Re-Tube Mesa Dual Rectifier

[painkiller]

Hi

I need to re-tube my Mesa Dual recti Rev. G.
I want to do it with Mesa branded Tubes but they are not available here in Europe.
Any recommendations?
thx

 

[domct203]

JJ’s are always a good bet. Just make sure your power tubes are selected to run in a Mesa Dual Recto.

 

[VisaL]

JJ. And have it biased. I dont think any tube will bias properly in dual. Mine was running 19% of the max dissipation on stock setting. Now it is quite a bit less fizzy.

 

[bandit2013]

The JJ ECC83s are the Mesa 12AX7 tubes. It will be difficult to get the Mesa STR440 as they are out of production. STR445 are the JJ 6L6GC tubes. Indicate the amp you are using the power tubes with, most vendors can match the tubes to the amp. Rectifier tubes, I assume the Rev G is using the 5U4GB, just about any brand, will work, JJ has those too. I believe the Mesa version are the Electro Harmonix brand.

Just a note: it is difficult to get the Mesa branded tubes here in the USA as well. Times are tough and getting replacement parts can be difficult.

 

[JustPassingThrough]

I run mine with Tung Sols in every position. You don't need Mesa tubes, unless you have a warranty you're concerned about keeping.

You don't need Mesa tubes.

 

[domct203]

Yes if warranty is not an issue you don’t need Mesa branded tubes.

Be cautious with New Sensor made tubes in cathode follower positions, including the Tung Sol RI, Sovtek, Electro-Harmonics, and possibly the Mullard RI, they can’t take the higher voltages used in cathode follower circuits.

https://boogieforum.com/threads/did-you-get-the-memo.25102/#post-186780
https://www.thegearpage.net/board/i...-in-cathode-follower-position-of-amps.695357/
https://www.lespaulforum.com/index....reissue-in-a-cathode-follower-circuit.170339/

 

[user 21540]

Eurotubes sell full JJ kits for Mesa amps with the power tubes in the right bias range:
https://www.eurotubes.com/store/pc/Retube™-Kits-for-Mesa-c10.htm

 

[cgscotto]

As others have said, the JJ’s are a good choice for the rectifier series. I just retubed my Triple with JJ’s from Amplified Parts. You just tell what amp the tubes will go into, and they will choose an appropriate PC value. The set they sent me were rated 35, which works really well in the triple. Finally, the Mesa 445 tubes on their website are JJ’s, and they recommend the 445s for Rectifier amps.

 

[VisaL]

Has anyone measured bias with those sets that are advertized as having right bias range? The set i have is supposed to be for mesa, but i dont think 19% is correct bias range. Though that’s propably how ’mesa’ tubes bias in dual.. Mine are not from eurotubes but one of those well regarded vendors who relabels oem tubes.

 

[painkiller]

Awsome...thanks to all for help.
Could someone explain me the meaning of the rectifier rubes?
I use Silicon diodes and Bold, do i need them in this case?
I have them pulled out and it works...
thanks

 

[tbonesullivan]

Awsome...thanks to all for help.
Could someone explain me the meaning of the rectifier rubes?
I use Silicon diodes and Bold, do i need them in this case?
I have them pulled out and it works...
thanks

If you are only using the diodes, you do not need them installed in the amp at all.

 

[cgscotto]

The rectifier tubes convert an AC line current to DC. The diode circuit does the same thing. However, rectifier tubes are slower than the diodes. With rectifier tubes, playing at high volume can result in the amp instantaneously wanting more current than the rectifier tubes can supply so you get a lag and a momentary drop in current ant voltage, which most musicians call sag. Silicon diodes do not cause a lag between demand and supply, so the response is immediate, which is why Mesa says the diodes are bold and punchy.

Personally, I don't think I have ever had my triple loud enough to experience the sag. I live in the diodes setting.

 

[tbonesullivan]

Personally, I don't think I have ever had my triple loud enough to experience the sag. I live in the diodes setting.

There is still a difference, as I believe the valve rectifier may operate at a slightly lower voltage than the diodes normally. There is definitely a change in the feel and sound of the attacks when I switch to tube rectifiers on my Stiletto, which I can do right on the front panel.