording Studio

To keep up with a real live drummer, depending on the music, it’s pretty standard to use a 15 or 20 watt amp.  In some cases you can use a 30 watt amp, but that might end up being too loud.  The exception is when you need a really loud clean tone, in which case 30 to 50 watts works very well.  Some people roll up with a 12 watt Fender and dime it and it sounds great (although not exactly “clean.”)

If you show up to a small gig or studio with a 100 watt head, people will glare at you.  One could make the argument that a 100 watt Marshall sounds different than a 50 watt Marshall, because it does.  But there are sooooo many lower wattage amps (both old and new) that sound amazing, and some studios aren’t really prepared for all 100 watts of that Marshall.  It’s overkill.  Still, some will insist on bringing their 100 watt head and 4-12 cab and creating a sound louder than a jet engine, capable of damaging your hearing.  This does not make much sense to me.

Big Gig

For something like a 28,000 seat outdoor theater, aka the best sounding venue, does that 100 watt head make more sense?  Well… I still say no.  Modern PA systems sound amazing and the tech they use is also amazing.  They use multiple speaker arrays so that each area of the venue is covered well.  Arrays allow the sound engineers to aim individual speakers at specific sections of seats.  If they mic up your amp or use some type of load box and IR, they’re going to have a lot of control over what the guitar sounds like.  If you’re cranking out 100 watts on the stage, they can still mic your amp or use an IR, but what’s coming from the PA will have to fight with what’s coming from your onstage stack.  You can get all kinds of comb filtering and other issues.  Bands like Metallica use digital amp modeling to get the best possible guitar sounds in a live setting.  Rush was using IR files for years before they stopped touring.

The best case for a 100 watt tube amp is to have a vintage 100 watt tube amp that sounds amazing.  And even then you might want to consider a load box/IR approach to avoid becoming one with the jet engine.

Bathroom

In my bathroom I’ve got a copy of the latest Sam Ash catalog next to the toilet to keep me occupied.  You know what never appears in those catalogs?  100 watt half stacks.  That’s because the only people who buy new 100 watt tube amps are the people who want to impress other people.

The right tool for the job.  Do you really want to drive a school bus to the grocery store?