head tone vs cab tone

[leftylover]

how much of the tone comes from the head, and you much from the cab/speakers?

[Splattle101]

It depends…on everything. Of course. It’s to do with guitar, so what else would you expect?

First, the cab type. Open are more immediate sounding, and feel more articulate at lower volumes. They seem to fill a room, too, in all directions. Closed cabs project in the direction they’re pointing and can be a bit thin at low volumes. At high volumes they retain their bass far better than open cabs.

Then there’s the drivers themselves. If the power of the amp is half the power of the speaker, they’re what I would called well-matched for power handling. If they’re well matched, then you’ll get a reasonable compromise between articulation and distortion. Articulation, and the ability to reproduce really high frequencies associated with fret and pick noise, requires headroom. But the speaker colours the tone quite a bit, and if you want to hear that colouring, you need to drive the speaker until its distortions become audible. (By ‘distortion’ I mean any change to the input, not just what we guitarists think of as distortion, ala stomp box. Distortion in the audio engineering sense means anything at all from full bore clipping to adding subtle extra harmonics.)

If your speakers are not powerful enough to handle the amp, you’ll hear the voicing of the speaker (i.e., it will colour the sound), but you’ll lose articulation and transients. If your speakers are too powerful for the amp, you’ll never hear their voicing. If they’re really too powerful, they’ll sound dead and you’ll loose articulation because the amp doesn’t have enough grunt to move the coil properly against the resistance of the suspension (and the air behind the driver, if it’s a closed cabinet).

Hard rock and metal players tend to go for overpowered speakers to retain their attack and tone at high volume when playing at high speed. Pure blues aficionados tend toward underpowered speakers so you can hear the driver protesting.

Then there’s the particular voicing of a particular driver. Celestion is the benchmark for the ‘Brit’ voicing, which can be thought of as aggressive and in your face, courtesy of the full high mid response. American voiced speakers (like old Jensens) are fuller in the bass, and brighter in the treble. This is, of course, a vast oversimplification, but it gives you a general idea.

Then there’s the amp. If you run your 100 W valve head at 40% power through a 4x12 loaded with 25 W speakers, your tone will be determined pretty equally by head and cab. If you like to turn your 100 W head to 60% or higher, your speakers will become a larger part of your tone, ala classic blues and rock.

If you run a 50 W head through the same cab (i.e. well matched) and you run it at 60% power, you’re going to hear the voice of your amp AND the voice of your speakers, but you’ll have enough speaker headroom left that you won’t have to wade through an ocean of speaker compression to get there.

And so on…

Changing drivers can make a huge difference to your voicing. Changing cabs, or even just ADDING a cab can do likewise. It's a complicated brew.

[boycey]

Excellent post Splattle.

[dwagar]

yeah, great explanation man.

just as with a guitar, everything to do with the amp/speakers make a difference in tone too.

[Torren61]

Great explanation. So...what about a 2 watt tube head or 5 watt tube head pushing one 12" 30 watt Celestion Gold alnico? What about pushing a preamp signal into the front end of the amp and then into the speakers? Does the speaker voice become revealed?

[hipofutura]

I have no first hand experience with the Celestion 12" Gold speaker, but I'll offer my opinion anyway. I could only find a 50W version with my web research, no 30W. The 50W speaker looks to heavy for a 5W amp. This speaker is more like a JBL D120 with a smaller VC. Even though it is a very efficient speaker, the motor and cone structure look like they would require more than 5W to be articulate. There's a lot of moving mass with that speaker. I suspect you would loose detail with the small amp. A 5W amp is better matched with a 10" speaker that has a smaller VC and lighter magnet.

[Torren61]

You are correct. It is a 50 watt speaker. My bad. It does sound very good when I use Guitar Rig 3 as a preamp and run it through the amp input and crank either the 2 watt or 5 watt head.

I actually HAVE a 10 inch JBL but I haven't built a cab yet.

[hipofutura]

If the JBL is a D110 it will be way to heavy for the 5W amp. I have a D110 (10") and a D120 (12") that are both too heavy for my 6W Ceriaton BF Vibro Champ. Which is why I used Weber Vintage Series 10" speakers for the Ceriaton. The JBLs are both exceptional speakers but they were designed to be driven by higher watt amps. I'm using the D120 in a 1x12 custom cab for my 50 Traynor tube head.

[Torren61]

Well, I'm wrong again. I went and dug it out and it is a 8" MOD series. JCH 8/35 - 8 OHM

[Splattle101]

Originally Posted by Torren61

Great explanation. So...what about a 2 watt tube head or 5 watt tube head pushing one 12" 30 watt Celestion Gold alnico? What about pushing a preamp signal into the front end of the amp and then into the speakers? Does the speaker voice become revealed?

Well this is the thing: it depends on what you want. Imagine a metal head with a 100 W head, pushing gain to hell and beyond. Imagine he's running all this through a cab with four 30 Watt Celestions. The speakers will be breaking up and colouring the sound a lot.

Now imagine he changes the 30 W speakers for 100 W Celestions. He can now hear all that fine detail that was getting compressed out by his overdriving 30s. He ist for joy jumping, ja? Well, technically, the new speakers are colouring his tone less than the old. But on the other hand, they are now contributing mightily to his new tone by letting the sound of the 100 W ear-destroyter through. They contribute to his sound by NOT colouring it. Which is what he wants.

So what's right is a question for you, personally. The constraints are really a matter of sufficient power to drive the speaker, and sufficient power handling in the speaker to take your amp. In between there is an ocean of options.

[Torren61]

I see...I think. Then even though the amps I'm using to push a 50 watt speaker are rated far less in wattage, they are indeed driving the speaker and I'm getting everything that I can get out of the heads and I'm not losing any detail.

When I run a preamp with effects into the front of my amp, if I'm losing any detail then it's going to be between the preamp and the amp and not the speaker? I'm not, but I figured I'd ask the question while I had you on the phone

Btw, I really enjoy a thread when you get involved. Your answers are thoughtful, articulate and well written.

[Splattle101]

Thank you. I enjoy the opportunity to discuss this stuff.

[jonesy]

Originally Posted by leftylover

how much of the tone comes from the head, and you much from the cab/speakers?

Splat actually already gave you a really good explanation to your question

I think of it like this, if you run a line out from your amp you hear only amp tone. If you mic up speaker (I prefer mic to line out) you are actually hearing the air moving and sound pressures created by speakers and cabinets.

The same speaker will sound different in a closed cabinet than it does in an open back cab.

I like 50 watt amps with 12" 50 watt speakers, vs 100 watt heads and 100 watt speakers. I find I can get a better Tone at lower volumes this way and it works for what I play, Blues and Classic rock.