Mesa Subway heads - headphone out to DI?

[scooter76]

I've discovered my bass head has cab simulation via the headphone jack, but not the DI. I'm curious to hear the difference as a signal to FOH or audio interface.

However, checking the manual warns against plugging in anything but headphones.

What kind of plausible damage could occur by plugging it into a DI box? Will that much of an impedance mismatch cause problems for the headphone amp? Would passive/active help/hinder anything?

Although the manual references being able to handle 'well above 32 Ohms', I'm under the impression a DI box input is in the kOhms territory. But I'm also under the general impression that going higher than an amp's rated impedance is generally fine, sacrificing only signal level.

Pertinent manual bits below (Mesa WD-800). Thank you!

"will drive all common headphones and IEM ear pieces between 8 and 32 ohms (and many well above 32 ohms)"

"This output should not be connected to anything but headphones or ear buds."

 

[60bass]

I've discovered my bass head has cab simulation via the headphone jack, but not the DI. I'm curious to hear the difference as a signal to FOH or audio interface.

However, checking the manual warns against plugging in anything but headphones.

What kind of plausible damage could occur by plugging it into a DI box? Will that much of an impedance mismatch cause problems for the headphone amp? Would passive/active help/hinder anything?

Although the manual references being able to handle 'well above 32 Ohms', I'm under the impression a DI box input is in the kOhms territory. But I'm also under the general impression that going higher than an amp's rated impedance is generally fine, sacrificing only signal level.

Pertinent manual bits below (Mesa WD-800). Thank you!

"will drive all common headphones and IEM ear pieces between 8 and 32 ohms (and many well above 32 ohms)"

"This output should not be connected to anything but headphones or ear buds."

Andy can surely clarify this for you as he designed the amp.
@agedhorse

 

[scooter76]

Andy can surely clarify this for you as he designed the amp.
@agedhorse

Thank you, wasn't sure if mentioning worked on this forum. His ongoing support is gold, one of the reasons I went with the Mesa.

 

[60bass]

Thank you, wasn't sure if mentioning worked on this forum. His ongoing support is gold, one of the reasons I went with the Mesa.

That's one area where TB really shines. The manufacturers are also members and are usually always available and willing to help. I also own the WD-800 and it's a great head.

 

[WRM]

Here's his answer (link to post didn't work correctly)....

"No, the headphone output is for headphones and ear buds only.

The cab sim is based on headphones. Since the drivers are very close to the eardrums, and they typically have a more extended HF response than any speaker, the cab sim addresses this effect specifically,"

 

[agedhorse]

No, the headphone output’s signal is high enough that it could damage some high impedance external devices like DI’s, interfaces, etc.

The DI output also has a very mild cab emulation, more like an FRFR style cabinet similar in some ways to the Subway 115/215.

It’s different than the headphone cab sim because it’s not intended to correct for the sound source being mm away from the ear drum.

 

[scooter76]

No, the headphone output’s signal is high enough that it could damage some high impedance external devices like DI’s, interfaces, etc.

The DI output also has a very mild cab emulation, more like an FRFR style cabinet similar in some ways to the Subway 115/215.

It’s different than the headphone cab sim because it’s not intended to correct for the sound source being mm away from the ear drum.

Thanks for chiming in, appreciate it. Noting the emulation via XLR DI in a future manual revision would be handy, mentioning one but not the other is confusing. Also maybe dangerous, I have a thread elsewhere of live sound ppl repeatedly saying no problem, go for it lol. I'll set them straight, and hopefully this thread will help in the future (like all your efforts here), cheers.

 

[agedhorse]

Thanks for chiming in, appreciate it. Noting the emulation via XLR DI in a future manual revision would be handy, mentioning one but not the other is confusing. Also maybe dangerous, I have a thread elsewhere of live sound ppl repeatedly saying no problem, go for it lol. I'll set them straight, and hopefully this thread will help in the future (like all your efforts here), cheers.

The emulation on the DI is very mild, not really worth mentioning compared with the headphone output.

 

[WRM]

The emulation on the DI is very mild, not really worth mentioning compared with the headphone output.

Shouldn't take much - signal is already mostly perfect?...

 

[sawzalot]

Related question—does the Subway or Subway+ preamp have the same cab emulation?

 

[agedhorse]

Related question—does the Subway or Subway+ preamp have the same cab emulation?

Basically yes on the DI out, but there isn’t a headphone out.

 

[S-Bigbottom]

Thanks for chiming in, appreciate it. Noting the emulation via XLR DI in a future manual revision would be handy, mentioning one but not the other is confusing. Also maybe dangerous, I have a thread elsewhere of live sound ppl repeatedly saying no problem, go for it lol. I'll set them straight, and hopefully this thread will help in the future (like all your efforts here), cheers.

To effect the DI signal flip the switch in the DI section to POST EQ and turn the knobs. This is your "cab sim".
Treble all the way down equals a tweeter less cab...kind of. Bump the low mids for more "old Schoool". Adjust to your flavor.

Warning: If you make too extreme of adjustments they may not translate well to the PA, now the Sound Man only has your muffled sound to work with.

 

[beans-on-toast]

Plugins can be loaded into some FOH consoles so cab sims can be applied to your DI signal. Also easy to do with audio interfaces into DAWs. Failing that you’d want an external box that accepts the amp’s DI adds a cab simulation, then sends that out through another DI.

If you have a line output on the amp, you can a product that adds cab sims and then outputs via an XLR DI.

one such product is here:

OPUS - Amp Sim & DynIR Engine

Introducing OPUS, an end-to-end tone shaping Amp Simulator and DynIR™ Engine ushering-in the next milestone-evolution of the Two notes ecosystem.

www.two-notes.com

 

[agedhorse]

To effect the DI signal flip the switch in the DI section to POST EQ and turn the knobs. This is your "cab sim".
Treble all the way down equals a tweeter less cab...kind of. Bump the low mids for more "old Schoool". Adjust to your flavor.

Warning: If you make too extreme of adjustments they may not translate well to the PA, now the Sound Man only has your muffled sound to work with.

In post, that would be an amp sim except that it’s the real deal!

 

[tshapiro]

Just curious @agedhorse. Seems a DI like the countryman 85 which has a speaker input mode with 10 kOhms impedance might be able handle it without issue, yes/no?

 

[agedhorse]

Just curious @agedhorse. Seems a DI like the countryman 85 which has a speaker input mode with 10 kOhms impedance might be able handle it without issue, yes/no?

Maybe, but the ground should be lifted. Note that I do not recommend this.