Speakers for Tube Amps.

[Sea Chief]

Is there any way I can stop this cascading headline of replies at top of page, and just have one reply below another like any other forum? it seems Ive missed a good few replies by the good folks trying to help me understand all this. Thanks to you all btw.

Actually the guy wasnt even a neighbour, he was in a house 3 or 4 detatched properties way away Id say maybe 400yds. Not a small room a large room (typical say of a US garage size). If anyones seen J Mascis play, I was reminded of that feeling so wretched loud it was: most unpleasant in fact, I was so curious to hear the amp finally 'up loud' so I thought tentatively play a few quick chords see how it sounds and turn down: before I had even stated it seemed 'bang bang bang' on the door 'EXCUSE ME- DO YOU MIND!!' etc etc etc. Ive never used the amp really since- completely impractically loud.

If I could somehow get it useable/ the volume down by way of a different speaker you see.. but still I do not understand speaker basics, if indeed there are any basic rules at all? surely there must be other than higher sensitivity = louder. Surely.

Will a bigger speaker = louder too? Does wattage have any bearing on either loudness, or break-up early or late? does a ceramic or a alnico have any similar bearing on break-up characteristics?

If I can get some order here, I can surely find a solution of sorts to my OTT volume problem.

[Steve Conner]

Just underneath the thread title at the top of the page, you should find a little menu bar. Go to the Display menu and select "Switch to linear mode".

Rules of thumb with speakers:
More efficient means louder for a given power input
Bigger ones are more efficient (more surface area to move air)
Higher wattage ones are less efficient (voice coil assembly must be larger and heavier to spread the heat, cone must be thicker to withstand the extra mechanical forces without breaking up, both mean more dead weight for the audio signal to shove around instead of doing useful work moving air)

All other things equal, the stronger the magnetic field, the more efficient the speaker will be. Ceramic magnets are stronger than Alnico, and the bigger and heavier the magnet, the stronger it will be.

Hi-fi speakers are less efficient than PA speakers which are less efficient than guitar speakers (with some exceptions)

The reason is that the speaker manufacturer measures efficiency at whichever frequency the speaker resonates and makes the most noise, so he can get the biggest number for marketing purposes. Hi-fi speakers are designed to reproduce all frequencies with even loudness, so they have to damp the resonances. PA speakers are the same to a lesser extent.

Going down this road, you would choose a small hi-fi woofer with a high power rating to allow you to crank your amp up without being deafened.

The least efficient speaker I ever tried that still sounded reasonable on guitar was an Eminence Beta 8. Small 8" cone, high power rating (IIRC Eminence claim 225W!) and designed for PA, not guitar, so it ticks many of the low efficiency boxes, but not all of them as it has a big hefty ceramic magnet.

It was still quite loud driven by a 3W valve amp. With 40W it was loud enough to gig.

[bob p]

A tweed deluxe that's being driven into "the zone" can be insanely loud... much louder than you might think.

I remember the first time that I found a real 5d3 in a music store, and the store owner let me have some fun with it because I had been a good customer for him.

The combination of an LP and that little amp cranked into the sweet spot was FABULOUS! It was so damned loud that everyone in the store stopped what they were doing to come see what was happening. Nobody could believe that that little amp could produce so much volume. The volume was so loud the owner couldn't even talk on the store's telephone. He had to ask customers to call him back. He ended up asking us to take the amp off of the showroom floor and play with it in the stockroom in the back of the store, because we were interrupting his ability to conduct business.

It was a great little amp. Being intolerably loud when you crank it? That's normal.

[Steve Conner]

I think we agree that this is normal, the question is what to do about it if it happens to be too loud for your taste. Not everyone likes rock and roll volume levels or the hearing damage that will eventually come with them.

The usual solutions are to buy or build an attenuator, fit a post-PI master volume, or just get a smaller amp. The Fender Champion 600 and Greta spring to mind.

[bob p]

because this is a site that started off as a tube amp building site (back in the ampage days), we're all still pretty biased toward the idea of getting real tube distortion, by using exotic methods like attenuators, isolation boxes, mini-watt amps, or even earplugs.

lest we forget, there's another solution that's so simple that being amp builders we like to not think about it: for low volume sometimes it makes sense to buy a nice sounding stompbox or two.

[Sea Chief]

Steve (and all here) thanks for that explanation. S'how having the words hi-fi in here calms me down so this pesky speaker info goes in my noggin a bit more easily! (a passion like GTR as you by all accounts, naim/lp12 is my thing/ diy psu etc).

Ok so its possible my brain-insane 5e3 volume was appropriately loud (although could it have been i wonder that my tubes were biased too cold, so I had to really stretch to find the start of that sweet-spot ie at very very high volume-?).

The point behind my enquiries here really is twofold: I have a sweet-looking diddy 5W 'tweed' head I built, & although the Xfmr puts out under-par on the voltage side of things (a freebie I made the amp around/ best use for it) it sounds quite good and if I turn it full and plug in the only spkr I have to hand (a 12" Peavey Bandit's Scorpion 150w approx/ 99db) it just gets some natural amp break-up.. but not much SO I was wondering if an 8" as-low-W-as-poss might be the answer to get some more 'sweet-spot' sound. But now Im muddled as to whwether this is a plan or not.

Also and more fundamentally as I dont on the whole like the 'diddy-woody-widdly' sound of a Champion (even a Champ tbh) as to me they sound a bit 'toy-shop' for a nice handmade gibson to be heard through imo, I was considering another build. This time interesting clean-tones not thick-soupy 5e3 muddy-cleans and --IF I can possibly manage to choose a speaker to fit my bill after all this consideration and brainache-- maybe just maybe I could get to some break-up tone or at least some nice almost-there/ on the edge tones (without blowing the cat up).. of an AB763 Deluxe Reverb build.

Thats the plan/ prep here you see.