Fender Concert Rivera

[dscottguitars]

Hello, I am re-capping my Fender Concert 112 Rivera Amp and while I am in there I am wondering about modifying the lead/distortion channel. I never liked the sound I would get from it, it was always rough-no smoothness for a 3-finger chord.

The coupling caps are small, .0047 and .01. The gain pot is 3 meg which seems quite high. The master pot is 250K, which seems low. The tube for the gain part only uses 1 of the triodes leaving the other one untouched. Smaller caps lets more highs through. Pots are opposite, the larger value more highs. So, the small caps & gain pot let mostly highs through,the master pot filters them out.

I want change the caps: .02 & .03. Change gain & master pots to 1 meg, like the volume pot. Then connect the plate, grid and cathode of the unused triode and change the resistor and capacitor on the cathode. I have different 12--7 tubes to experiment with- guess 12au7 the best. Any advice would be helpful.

Schematic: http://www.ampwares.com/schematics/concert_ii_83.pdf

Thanks

[vibratoking]

There are VERY long threads about mods to that amp on The Gear Page. I own that same amp and have found ways to make it more acceptable to me. The easiest is to use a patch cable in and out of the effects loop and use the extra stage for gain. This alone makes the amp much more acceptable to me. I also swapped out the orginal speaker which had extremely farty bass for an Eminence Tonker. I am pleased with that speaker.

I have not tried any of the mods on The Gear Page threads. Just never found the motivation or time for them.

[selloutrr]

listen to the amp record the tone if you can before you start any modifications.

each time you do a mod record it and compare. Like an eye test ... better ... worse... move on to the next or restore to stock?

if you are getting overly dirty chords.. are you over driving the input to hard? pedals ... active electronics? humbucker pickups? these amps were designed for fender amps - single coil.

try a pad between the guitar and the input jack. it should clean up the image and still give you the "rock"

Rivera also offers great customer support, if you shot them an email i'd be surprised if they didn't assist with suggestions.

[dscottguitars]

Thanks for the quick reply. I like both suggestions, especially the effects patch. I used humbuckers w/split coils, no active electronics or pedals, just straight into the amp. I'm not an electric player, which could be why I'm not getting the tone I want. I play acoustic mostly, but wanted to play electric rhythm classic rock, so I'm not sure how to use the three volume controls properly. I've only used every combo I can think of and get dirty overdriven overdrive or not enough. I'm looking for something like the tone in Sweet Emotion and Stranglehold.

I am still wondering about the choice of the values on the caps and pots. Is there a link to the support at Rivera?

Thanks again

Daniel

[selloutrr]

It's on rivera's home page. scroll to the bottom on the page.

http://www.rivera.com/


If you are playing an acoustic / electric guitar it opens up a whole new can of worms. the pickups in acoustic / electric guitars are harsh, muddy and difficult to flatten out / balance. try scooping the mids and slowly rolling up the treble with the bass at 12 o'clock once you find the point at which the treble is to almost to much but isn't. adjust the bass for the low end woof, dialing back just before the speaker woofs when you dig in. now bring the mids up until it fills out. I've found the batteries life also makes a huge difference in the tone.

The distortion / tone you hear on the aerosmith albums is the blending of the cranked marshall with a soundcity 120 the soundcity stays clean and gives great cut while the marshall breaks up and gives the saturation paired up and blended you get the sweet crunch with note definition.

[vibratoking]

I've only used every combo I can think of and get dirty overdriven overdrive or not enough. I'm looking for something like the tone in Sweet Emotion and Stranglehold.

I believe Strangelhold is a Gibson Byrdland through either a Dual Showman or Twin Reverb. Either way, the amp is full up. I saw him several times in the mid to late 70s and he always used the Dual Showmans.

BTW, the Concert has a very nice clean channel OD when cranked. It is the best feature of that amp, IMO. Although, it is probably more blues than rock.

[dscottguitars]

Hi, I play acoustic through a PA usually. I've tried on this, once, that was all it took. I have an electric guitar, I just play clean country. But would like to play around with some old favorite songs, I just can't get the tone I wanted. I'll check out the gear page suggested and get some ideas there too.

Maybe I need an attenuator to the speaker?

[selloutrr]

a reverb or chorus pedal and compressor pedal on acoustic guitars goes a long way to making them more real when used with an amp or steril PA system.

The one exception to this is the Gibson Chet Atkins SST it was built to be an electric guitar with an Acoustic timbre. They sound fantastic. I was amazed how much gain mine has, I over load most input inputs so I run it pretty choked back which adds to the acoustic tone and stunts some of the treble. The other benefit - ZERO feedback! and it handles distortion / fuzz pedals great. Plays like a les paul custom sounds better then a D.I.'d martin or taylor. It's worth checking out if you gig.

An attenuator to the speaker will allow you drive the amp harder but the amp wasn't designed to be a rock monster, I'm not sure how much you would gain. If you have a friend who has an attenuator I'd try it before I buy it.