Little Mark II SPEAKER OUT with no load?

[archeobassist]

NO, you are not understanding the important details of what I have been saying.

Load boxes are designed specifically for tube based power amps. Tube power amps can NOT be used without a load connected to the speaker output. Tube amps are also generally not bridged topology.

Your Markbass amp does not contain a tube based power amp and CAN be used without a load connected to the speaker output. Some MarkBass amps use an internally bridge mode class D power amp, so my general comment and warning is that you should NOT use this type of amp with a load box because the necessary isolation is not often included and serious damage can result to both the amp and the device that it is connected to.

Most load boxes do not mention this caution because they were never intended to be used with such amps that use bridged connections. They are also generally limited to about 100 watts maximum power.

Use the LINE output or the DI output (depending on the type of connection you need), do NOT use the speaker output for anything but a speaker.

Ok thanks, now everything is clear...Sorry if I sounded dumb af, I admit I have a lot to learn about the technical side of gear but fortunately there are sites and people like you guys, kind and patient enough to help!

 

[archeobassist]

• Tube amp: Use an appropriate load box if you're not using a speaker. Your Markbass LMII is not a tube amp.
  
• Solid state amp: Do not use a load box. You can operate the amp without anything connected to the Speaker Out. Your Markbass LMII is a solid state amp.
• Hybrid amp: This is a solid state power amplifier with a tube preamplifier. Do not use a load box. You can operate the amp without anything connected to the Speaker Out. Your Markbass LMII is not a hybrid amp.

Use either the DI out or Aux Out as appropriate when connecting to other audio interfaces, such as a mixer or analog-to-digital recording unit. Adjust input gain on the audio interface for the best signal quality.

And I really miss Roscioli's pizza and pastries! Stay safe in Rome!

Oh man, Roscioli! I'm a tour guide in Rome, that's one of the (many) places I miss, the Colosseum, the Sistine Chapel...way too many to mention all of 'em!!! If you will come back to the Eternal City when this mess will be over, it would be great to meet there!

 

[HolmeBass]

Do not do this, it's a good way to damage both the amp and what you connect it to. Especially if it's one of the newer MarkBass class D versions which operate internally in bridge mode.

Operating without a load (no connection) is not a problem though

I would follow this advice.

 

[diegom]

Using a load box on a solid state amp is useless. And good luck getting a load box that works on a 500w amp.

Just use the line out and forget the silly notion of using a load box on a solid state amp.

Just out of curiosity, do the SS Acoustic or a Sunn amplifiers sound any different when cranked, or is it just the speakers begging for mercy???

 

[abarson]

Oh man, Roscioli! I'm a tour guide in Rome, that's one of the (many) places I miss, the Colosseum, the Sistine Chapel...way too many to mention all of 'em!!! If you will come back to the Eternal City when this mess will be over, it would be great to meet there!

I'd look forward to that. We loved Italy, didn't have a single morsel that wasn't a revelation. Trattoria Massa was lots of fun. And everyone was warm, inviting and friendly!

Don't worry about sounding dumb, we all learn. Sometimes it's not easy weed through all the nonsense and myth.

 

[JimmyM]

Just out of curiosity, do the SS Acoustic or a Sunn amplifiers sound any different when cranked, or is it just the speakers begging for mercy???

You're asking me? Know how long it's been since I played either one? Not since the 70's have I done so!

 

[agedhorse]

Just out of curiosity, do the SS Acoustic or a Sunn amplifiers sound any different when cranked, or is it just the speakers begging for mercy???

Both of those amps have a different architecture than modern linear amps. The power amps may indeed clip differently, though I would expect the speaker is the larger contributor.

 

[TrevorR]

Ok thanks, now everything is clear...Sorry if I sounded dumb af, I admit I have a lot to learn about the technical side of gear but fortunately there are sites and people like you guys, kind and patient enough to help!

One other thing I don’t think anyone has mentioned... (in layman’s terms) instrument and line level circuits are designed to work with currents in the milliamperes range. Speaker outs can carry currents in the amperes range. So if you connect a speaker out to a line or instrument in you’re asking it to carry current around 100s to 1000s times greater than it was designed for. You’re pretty much guaranteed to overload and blow the preamp/amp connected to the speaker output.

Another reason why you mustn’t use a guitar cable as a speaker lead. It’s just not designed to carry that sort of current!

 

[agedhorse]

The voltage of a speaker output is over 10x the voltage of a line level signal, this is one cause for the damage.

The other cause that I mentioned that's focused around bridged amp topologies is that they are not ground referenced on the speaker output which causes other serious issues.