Blues Jr. >>>>>> Jettenuator:

[Eleanor Fudd]

I just received a Jet City Jettenuator which I bought myself for Christmas in order to do low-volume recording. I see that it is also a load box, which means that I should be able to send my Blues Jr.'s signal to my Babyface for silent recording. The Blues Jr. has a line out for external speaker and the internal speaker can be unplugged. The attenuator has 4, 6, and 8 ohm inputs (the amp is 8 ohms) and also has a speaker out, a line out, and a MicSim out (XLR) as well as line level and attenuator dials.

The question is: what do I have to plug or unplug into what, in order to get the silent amp signal into the interface without exploding anything? Also: is it possible to put other devices or boxes before or after the attenuator?

There are instructions, but that's a far cry from good advice.
Thank you.

 

[snow lizard]

As far as I know, Blues Jr.'s have a 1/4 inch jack for the speaker and another for connecting a "Fat" footswitch. For convenience, they are beside each other on the back underside of the chassis. "Line Out" and "External Speaker" are 2 different things. Unless Fender changed this on newer models there should only be one speaker output.

 

[Eleanor Fudd]

Thank you, you're right. The speaker plug is for the internal speaker, and it is pulled and used to feed the external speaker, although in the case of the attenuator being the target, I expect that a patch cable is used and not a speaker cable.

 

[ecc83]

Thank you, you're right. The speaker plug is for the internal speaker, and it is pulled and used to feed the external speaker, although in the case of the attenuator being the target, I expect that a patch cable is used and not a speaker cable.

No, you should use a SPEAKER cable from the amp's speaker jack to the attenuator although at this power level it really wouldn't matter.

There is often a stern warning in amp manuals NOT to use a shielded guitar cable twixt amp and speaker. Sound advice though generally a 'guitar' cable could easily carry the 2 or 3 amps involved. Maybe don't try this with a very long 'curly' lead! Bottom line: a guitar cable should get you through the night but don't push your luck with a 100W head and a 4 Ohm cab. 30W and 8 Ohms? No sweat.

No, you should put nothing between the amp and the attenuator but you can put what you like in the feed to the Babyface. Pedals of any type and description but bear in mind, once 'in the can' the effects cannot be undone. You COULD use 'Y' cable and split the signal? One path is dry to left input. T'tother is buggered about to taste and goes to right input. Best of both, tune for maximum smoke!

Dave.

 

[Eleanor Fudd]

Thanks very much for the reply.

"" T'tother is buggered about......"" English, eh?

So speaker cable to the attenuator and patch cable from there to Babyface?

(Supplementary question, Mr. Speaker: ) Do I need an IR?

 

[arcaxis]

Would highly recommend having the BJ amp turned off when connecting or disconnecting the cables. Be sure all is plugged in before powering the amp up. Tube amps don't like having no load on the output transformer and could be damaged if powered and you happen to wail a chord through the amp with no load. The amp does have 'protection' in the speaker jack if just the speaker is unplugged, but not for an open ended cable plugged into it.

 

[ecc83]

Thanks very much for the reply.

"" T'tother is buggered about......"" English, eh?

So speaker cable to the attenuator and patch cable from there to Babyface?

(Supplementary question, Mr. Speaker: ) Do I need an IR?

Sorry! Translation into RP.."The other side of the split goes through whatever sound modifying devices you may choose and thence to the right hand channel of the Baybyface"

Otherwise, as you were..

Yes, we should ALWAYS connect up cold and the advance faders slowly, but sometimes we is impatient! I am I confess a bit cavalier with guitar amps but have never had a bother and can fix them if I did.

Dave.

 

[Eleanor Fudd]

Sorry! Translation into RP..

No, I meant that your vocabulary identified you as speaking English and not American.

 

[ecc83]

No, I meant that your vocabulary identified you as speaking English and not American.

Oh I see! Yes indeed, limey born and bred.
Rock on,
Dave.

 

[Nola]

Would highly recommend having the BJ amp turned off when connecting or disconnecting the cables. Be sure all is plugged in before powering the amp up. Tube amps don't like having no load on the output transformer and could be damaged if powered.

Is this true of a standard tube amp with the 1/4" jack unplugged? Like if I turn it on and the cable is on the floor before I plug in to the guitar.

 

[ecc83]

Is this true of a standard tube amp with the 1/4" jack unplugged? Like if I turn it on and the cable is on the floor before I plug in to the guitar.

No quite sure what you mean N? The fall-back, super safe advice with ANYTHING, PC, AI, amps and ESPECIALLY Fussy Wire! Is to have everything cold and off and connect all necessary cables THEN power up.

But! I am of the opinion that decent gear and especially guitar amps should be pretty bomb proof these days. Yes, be careful on a gig that you don't make embarrassing, loud buzzes and farty noises but a well designed* guitar amp, valve or solid state should cope with 'hot plugging' IMO.

The really only danger to valve amps is if you don't load it (to within 50% of indicated tapping) then drive the nuts off it. Solid sate amps SHOULD cope with no load but don't bet on it and a shorted speaker jack might destroy it but really should just pop a fuse or the amp go into a controlled shut down.

*Another BUT! There is a lot of cheap ***t about now (but even some 'famous' old designs were rather delicate) and valves are not as strong as they once were. Still, a 'flashed' valve should still just pop an HT fuse (but not all amps have them!) and NOT cause 'collateral damage' but cheaping out on components that are only jeeeeust up to rating means this often happens.

Dave.

 

[Eleanor Fudd]

Is this true of a standard tube amp with the 1/4" jack unplugged? Like if I turn it on and the cable is on the floor before I plug in to the guitar.

Good question !!! I'd bet the answer is 'yes.'

 

[arcaxis]

Originally Posted by arcaxis View Post
Would highly recommend having the BJ amp turned off when connecting or disconnecting the cables. Be sure all is plugged in before powering the amp up. Tube amps don't like having no load on the output transformer and could be damaged if powered.

Is this true of a standard tube amp with the 1/4" jack unplugged? Like if I turn it on and the cable is on the floor before I plug in to the guitar.

Not on the input jack where you plug the guitar into, only on the output side where a speaker would be plugged in.

 

[Eleanor Fudd]

Not on the input jack where you plug the guitar into, only on the output side where a speaker would be plugged in.

Right...... so if you turn on the head without it connected to a speaker or other load, you're in trouble.

 

[Eleanor Fudd]

It works! What lovely sound, direct and silent (to the outer world.) I'm very impressed. For me, this is the way to record electric guitar.
Thanks to all.

 

[ecc83]

Right...... so if you turn on the head without it connected to a speaker or other load, you're in trouble.

You could be but the very fact that the amplifier has no load will not, if it is of decent design, cause instant destruction, you would have to drive and quite hard.

The question is often asked "can I use a 16 Ohm speaker on my valve amp? It only has 4 and 8 Ohm tapps"

Yes, but, is the answer. If you had say a 50W amp and a put 16R speaker on the 8R tap at low (tuning up say) levels no problem. Even running that 1 to 2 "mismatch" * at modest 'pub' gig level would be fine but if you ran the beans off the amp with OP stage distortion, THEN spark could fly in the valves.

*We do not "match" any outputs to any inputs in audio. No, not even valve amps and speakers but that is a whole HEAP of other wriggly things that I am happy to go into if anyone really wants to know!

Just like to add: you like the sound? This is IMHO the best way to record bass guitar. Getting a good cab sound (need a good cab for one thing!) is tricky, bass is very penetrating and annoying and in any case every mortal thing in the room rattles!
Dave.

 

[Eleanor Fudd]

I think I'll need impulse responses to get this fine-tuned properly.