Thank you, tried EFX return but get a fairly loud hum even before touching either devices volume. Headphone out was fine. Tried connecting to the input jack on my Rumble 25 (cheaper to replace), same hum. Any idea what would cause that hum? Maybe it needs a new tube, or maybe I just bought a 30 year old headphone amp.
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Thank you, tried EFX return but get a fairly loud hum even before touching either devices volume. Headphone out was fine. Tried connecting to the input jack on my Rumble 25 (cheaper to replace), same hum. Any idea what would cause that hum? Maybe it needs a new tube, or maybe I just bought a 30 year old headphone amp.
Ground loop? Use a direct box with a ground lift between them. And keep the volumes DOWN.
Thanks G-Dog. So if you have two inputs on the speaker cab, you can use one to connect to the amp head and the other to feed another cab?
If That is correct, the Ohms for two 8ohm cabs connected in this way would be 16 and not 4? Just tell me to "shut up" if I am going down a rabbit hole you don't want to get into.
Heavens to mergatrod! Blow the dang thing up a!ready would ya. 
JK.....
JK.....
Heavens to mergatrod! Blow the dang thing up a!ready would ya.
Are you talking to me? If so, I am just reacting to that screenshot that was shared. Looks like in the Rumble user guide it touches on various ways to connect multiple cabs.
That's correct, tony! Those speaker jacks on cabs are connected to each other and act as both input (from the amp) and output (to another cab)!
Most pairs, or trios, of speaker jacks are connected in parallel, and often say "Parallel Iputs" near them. And two 8 ohm cabs, connected in parallel this way, present a 4 ohm load to the amp. And, as luck would have it, many amp heads often have two speaker outputs and say "4 Ohm Minimum" near them (often with a wattage rating that the cab(s) should be able to handle). While many combo amps have only a single speaker output that says "8 Ohm Minimum", with a wattage rating, because the internal speaker(s) already present an 8 ohm load that will contribute to a total 4 ohm load when another 8 ohm cab is connected. Parallel connections reduce impedance which then draws more power from the amp. Like the Rumble 500 is just 350 watts with only its internal 8 ohm speakers, but is 500 watts with an additional 8 ohm cab (giving total 4 ohm load). More speakers and more power is what we usually want. 
Series speaker connections, where the ohms simply add to each other (8+8=16), are less common. But they sometimes have a place where you want to add more speakers, but this usually comes at the cost of reducing the power drawn from the amp! If an amp produces 350 watts with a single 8 ohm speaker load, it will probably produce only 275-ish watts with a 16 ohm series load of cabs. More speakers but less power s not usually what we want.
I hope this helps.
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Series speaker connections, where the ohms simply add to each other (8+8=16), are less common. But they sometimes have a place where you want to add more speakers, but this usually comes at the cost of reducing the power drawn from the amp! If an amp produces 350 watts with a single 8 ohm speaker load, it will probably produce only 275-ish watts with a 16 ohm series load of cabs. More speakers but less power s not usually what we want.
I hope this helps.
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American standard Jazz
Nice. I have a thing about the blackies.
For some reason I sold my Rumble 800 HD head a year ago. Very pleased and satisfied with my Mesa D800+ and subway cabs. But i still miss my Rumble from time to time. Why is that!? Lol would the Rumble head be a good match with my cabs ? (Subway 112-115, they are colorful with Mesa tone). Want to buy another one again but didnt have the chance to try one with mesa cabs. Thanks for helping me out killing the GAS, or increase it lol
Nice. I have a thing about the blackies.
What is yours?
It's a 2020 MIA Geddy Lee Jazz I have modded. Black Hipshot headstock hardware, black PG, stack knobs on black control plate, black screws. Trying to decide on Gotoh or Hipshot black bridge.
I put the black Gotoh on my single cutaway JB I built last year. Love the look. Very stable.
Thanks. The Hipshot is way more expensive and the saddles are not black is why I was looking at the Gotoh. You convinced me.
I looked at it again this morning and RTFM. I had been connecting via the unbalanced pre-amp out, and after reading, I tried it via the pre-master line out. Hum gone, Rumbles are fine. Some scratchy pots on the SWR GP, but otherwise it seems fine. Thank you everyone for suggestions and cautions.
Ahahaha, mon ami! Occasionally someone thinks maybe to leave The Club but, haw haw haw, The Club does not leave them! You are still Rumbler #1206, my beauty. 
Le Rumblé gets into your soul, cher.I do not know your cabs. But I know the soul of Rumbling! The answer is emphatically "Yes!", it can be a good match, if you use it wisely.
Point of order. We neither promote nor discourage GAS here. The Rumbles themselves promote it, and their unwise use discourages it. We can-can only empathize or assist in regaining "The Path".
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I do not know your cabs. But I know the soul of Rumbling! The answer is emphatically "Yes!", it can be a good match, if you use it wisely.
Point of order. We neither promote nor discourage GAS here. The Rumbles themselves promote it, and their unwise use discourages it. We can-can only empathize or assist in regaining "The Path".
.
When I down sized for the final time, I'm glad I went back to the Rumble 100. Great tones, and just the right amount of power for my needs. I've always liked 12" speakers since 1968.
Thanks for that testimonial, our once & forever Rumbler #131!
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It's an easy testimonial, when it's the truth about the Rumble Series. RUMBLE ON!
