More Model T questions

[doomfiend]

Allright, so I got my tubes sorted out due to price right now, since I need a cab as well.  My next question is:  Does the T put out more power running at different ohmages?  I think I'm gonna be running 2 4 ohm cabs so it'll be at two ohms.  Will 2 ohms effect the tone, volume, output, life of tubes?

I've just been curious.

[Isaac]

No, tube amps use transformers to match the impedance of the output tubes to the load, so they put out the same amount of power into any load, as long as the impedance selector is set properly.

[Soundmasterg]

To elaborate a little bit....

If your speaker cabinet is 8 ohms, and you plug it into the 8 ohm jack on the amp, the amp will put out its rated power, whatever that may be. If you have a 4 ohm speaker cabinet and plug that into the 4 ohm jack on the amp, it will again put out its rated power. If you plug an 8 ohm speaker into a 4 ohm jack, or plug a 4 ohm speaker into an 8 ohm jack, then the load on the amp is mismatched, and the amp will put out less power either way, with a different harmonic spectrum of sounds, and it is harder on the amp when mismatched, so the tubes work harder and can burn out quicker. In addition, some cheaper amps will use transformers that can't tolerate a mismatch like that for very long, and the transformer will not like the mismatch and blow. It is always best to get the proper load on the amp for best tone and power. Mismatching down ( 4 ohm speaker on 8 ohm jack) is harder on the amp and tubes than mismatching up, mainly because the tubes are working harder in this mode, and the output transformer can arc internally in this mode which would cause it to self-destruct.

If you're running two 4 ohm cabinets, then if you run them in parallel, they would be at two ohms, and you would want to plug into the 2 ohm jack on the Model T, if it has one. If the amp doesn't and you plug in a 2 ohm load on a 4 ohm tap, it isn't good for your amp to do that, your tube life will be shorter, you may blow things up, your tone won't be as good, and the overall volume will be lower.

So best advice is to get whatever cabinet setup will give you a load the amp can run well with an existing output jack or switch on the back of it already.

Greg

[doomfiend]

Allright, cool.  Yes, the T has a 2 ohm out, and yes, I was aware that technically speaking that I should be okay if I am running into 2 4 ohm cabs out of the back of the T at 2 ohms.  I was more wondering if there are different tonal qualities at different ohmages, as bass rigs seem to run at 4 or 2 ohms way more than guitar cabs, so I figured that there must be a reason.  I'm planning on running a 4 ohm Ear Candy Cabs BuzzBomb 2x12 and a 4 ohm Peavey Black Widow 1x18 cab

[Ryan_77uk]

The lower the ohms the more volume you get I believe. My Model T sounds a hell of a lot louder at 4 ohms than it does at 16.

[Isaac]

What do you mean by that, Ryan? Are you suing the same 4 ohm cabinet, and just changing the impedance selector? Are you using different cabinets? If so, what are the differences? Are you using more cabinets?

[Tom Loizeaux]

Tube output amplifers that use output transformers sound the same at all impedances. Matching the output impedace with your speakjer cabinet reduces the stress on the tube amp.
Solid state amps put out more power as the speaker load (resistance) decreases. Damping factor is reduced as the load decreases and amplifer overheating becomes an issue.
Combining speakers will increase your power potential and putting two drivers close together will increase the low end slightly. To get "noticeably louder", you will have to significantly increase amplifer output.

Tom

[giovanni]

The lower the ohms the more volume you get I believe. My Model T sounds a hell of a lot louder at 4 ohms than it does at 16.

unless that model t is an early solid state peavey or a car amp, this is impossible

[EdBass]

The lower the ohms the more volume you get I believe. My Model T sounds a hell of a lot louder at 4 ohms than it does at 16.

unless that model t is an early solid state peavey or a car amp, this is impossible

Brand, age or application of amp is irrelevant, tubes are tubes, and transistors are transistors. Tom Loizeaux's answer below is a succinct explanation of this, even leaving the transformerless tube amp option open as they do vary output with load; their constant dynamic output actually decreases with load, while their peak sound pressure output increases as with a solid state amp.

Tube output amplifers that use output transformers sound the same at all impedances. Matching the output impedace with your speakjer cabinet reduces the stress on the tube amp.
Solid state amps put out more power as the speaker load (resistance) decreases. Damping factor is reduced as the load decreases and amplifer overheating becomes an issue.
Combining speakers will increase your power potential and putting two drivers close together will increase the low end slightly. To get "noticeably louder", you will have to significantly increase amplifer output.