6505+ bias mod??

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jessexxx

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i have a 6505+ that i am trying to love,...but it sounds flat,...one dimensional,...and believe it or not..lacking gain!!

i have only had it for a couple weeks and i have yet to do a tube change..(the dude who previously owned it put ruby's in it)...i am more of a jj kinda guy...so i am hoping the tube change will make it breathe and come to life....

i guess my question for ya'll is...does a bias mod make a significant difference??...more than just subtle?? for this amp??

every other 6505+ i ever tried seemed to be the beast of darkness i wanted...but i always played them with someone elses set up..(there guitar, cab etc.)...

my set up consists of a gibson sg with a dimarzio d-sonic in the bridge..and a mesa recto 4x12,..a guyatone fr3000v...

anyone that has some experience with this head and the bias mod i would appreciate your input..

thanx
 
6505 with not enough gain? you need to check yer tubes or something dude...take it to a tech. something is not right.

i do not have the bias mod, but i am pretty confident it's not going to help you with the gain issue....
 
A preamp tube change can drastically improve your amps tone.
6505's love JJ's too.

I also suggest maxing the accessible bias trim dial by turning it all the way down counter clockwise. This will give you a somewhat higher bias setting.
 
I just like amps that have overdrive that sound like the end of the world :D
 
jessexxx":35ecd6si said:
i have a 6505+ that i am trying to love,...but it sounds flat,...one dimensional,...and believe it or not..lacking gain!!

i have only had it for a couple weeks and i have yet to do a tube change..(the dude who previously owned it put ruby's in it)...i am more of a jj kinda guy...so i am hoping the tube change will make it breathe and come to life....

i guess my question for ya'll is...does a bias mod make a significant difference??...more than just subtle?? for this amp??

every other 6505+ i ever tried seemed to be the beast of darkness i wanted...but i always played them with someone elses set up..(there guitar, cab etc.)...

my set up consists of a gibson sg with a dimarzio d-sonic in the bridge..and a mesa recto 4x12,..a guyatone fr3000v...

anyone that has some experience with this head and the bias mod i would appreciate your input..

thanx

Flat and one dimensional are the typical traits of a 6505 love it or hate it. lacking gain is laughable, there is either something wrong with your amp, or the level of gain your looking to achieve is so far over the top it borders on unusable. (isnt the "+" model the one with an extra gain stage?)

try plugging directly into the head without any effects or gates to rule out those devices. then try swapping tubes maybe there is a tube fault somewhere.

As for the bias mod, i wouldn't play a 6505 without it, though warming up the tone and getting the bias out of crossover distortion might actually take away some of the qualities I think draw people to these amps. It will be less harsh distortion, a smoother more complex tone, a little less dry sounding.

In fact Id go so far as to say if that's not EXACTLY what you're looking to get out of a 5150 type amp, then there is no other point in playing one. IMO the harsh,brittle "crunch" those amps are known for is the only selling point.

I have a pic of the completed bias mod but cant find the instructions at this time... basically a resistor and a pot placed across and existing capacitor.
 
If I remember correctly, the "+" refers to the amp having two channels.
 
Core9":1pqwl3yn said:
If I remember correctly, the "+" refers to the amp having two channels.

It turns out the extra gain stage is in the clean channel. The other differences are separate eq for each channel and some type of crunch boost mode.
 
Frolid":2089ug5p said:
a 6505+ with almost no gain??? I've never heard of this :confused:

lacking gain actually,..compared to the other's i have tried..then again maybe my memory isnt serving me as it should!
 
D-Rock":23bcu0rc said:
A preamp tube change can drastically improve your amps tone.
6505's love JJ's too.

I also suggest maxing the accessible bias trim dial by turning it all the way down counter clockwise. This will give you a somewhat higher bias setting.

thanx man,...i already adjusted the bias as much as i can...it did make a difference ,...i was hoping with more adjustment it would have more dynamics,.
 
moltenmetalburn":287crbqp said:
jessexxx":287crbqp said:
i have a 6505+ that i am trying to love,...but it sounds flat,...one dimensional,...and believe it or not..lacking gain!!

i have only had it for a couple weeks and i have yet to do a tube change..(the dude who previously owned it put ruby's in it)...i am more of a jj kinda guy...so i am hoping the tube change will make it breathe and come to life....

i guess my question for ya'll is...does a bias mod make a significant difference??...more than just subtle?? for this amp??

every other 6505+ i ever tried seemed to be the beast of darkness i wanted...but i always played them with someone elses set up..(there guitar, cab etc.)...

my set up consists of a gibson sg with a dimarzio d-sonic in the bridge..and a mesa recto 4x12,..a guyatone fr3000v...

anyone that has some experience with this head and the bias mod i would appreciate your input..

thanx

Flat and one dimensional are the typical traits of a 6505 love it or hate it. lacking gain is laughable, there is either something wrong with your amp, or the level of gain your looking to achieve is so far over the top it borders on unusable. (isnt the "+" model the one with an extra gain stage?)

try plugging directly into the head without any effects or gates to rule out those devices. then try swapping tubes maybe there is a tube fault somewhere.

As for the bias mod, i wouldn't play a 6505 without it, though warming up the tone and getting the bias out of crossover distortion might actually take away some of the qualities I think draw people to these amps. It will be less harsh distortion, a smoother more complex tone, a little less dry sounding.

In fact Id go so far as to say if that's not EXACTLY what you're looking to get out of a 5150 type amp, then there is no other point in playing one. IMO the harsh,brittle "crunch" those amps are known for is the only selling point.

I have a pic of the completed bias mod but cant find the instructions at this time... basically a resistor and a pot placed across and existing capacitor.


thanx for posting the pic!...all of the other 6505+'s i have played sounded realy close to the sound i am looking for...but as i mentioned it was always with someone elses gear...none of them sounded flat to me...well except for this one...and as far as useable gain goes....this one dont have enough!!
i have already tried deleting everything in the signal chain both pre/post...
 
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