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tot_Ou_tard
April 7th, 2009, 07:33 AM
An amp DI box like the Red Box DI still needs the amp to see a speaker load. These are designed for stage use so that one can run the amp & use the DI to send signal to the PA rather than miking the cab.

For home use with headphones would using a speaker nailed to a board with the cone removed work? Would it sound good? Are there well designed dummy speaker loads?

tunghaichuan
April 7th, 2009, 09:03 AM
An amp DI box like the Red Box DI still needs the amp to see a speaker load. These are designed for stage use so that one can run the amp & use the DI to send signal to the PA rather than miking the cab.

For home use with headphones would using a speaker nailed to a board with the cone removed work? Would it sound good? Are there well designed dummy speaker loads?

What are you trying to achieve here, tot?

Some of Weber's attenuator products (http://www.tedweber.com/atten.htm) have a speaker motor, which is just a speaker minus the cone. I have an older Mini Mass which has a speaker motor. It does not have a headphone out, though. In fact the only product on that page (https://taweber.powweb.com/weber/hpa50.htm) for headphone use has resistors only, not a reactive load like the speaker motor.

The Palmer attenuators (http://www.palmergear.com/pga04.shtml) seem to be well regarded, but are expensive. EDIT: It looks like you can plug headphones into the back of the unit. I have not tried one of these, so I can't comment on the sound quality.

HTH,

tung

tot_Ou_tard
April 7th, 2009, 03:56 PM
What are you trying to achieve here, tot?

I love the tone through my Gries 5 & was just fantasizing about getting that approximating the tone and feel through headphones.

The Red Box DI has cab simulations & a line out, but the amp still needs to see a speaker load. It just seemed to me that if I plugged in a speaker without a cone, then he amp would be happy with the load & the speaker would make no sound.

tunghaichuan
April 7th, 2009, 04:06 PM
I love the tone through my Gries 5 & was just fantasizing about getting that approximating the tone and feel through headphones.

The Red Box DI has cab simulations & a line out, but the amp still needs to see a speaker load. It just seemed to me that if I plugged in a speaker without a cone, then he amp would be happy with the load & the speaker would make no sound.

You can substitute a resistor or several resistors for a speaker load to use with a Red Box like product and an amp. I do it with my VJ all the time. I have one that I made of four 32 ohm, 5W resistors in parallel for an 8 ohm load. You could also buy one of Ted Weber speaker motors and use it with the Red Box.

You'd probably obtain the best results by running the line out into a small mixer and then using the headphone jack to monitor the sound. Your amp is not going to sound like it does with a speaker attached, though. But it might be good enough for headphone practice.

tung

tot_Ou_tard
April 7th, 2009, 04:14 PM
You can substitute a resistor or several resistors for a speaker load to use with a Red Box like product and an amp. I do it with my VJ all the time. I have one that I made of four 32 ohm, 5W resistors in parallel for an 8 ohm load. You could also buy one of Ted Weber speaker motors and use it with the Red Box.

You'd probably obtain the best results by running the line out into a small mixer and then using the headphone jack to monitor the sound. Your amp is not going to sound like it does with a speaker attached, though. But it might be good enough for headphone practice.

tung
Is a speaker motor just a speaker without the cone? Cause I've got the stock speaker from my AD30VT that I could remove the cone from.

I would have it go to my mixer & then to my cans as you say.

I'll bet that it won't sound as good as my Tonelab, but maybe it would be worth the experiment if I found a used Red Box at a good price.

tunghaichuan
April 7th, 2009, 05:53 PM
Is a speaker motor just a speaker without the cone? Cause I've got the stock speaker from my AD30VT that I could remove the cone from.
[QUOTE]

That's basically all it is. You could try it, it might be a good experiment.

[QUOTE=tot_Ou_tard]

I would have it go to my mixer & then to my cans as you say.

I'll bet that it won't sound as good as my Tonelab, but maybe it would be worth the experiment if I found a used Red Box at a good price.

Even less expensive is the Behringer GI100. It sounds about the same as the Red Box, although it only has the 4x12" sim and not the additional combo sim setting like the Red Box.

tung

tot_Ou_tard
April 8th, 2009, 05:37 AM
That's basically all it is. You could try it, it might be a good experiment.



Even less expensive is the Behringer GI100. It sounds about the same as the Red Box, although it only has the 4x12" sim and not the additional combo sim setting like the Red Box.

tung Thanks tung. I'll look into that. Do these types of gizmos work with a tube preamp or pedal into them & then direct to the mixer?

The more I think about this idea the complicated it seems. I am sure that if you just removed the cone & screwed the speaker cage to a board that it would make a buzzing & rattling noise as the speaker motor passed vibrations to the board.

One could try incorporating some acoustic foam somewhere. If it was easy to do someone would have already made a good sounding all in one unit. You are getting close to iso cabs in any case & should probably just go that route anyway.

