Reverb and C+ strange thing happens.

[tony777]

Hey!

I just discovered this strange thing to my DRGX c+

When I engage the reverb, the amp also changes the sound from harsh to scooped sound, kind of raising the prescence from 5-10.
IMO very nice and to me it seems like it always have lacked this, since my 60watt always had this extra scoop.

I tried to connect the reverb tank of my MKIV, and the same thing happened.
I tried to patch the FX loop, switch from simul to class a, 8 ohms output vs 4 ohm, still the same.
I also tried to change tubes.
Any ideas?

Kind regards
Tony

 

[Boogiebabies]

The reverb ground is going bad at the washer under the preamp board. The result is that the reverb circuit is being held just above ground and turning your reverb into a mini 1 Watt amp. The fuzzy and scooped tone is a certain sign. Spitting and strange tones can also happen. Other than ripping the preamp board out to clean the ground, use the 1 wire mod and solder it to the sleeves of the two reverb cables that plug into the chassis and your problem will be solved.

 

[tony777]

Do you mean to shorten the sleeves of input and output the reverb cable?
I did that, and there was no change.

Btw, do you have a picture of what you did?
I searched for your .mac C+ website, but i can't find it.

regards
Tony

 

[Boogiebabies]

PM me your e-mail address and i'll send you a copy.

 

[tony777]

Still no luck though.
I am curious if it's only my amp, so I will ask if anyone with a simul/reverb C+ or any reverb C+ will try out their amp?

The difference is between no reverb and full reverb, the difference slightly increases along with the amount of reverb that's added.

I have recorded a sample with my amp, whre the first part is no reverb and then I engage the reverb at 10 with a footswitch.
You WILL hear the difference.

http://idisk.mac.com/tonykareid-Public/C+reverb_sample.mp3

thanks
Tony

 

[tony777]

The Reverb is set at 10 (maximum)

So your amp sounds the same?

That's the thing I want to know, if it's just the nature of the beast;-)

regards
Tony

 

[tony777]

It doesn't really matter what settings I use, I can hear the difference at all settings, and both clean and distorted sound.
but anyway.

vol 1: 6
Treble 10 pulled
Bass: 2 Pulled
Mid: 8
Master 1: whatever suites you, don't get deaf but Pull.
Lead Drive 10 Pull (obviously in metal)
Lead master: 2 Pull
Typical V-shape at EQ
Prescence: 6
Reverb: 10

I can hear the difference in tone slightly increase with the amount of reverb I add.

Cab Mesa standard recto 4x12 (oversized)

Guitar Ibanez Jem with bridge pickup, tuned to drop C.

Thank you for trying
Tony

 

[Stonge]

when i get to the my rehersal space in a few, I will see if I can tell about what you are taliking about. but just from the clip, it sounds like your tank is ****. mine for sure sounds like there is more life to it(tank).

 

[merendina]

The Reverb is set at 10 (maximum)

So your amp sounds the same?

That's the thing I want to know, if it's just the nature of the beast;-)

regards
Tony

It's not the right way of the reverb sound Tony..

a friend of mine have the same problem, the sound with the reverb set to 10 is distorted and less volume.
the reberb affect little bit the sound..

Mine sounds good, clean sound, with balanced mix between dry signal and wet and the reverb don't affect the sound, just add reverb

 

[tony777]

I connected the reverb tank from my MarkIV and it sounded the same, so I am not quite sure that it's the reverb tank then.
And yes it is the model 9AB2A1B.

 

[GIG4FUN]

I suggest you replace V4 preamp tube. It's your effects/reverb driver IIRC.

you said in your first post that "I tried to change tubes" well I don't know if you actually did and which ones LOL

I wish you well.

 

[tony777]

you said in your first post that "I tried to change tubes" well I don't know if you actually did and which ones LOL

Hahaha, great!
btw, I did change the tubes, but my expression wasn't the best.
You should hear me in norwegian, I am very good at that language :lol:

Anyway, I have played all my 12ax7's this morning, about twenty or so spare tubes, and the effect is still the same, no matter which tube.
But not to worry too much I ended up with another sets of preamp tubes that made the amp sound much better, and I almost never play guitar with reverb, so WTF!
What I came up with was the mesa 12ax7 at V1 and V2
electro harmonix at V3 and V4, and a fender (made in china) at V5
The tube in V5 didn't make any noticable difference as I could hear though.

These tubes are unused, so it might be the reason for the result.

I had some TAD's in the amp previously, and they were the ones coded RT003, which I don't think is the best ones for high gain.
http://www.tubeampdoctor.com/index.php?cPath=21_60_63
I have a pair of TAD RT001, in my other C+, and they have more gain to them.

And one thing leads to another.
Again I had to compare both my C+'s and this time I actually liked my simul better, with a thicker tone, and bit less bass rumble, but the 60W still have more rawness to it, and will be better for scooped extreme metal, but gets a bit too fizzy for soloing.

Bottom line:
I am not sure about the reverb thing yet, and
Do never get two or more C+'s
It will drive you mad!

Tony

 

[tony777]

Tony,
Try the presence set at 0 and see what the effect is like while turning up the reverb slowly from 0-10. I find the presence in a simul too high at 6 in fact I dont use it much if at all at higher volumes. I wonder if a "high" presence setting of 6 combined with the reverb is causing this effect.

Nope, the effect is still there

 

[Boogiebabies]

Just out of curiosity, with the tank unplugged from the chassis, does turning up the reverb knob add loud crackles and hissing ?

 

[tony777]

Just out of curiosity, with the tank unplugged from the chassis, does turning up the reverb knob add loud crackles and hissing ?

No, it's dead quiet, and sounds just like when the reverb is off or at zero

 

[Boogiebabies]

Scheiße !!!!

Let me go see how my four react. I post back later.

 

[Restless Rocks]

Likely the C+ would benefit from the 3K3 ohm resistor in series with the FX loop. (standard MkIII rev mod.) This might keep the reverb pot from loading the PI input.

 

[tony777]

Likely the C+ would benefit from the 3K3 ohm resistor in series with the FX loop. (standard MkIII rev mod.) This might keep the reverb pot from loading the PI input.

Any thoughts on that, since it's a bit over my head :?

 

[tony777]

I got myself two brand new mesa 12AX7's and put them in V3 and V4, so my simul has brand new mesa tubes in V1, V2, V3, and V4, and the weird effect disappeared.

I doesn't make sense to me, since I have switched between more or less twenty different tubes in the slots, but yes, it did disappear. Gone!
I haven't swithced back to the previous tubes, since the amp sounds as it should.
Maybe I will later.

8)

 

[GIG4FUN]

haha Told you V4 needed it. I win... :wink: