Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: J Rindt on July 02, 2012, 05:05:16 pm
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My friend has a Dr Z Route 66. He wants me to add a "line out" for the FOH guy at his church. I am not sure the best way to go with this.
What do you guys suggest for:
Guitar player on stage.
Has his own monitor, and a speaker cab.
Needs to get his guitar signal to the FOH board, and to the speaker cab.
What is the "best" solution for this amp/situation.?
Thank You
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I've built this several times and include it in nearly every amp I build.
The trans if from Webers and only costs a few dollars (<$3).
I've also built this in a project box with a 1/4" jack on a pig tail and plug it inline with the speaker.
Instead of R1, I use a 100K LIN pot. the input is just tapped off the speaker
The trans is small! it is easily fried with a full power from the amp, so when you are dialing it in, be sure to set the R1 pot at full 100k and the R2 pot to 0 ohms. play a bit hooked up to the board and slowly dial down R1 till it is loud on the board. R2 can now be used to cut the level.
The sound quality is quite good, however in some amps it can sound a bit flat, Weber suggests adding a bright cap, but I've found it is easily fixed on the mix board with a bit of treble added.
Ray
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I am not sure I know what you are describing.
Is there a Schem/Pictorial, or something that I am not seeing.?
Thanks
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[sidebar] :icon_biggrin:
One of my job responsibilities is overseeing FOH for a church, and I am a big believer in mic'ing actual cabs, even if there is a cab simulator built into their FOH mixer. Line outs generally sound pretty sterile, IMO. Our solutiion is to mic an extension cab in the green room so the guitarist can turn it up as loud as he wants. Many churches use isolation boxes like http://www.chrisfromcanada.com/guitar-amp-isolation-boxes/ (http://www.chrisfromcanada.com/guitar-amp-isolation-boxes/) in order to achieve the tone they want while controlling volume.
[/sidebar]
...but back to your actual question.
With an amp like the Route 66 that gets most of its mojo from PI and power tube distortion, you'll lose all the "good stuff" if you take the line out from the preamp. Seems to me that stingray_65 had the right idea in tapping off the speaker (or output transformer).
If I were you, I might suggest that your friend buy a Mini MASS or a MASS Lite and be done with it, but if he wants something built-in, check out this thread as a start for schematic ideas: http://www.el34world.com/Forum/index.php?topic=13376.0 (http://www.el34world.com/Forum/index.php?topic=13376.0)
If he's always going to have the speaker cab connected when he uses the line out, you could omit the 8R/20W resistor and SPDT from Sluckey's schematic in that thread, which would save a lot of space, but otherwise you need some kind of dummy load to load the output transformer. I've read that purely resistive loads can be hard on the amp and will yield less-than-stellar results, although I don't know much of the theory behind that assertion - maybe one of the more experienced guys around here can chime in about that (or disagree). Instead, you could make something using a reactive load like a speaker coil/magnet, or use a hybrid approach like Aiken does at http://www.aikenamps.com/spkrload.html (http://www.aikenamps.com/spkrload.html).
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I am not sure I know what you are describing.
Is there a Schem/Pictorial, or something that I am not seeing.?
Thanks
OOPS! the missing link
https://taweber.powweb.com/store/balun.jpg
https://taweber.powweb.com/store/magnetic.htm
last transformer, all the way down at the bottom.
I see they raised their price on this, I used to order a few at a time when I would order from them because they are so inexpensive.
I'm not all into bashing some one's products, but I highly recommend to NOT buy the XLR panel jack from there, a nice metal switchcraft can be had else where. Even radio shack has a nicer XLR panel jack.