This brings up a question that I hadn't thought about. How much sound is generated in a cab by vibrations directly transfered to the baffle & then to the cab? I'm not gonna rip the cone out of my scumnico to find out. ;)

tunghaichuan
April 8th, 2009, 09:17 AM
Thanks tung. I'll look into that. Do these types of gizmos work with a tube preamp or pedal into them & then direct to the mixer?


According to the Red Box manual (http://87.106.71.220/files/huke/proclass/redboxclassic/manual/RedBox_BDA_1_0.pdf) the Red Box will accept speaker level and line level signals. You may have to boost the signal to get it up to line level when using a tube preamp or pedal when using them with the Red Box. The Behringer GI100 manual (http://www.behringerdownload.de/GI100/GI100_ENG_Rev_A.pdf) shows you can plug either a guitar into the input or a speaker out. The GI100 is a direct box and can be used as such without the 4x12" cab simulation.



The more I think about this idea the complicated it seems. I am sure that if you just removed the cone & screwed the speaker cage to a board that it would make a buzzing & rattling noise as the speaker motor passed vibrations to the board.

One could try incorporating some acoustic foam somewhere. If it was easy to do someone would have already made a good sounding all in one unit. You are getting close to iso cabs in any case & should probably just go that route anyway.


Weber has done this with their Mass series, but not for headphone use. Another thing to consider is that if you try to make your own speaker motor, the wires to the voice coil on the speaker are very thin, very fragile and easy to damage. It may be hard to make such a device by removing the cone. That's why I suggested you get one from Weber.



This brings up a question that I hadn't thought about. How much sound is generated in a cab by vibrations directly transfered to the baffle & then to the cab? I'm not gonna rip the cone out of my scumnico to find out. ;)

OD generated by the amp is a complex equation of the output transformer, the speaker, the cabinet, the guitar and the guitar player. This is why the speaker sim boxes such as the Red Box and GI100 don't really sound like a cranked amp. Such devices leave out the speaker and cabinet from the equation so you don't get their interaction.

If you need to practice quietly, sometimes the simplest way to accomplish this is to use a modeling device.

tung

Rx Tone
April 8th, 2009, 02:31 PM
You can use a Power Brake or a Power Soak as a dummy load, right?
I forget who makes those, though.
google 'em.

goonrick
April 8th, 2009, 03:16 PM
A speaker with the cone removed is a speaker motor. It's bulky and must be rated appropriately for power, but should supply an appropriate reactive load to the amp that would be better suited than a purely resistive load.

If you're feeling adventurous, you could remove the steel basket from the speaker assembly and attempt to mount it in a box or something.

tot_Ou_tard
April 8th, 2009, 05:58 PM
Hey the Weber speaker motor below

http://www.tedweber.com/motor.jpg

is a lot like I was imagining with the acoustic foam & a deconed speaker.

tung, yes my Tonelab works great, but you know about curiousity & the cat.

I am not really going after cranked screaming tone. I'm more trying to get the full, dynamic, touch-sensitive clean to just breaking up tone & feel of my Gries 5. I'm sure a lot of it has to do the the speaker pushing air, but it can't hurt to try.


A speaker with the cone removed is a speaker motor. It's bulky and must be rated appropriately for power, but should supply an appropriate reactive load to the amp that would be better suited than a purely resistive load.

If you're feeling adventurous, you could remove the steel basket from the speaker assembly and attempt to mount it in a box or something.

Yeah I just might do that.

The speaker I'm thinking of using is an 8Ohm 30 watt speaker. My Gries 5 is a 5 watt amp with an 8 Ohm out. It should woork fine.

tunghaichuan
April 13th, 2009, 07:45 AM
tot,

I tried an experiment last night.

I took one of my Champ clones hooked it up to a Behringer GI100 cabinet simulator and plugged in a dummy load made of 5W cement resistors. Then I ran the line out of the Behringer into a mixer and monitored the sound with headphones.

The results were marginal. When I set the amp up to be clean, it was too clean. Very hifi sounding and not in a good way. Even though the Behringer has a 4x12" cabinet emulation, it didn't seem to help much.

Next I tried cranking the amp up, but the distortion was gritty, and sounded very solid state. I got better results using a distortion pedal, but with the pedal there were no dynamics.

I think the problem is lack of speaker/OT interaction. Also, the headphones do not color the sound like a guitar speaker would.

I think my next experiment will be to hook up my Weber MiniMass, which does have a speaker motor in it to see if this makes a difference.

tung

goonrick
April 13th, 2009, 07:51 AM
I think the problem is lack of speaker/OT interaction. Also, the headphones do not color the sound like a guitar speaker would.

I think my next experiment will be to hook up my Weber MiniMass, which does have a speaker motor in it to see if this makes a difference.

tung

Please report back on this. I've never tried it before and am interested in how big a difference it makes over a resistive load. Everything I've read indicates that a tube amp needs a reactive load, which is what a speaker is (combination of resistance, inductance and capacitance). I'm willing to bet it makes a big difference.

tot_Ou_tard
April 13th, 2009, 10:04 AM
Cool beans tung!

Thanks for the experimental data. I'm looking forward to the MiniMass test!