Tube amp for acoustic electrics

[M Fowler]

I built Tony King from Brooks & Dunn band a 50w 6L6GC Rocket preamp tube amp for acoustics

.

Just curious, does this mean you built just the preamp section of a 50w Rocket (prior to the LTPI and power amp) ?

And if so, then did you run it straight into the PA system?

With respect, 10thtx

Complete amp head. TW Rocket pre into LTPI and 6L6's. Schematic was basic design but changed to fixed bias.

[tictac]

FYI, if your acoustic guitar has piezo pickups the input Z should be higher than the typical 1M grid resistor. 3M3 to 10M is a good range. Otherwise you loose a bit of high end...

TT

[martin manning]

Most acoustics with factory pickups have on-board preamps, and some systems have multiple pickups of different types. Taylor's system can go direct to a mixer XLR input using a TRS to XLR cable. To your point, best to find out what this guy is using.

[10thTx]

Complete amp head. TW Rocket pre into LTPI and 6L6's. Schematic was basic design but changed to fixed bias.

Mark, THANKS for sharing your work! I appreciate the response.

As an FYI, I did something kinda sorta similar at some level for building an amp head in a "zero noise" band setting where the amp head is put into a PA system. It's been working flawlessly that way for 3 years now with quite a few different players using it.

I used a 100w dummy load resistor and an H&K Red Box. It actually is using JJ 6V6's instead of 6K6's to have a little more headroom.

I should add that my Larrivee OM-03 acoustic sounds great thru this amp going into a slight delay and then plugged into the FX return. And you can still control the volume with FX level and the PPIMV.

With respect, 10thtx

[Ron Worley]

Most acoustics with factory pickups have on-board preamps, and some systems have multiple pickups of different types. Taylor's system can go direct to a mixer XLR input using a TRS to XLR cable. To your point, best to find out what this guy is using.

Very good idea, I will see what his custom made acoustics use. He is looking for something in a 30W combo amp, and will want a DI to go into a PA. He mentioned reverb and believe it or not Trem.

Keep the good ideas coming, please!

[martin manning]

I think it will take 2x 6L6 to get a really clean 30W out, so I'm liking the clean channel-only low-plate ODS 50W idea. My acoustic actually sounds pretty good through the clean channel on my 100W 124-ish amp. In your case you could use the OD tube for the reverb, and an isolated line out could be added using a 600-600 transformer such as Jensen JT-11-FLCF.

[JMFahey]

No tube amp will be "better than his Acoustasonic".

He will end up with an expensive, heavy (the artist is a solo acoustic act, so will have to carry everything by himself), underpowered, inflexible and funny sounding amplifier.

Fender amps are "crystal clear" to Rock guys only, but to no one else, specially Acoustic players.

All this is based only on the (often misapplied) blanket statement "tubes are better, period" which sometimes is true, sometimes is not; definitely not in Acoustig Guitar land, or there would be a significant percentage of Acoustic Tube amps out there .. there is not.

If anything, the OP could pull the amp section from the Acoustasonic and mount it in its own case, turning it into a head, and build a KILLER cabinet.

Of course I am wasting my time, I am preaching in the wrong Church

[tictac]

The Crate Acoustic amps are really nice too.... The biggest one they make has a ported cab and you get some good bass response, plus built-in digital effects.....

I've got a Fishman SA-220 which not only amplifies acoustic guitar well but doubles as a portable PA system that is easy to carry and really projects....

my .02

TT

[RJ Guitars]

I built my own version of a TW Songwriter 30 last year (http://ampgarage.com/forum/viewtopic.ph ... pedal+mule) and I've used it many times with an acoustic guitar. Each time I have been pleasantly surprised in how well it works. There are probably good tweaks that could be done to dial it in for a specific guitar or specific sound but it's pretty stinkin' good just the way it is... plus it is also the best pedal friendly amp I have in the herd. This makes it real easy to use an AB switch and have both guitars, reverb, tuner, etc., all in a fairly simple package.

[Leo_Gnardo]

I built my own version of a TW Songwriter 30 last year and I've used it many times with an acoustic guitar. Each time I have been pleasantly surprised in how well it works. There are probably good tweaks that could be done to dial it in for a specific guitar or specific sound but it's pretty stinkin' good just the way it is.

What pickup on your acoustics, or does your amp work well with anything & everything? Which speaker did you install?

[RJ Guitars]

I built my own version of a TW Songwriter 30 last year and I've used it many times with an acoustic guitar. Each time I have been pleasantly surprised in how well it works. There are probably good tweaks that could be done to dial it in for a specific guitar or specific sound but it's pretty stinkin' good just the way it is.

What pickup on your acoustics, or does your amp work well with anything & everything? Which speaker did you install?

All my acoustic electrics have piezos so they can be a little "Quacky" thru whatever you play thru... especially the one with no preamp. When I played through the house sound system at my church I found that if I use a Barcus Berry Piezo Buffer it not only takes out the Quack but also smooths and sweetens the tone. Using this same setup really preps the guitar for giving great sound when going direct into the amp.

For a while I was using a Fender ACOUSTASONIC amp for the acoustic guitar until I found I could go direct to the Pedal Mule and get good sound. One less amp on stage and an A/B switch made this a very useful discovery.

I used an "ECHO" alnico 40 watt 12" speaker. These are from a Chinese manufacturer that sent them to me as a demo (in hopes I would market them in large quantities). Decent sounding speaker although I would say it's not enough speaker if you push the amp really hard with the electric guitar. I think for this amp a speaker that is really transparent like a Neo Magnet 100 watt would be ideal but I didn't have one available when I built this amp. The amp is already heavy so I'm not inspired to suggest anything with a ceramic magnet.

rj