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Hi guys,
I have a Blues Junior amp that does not have a line out .
It only has speaker and ext speaker outputs.

Im wondering if I could plug from the main speaker output straight to the 002 rack
with a lead that has a 10 db attenuator ( A tech made the lead when I used to take
audio from the desk to a video camera ).
We recently moved to a townhouse type setup and there is no way I can
mic my amp to record. Ive looked on billm s site but he doesnt have instruction
on where to take a line out from.

Has anyone had this problem and how to get around it without spending money ...lol
Also will I do damage to the amp by doing this?.

Comments

dvdhawk Sun, 03/27/2011 - 15:16

I agree with Jack, 10dB isn't going to be enough. Plus the smallish transformer you'll likely find inside a 10dB pad may not be rugged enough to put up with that much wattage without distorting, warming up, or burning out. The windings are probably a pretty fine gauge of wire on a 10dB attenuator.

There are DI boxes made just for your job, such as the Whirlwind Director which isn't too horribly expensive. Rapco / Horizon makes a Speaker Level Direct Box ( SPL-1 ) which is probably slightly less expensive. (I'd add links, but I wouldn't know where to start shopping for musical gear in Aus. )

Anything of that nature will do, but regardless of how you bypass the speaker you'll lose some of the Blues Junior's cool signature sound.

SunDaze Sun, 03/27/2011 - 16:23

mmmm , cant find it , damn it.
I know its like maybe 5 resistors and should be easy to do if I had the right value resistors and the drawing.
If you have been down this road , can someone point me in the right direction , because Im so over sifting through all the shit on the net to get
to the right place.
spending more than 10 bucks is not fair cause I just spent money on some kinman pick ups and we are doin busking in a new town at the moment
cause we lost our work due to a cyclone ( get the violins out hahaha ) .

TheJackAttack Sun, 03/27/2011 - 17:45

You can purchase those pads from Whirlwind (XLR) in 10dB, 20dB, 30dB and 40dB. I think you should check out that [="http://www.rapcohorizon.com/p-16-spl-1.aspx"]Rapco SPL-1[/]="http://www.rapcohor…"]Rapco SPL-1[/] or just get a pair of the Whirlwind Imp 40dB pads. If you have to save up, that is probably still the best option. Now that I have said this however.......

Have you called up 7th Circle Audio? They're in your neck of the woods relatively speaking. [[url=http://="http://www.seventhc…"]7th Circle Audio[/]="http://www.seventhc…"]7th Circle Audio[/]. Even if they don't make what you want they might be convinced to build you a box or direct you to another DIY local that could help you out. It really isn't hard to do if you have the math correct for your particular application.

Boswell Mon, 03/28/2011 - 02:57

You have to regard the speaker terminals of the guitar amplifier as a differential voltage source, and should not connect them to the 002 interface via a conventional unbalanced attenuator. If you use an unbalanced connection, the ground will give you all sorts of trouble, as there could well be amps of current trying to find its way to mains earth down that lead. Additionally, several makes of guitar amplifier use H-bridge drives, where both speaker terminals are driven (antiphase) to get 4 times the output power from the same supply voltages.

You can avoid this particular problem by using a balanced attenuator and going into a balanced input on the 002 using a 2-wire plus screen cable. Wire the attenuator output to an 002 line input using standard TRS leads. For the attenuator input cable, take the ground (cable screen) to the guitar jack sleeve, not to the speaker. Connect the two inner wires to the speaker terminals.

As the others have said, a standard DI box is no use for this job, as the active ones are the wrong way round and the passive (transformer) ones will saturate magnetically and could burn out when fed the guitar amp's speaker voltage. What you really need is a re-amp box, for which the cable and balanced attenuator described above is a poor substitute.

dvdhawk Fri, 04/01/2011 - 10:07

jkchuma, post: 367762 wrote: Here is a DI box made specifically to do what your asking.

I recommended a couple less expensive versions in my first reply. Unfortunately, he has a $10 budget - as he's been displaced by the hurricanes and subsequent flooding that have hit Australia so hard.

Given your situation SunDaze, I've got an old Rapco here I'd give you, if we can find a way to ship it around the world for a reasonable price.

Kapt.Krunch Mon, 04/04/2011 - 03:19

SunDaze, post: 367299 wrote: Hi guys ,
I have a Blues Junior amp that does not have a line out .
It only has speaker and ext speaker outputs.

Blues Jr.s have Ext Speaker out? Mine doesn't. It has one speaker out. Is your's a new Hot Rod one, or an older one? I think the new ones do have an "Ext Spk" out, but the older ones have only one speaker out, and a jack for the "Fat Switch".

Just making sure you realize that.

Kapt.Krunch

BobRogers Mon, 04/04/2011 - 05:16

Since you can use the line/instrument inputs on channels 1-4 of the 002R, there's no real need to use a cheap DI box. Just plug into channel 1 in the back of the 002R and use Amplitude or whatever amp sim came with you PT package. If you can get a really good DI or splice in to the Blues Jr. before the power amp (which I don't recommend for a first project) that will improve the sound. But if money is tight do the best with what you have.

BobRogers Mon, 04/04/2011 - 05:24

TheJackAttack, post: 367607 wrote: Well, there is no benefit to going through the amp at all if silence is your goal since he speaker itself is what gives it it's sound. Send it direct to your interface and monitor from the interface headphone amp.

I don't think that's true. There may be a lot of tone in the power amp/ speaker, but the preamp circuit is responsible for a lot.

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