JJ 12ax7 and 12au7 tubes

[tman]

I just ordered these and they didnt come yet but has anybody used these before? Was wondering the difference in tone with these two different kinds of tubes? And are they good reliable tubes. I got them because they were marked down and needed some extras. Im still new to tubes and have used EH 12ax7's and Tungsol's and like those two very much. Thanks

 

[Funkfingers]

Re: JJ 12ax7 and 12au7 tubes

The principle difference between 12AX7 and 12AU7 is the degree of gain that each offers. (The AX7 produces higher gain than the AU7.)

 

[zzmoore]

Re: JJ 12ax7 and 12au7 tubes

The principle difference between 12AX7 and 12AU7 is the degree of gain that each offers. (The AX7 produces higher gain than the AU7.)

^^^^^^^ That pretty much sums it up.
But yeah, there will be a Huge Difference in gain, and that WILL affect tone.
Not exactly a real world comparison.....two different things.
You will soon know for yourself though.
good luck

 

[tman]

Re: JJ 12ax7 and 12au7 tubes

Ok what about the diff between the JJ's 12ax7's and the tunsol and EH tubes??

 

[zzmoore]

Re: JJ 12ax7 and 12au7 tubes

Ok what about the diff between the JJ's 12ax7's and the tunsol and EH tubes??

You know what, I am all for discussion, and sharing experiences, but ..... You frequently get all kinds of different opinions, and who cares what I think anyway. Tubes Do/Can sound different in different amps, and at different volumes.
In the end, you just need to buy a few (just like you did )and see what you hear.
Fortunately, modern day tubes are fairly inexpensive.....and a tube that may not sound "good" now, will find its home later.

AND, keep in mind, people always have a bad experience.
"I bought three XYZ tubes, and they all failed within one hour. Never buying that brand again...they are junk".
It is easy to think that, but you could buy another hundred in a row, and not have one failure. Three out of Thousands means absolutely nothing.
One of the most important things to consider (when buying new tubes) is how much burn time the seller does. A seller that burns tubes for 24 hours, may very well cull 10-20 of his stock. That might make his tubes cost a little more, but YOUR failure rate will go Way Down.
good luck

 

[Demanic]

Re: JJ 12ax7 and 12au7 tubes

I love JJ's. They also make a tube that has both a 12AX7 side along with a 12AU7 side.

 

[jeremy]

Re: JJ 12ax7 and 12au7 tubes

so each preamp tube is actually two gain stages (assuming you know this) so when you switch from a 12ax7 with a typical gain of 100 on each side to a 12au7 with a gain of 20 on each side you lose a ton of gain. not a bad thing necessarily but its a big difference

 

[GilmourD]

Re: JJ 12ax7 and 12au7 tubes

The funny thing about 12AU7s... Because tubes are a whole lot more complicated than just gain levels...

You can build a power amp using 12AU7s. A single 12AU7 in Class AB will output about a watt. I've toyed with the idea of building a Mini Plexi, basically substituting each side of a 12AU7 for each EL34 in a 1959 (of course wired for cathode bias and however else it would need to be set up).

 

[Demanic]

Re: JJ 12ax7 and 12au7 tubes

so each preamp tube is actually two gain stages (assuming you know this) so when you switch from a 12ax7 with a typical gain of 100 on each side to a 12au7 with a gain of 20 on each side you lose a ton of gain. not a bad thing necessarily but its a big difference

With the JJ's ECC832, the first stage is a 12AX7 and the second is the 12AU7. I have one in the #2 spot in my Picovalve, paired with JJ's ECC83MG, which is a medium gain 12AX7. The combination seems to give me a bit more headroom and a bit tighter response when using dirt pedals.

 

[tman]

Re: JJ 12ax7 and 12au7 tubes

Yeah I got a behringer vintage monster tube OD pedal and it uses a tube in the pedal kinda like a preamp pedal and it sounds awesome with the JJ 12 ax7 and the 12au7 they have a less gainy nicer smooth sound IMO. I also like the EH 12 ax7 for a little hotter gain. I use it in the power amp input on the back of my Peavey bandit "silver strip" with an upgraded cv-75 Eminence speaker and it acts as the amps preamp bypassing its own preamp and I think it sounds awesome in my bandit. I basically turned my bandit into a hybrid lol. But yes the JJ's and EH both sound good in that pedal. And another hybrid amp I have also. I havent tried a Tung sol yet but thats next.

 

[GuitarStv]

Re: JJ 12ax7 and 12au7 tubes

I like JJs. They sound good in the amps I've run them in and can be had cheaper than EHX stuff.

 

[GilmourD]

Re: JJ 12ax7 and 12au7 tubes

I like JJs. They sound good in the amps I've run them in and can be had cheaper than EHX stuff.

It depends on the amp. I find JJ ECC83S's kinda dark in Marshall type preamp but they work well in Fender type.

Sent from my Moto X 2014 using Tapatalk

 

[GuitarStv]

Re: JJ 12ax7 and 12au7 tubes

It depends on the amp. I find JJ ECC83S's kinda dark in Marshall type preamp but they work well in Fender type.

Sent from my Moto X 2014 using Tapatalk

Fair enough, I've tried them in two fender style amps . . . one based on the bassman circuit and one based on the deluxe reverb circuit.