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    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Resistor as a load

ixe13

Member
2006-11-19 12:50 am
Hi,

I have this nice little Fender amp:

Fender Products: Vibro-Champ® XD


It has a line out and I can unplug the speaker so I can connect a different speaker cabinet to it.

Now this idea is, at night, i can use the line out to send the signal in my recording equipment and use headphones.

But, I dont want to use the speaker so i wont wake up the whole house.

Obviously i cant unplug the speaker and leave the amp without a load.

So I'm thinking of using a 10-15 watts 4 ohms resistor in place of the speaker.

Can I do that and use the amp for hours?

I understand that the resistor would get hot.

And what value of resistor would be safe?

Thank you in advance, guys

Yves
 

Brit01

Member
2008-07-04 10:35 am
I would assume the line out has a constant voltage/current output and is independent of the master volume. Just turn down the master volume to zero and use the line out to your recording equipment and use your heaphones from that.

I have this on my Marshall.
 

ixe13

Member
2006-11-19 12:50 am
I would assume the line out has a constant voltage/current output and is independent of the master volume. Just turn down the master volume to zero and use the line out to your recording equipment and use your heaphones from that.

I have this on my Marshall.

That's another option, will have to test this also.

I suppose the gain is the volume for the preamp, right?

I could use that to control the input to my recording equipment.

Will test it and report back for the curious ones...
 

ixe13

Member
2006-11-19 12:50 am
Hey guys,


The "line out" is for an external speaker. All of the gain and tone controls are in the circuit. Put a resistive load on the "line out" jack. You may need some amount of signal attenuation before you connect the amplifier to your recording equipment.

The line out of this amp is for a PA system or recording equipment.

Taken from the owner manual:

M. LINE OUT—Connect your recording or sound
reinforcement equipment here.
Use only a standard 1/4" mono plug.

Also this little Fender Amp is a class A circuit using a 6v6 tubes for power and a 12AX7 tube for the preamp.

Only the effects and modeling technology is solid state.

I must say, in this amplifier case, it's a well done mix of both technology.
The tube sound is there, and it still respect the tone I get out of the Stratocaster I'm using with it.

Through the years,I owned a Princetone Fender amp. a Bandmaster Fender amp and a Bassman Fender amp.

And this Vibro-amp has the Fender sound to it.

Very nice little amp.

And the price is ridiculous: 200$ :D
 
Thanks for the information
The link which you provided says nothing about a line out for recording. Only an external speaker output. "External Speaker Output Allows use with External Speaker Cabinet Line Output."
Nonetheless, this output should be fine as a line output. Just make sure that you terminate the output with a resistor so as not to damage the output transformer.
 

ixe13

Member
2006-11-19 12:50 am
Frank,

yeah! I see, it's totally confusing, They mean that the output jack that connect the speaker that come with the amp can be unplug to use a bigger or different cabinet.

All you have to do is unplug the actual 8 Inch speaker and plug in another cabinet.

On the Image/media tab on the link supplied, there is a photo of the back of the amp. Click on it and you can see the back of the amp.

But yeah, I re-read the spec with in mind the way you saw it and it does look like the way you discribed it.