34's in a Twin Jet = EVIL

[steve_k]

Dammit.....is all I can say. I am still stunned and shocked at the difference this made in the amp

It was already wicked with the 88's, but the 34's get out the glassiness, controls the mids better and makes the bottom end really stand out. Thanks to those that turned me on to this amp and for Zack making the recommendation. The amp is so easy to dial in now. Tried it with a cab full of V30's and one with H30's and one with Greenies and hell they all blaze. There is definitely more effective controlling of all the EQ with the 34's too.

And God bless Reinhold for setting the amp up with the bias resistors the way he did. All you got to do is clip the 22k piggy-backed resistor off and leave the 33k. Set the bias adjust about half way. I had a new quad of SED Winged C's with the PC @ 42. Kicked on the bias rite and it was setting on 29mA. With 110VAC input, my PV is reading 500V. A minor adjustment up to 35mA and it was there. Click, click, boom.

I can't imagine going back to 88's. But, a person could easily mount a two way switch on the back of the chassis to switch from 34's to 88's without having to muck about. 20K ohm resistors on 88 side and 33 on the 34 side and you are there.

Both channels come alive and really fill a room set up this way.


Steve

 

[Mailman1971]

It is all TRUE........

Your a MAIN SOURCE OF GAS around here!!

Hey Brother.......can you spare a Beano?

Amp sounds like it just slays....

Danno

 

[ttosh]

Just great..... Just freaking great!!!!

 

[se7en]

YES! Glad to hear it was a great success. I, too am running SED's in mine...When I first made the change, I was worried I'd be losing something to gain the benefits of the 34's, but I have no regrets...I think anyone who sold this amp would have really dug it with 34's...organic, rich, tight and more open than past Ubers...what's not to like?

 

[rlord1974]

All I have to say is, based on the amps Steve's unloading in the Classified section right now, I get the impression that he is the kind of guy I would have liked being a "wingman" for back in College. Feasting on his "scraps" would NOT be a bad deal!

 

[Shiny_Surface]

YES! Glad to hear it was a great success.

Look what you started Zack.

 

[se7en]

YES! Glad to hear it was a great success.

Look what you started Zack.

...So, when are we converting your Twin Jet?

 

[ttosh]

All I have to say is, based on the amps Steve's unloading in the Classified section right now, I get the impression that he is the kind of guy I would have liked being a "wingman" for back in College. Feasting on his "scraps" would NOT be a bad deal!

 

[Shiny_Surface]

YES! Glad to hear it was a great success.

Look what you started Zack.

...So, when are we converting your Twin Jet?

I have the tubes, I've just been lazy maybe this weekend.

Isn't it funny how it's popular to convert the Rev 2/Blue's to KT88's, just the opposite.

 

[ttosh]

YES! Glad to hear it was a great success. I, too am running SED's in mine...When I first made the change, I was worried I'd be losing something to gain the benefits of the 34's, but I have no regrets...I think anyone who sold this amp would have really dug it with 34's...organic, rich, tight and more open than past Ubers...what's not to like?

If I knew how to do this myself and I could easily swap back I would give this a try. Outside of tube changes and bias with external points I stop there.... I would love to hear the difference however, as I love it the way it is, if it could actually get better I would be floored bigtime.

 

[se7en]

YES! Glad to hear it was a great success.

Look what you started Zack.

...So, when are we converting your Twin Jet?

I have the tubes, I've just been lazy maybe this weekend.

Isn't it funny how it's popular to convert the Rev 2/Blue's to KT88's, just the opposite.

Cool. Give me a call if you decide you're gonna do it, Tom.

I think the reason why the 88's were a popular replacement for past iterations is because they were more compressed. With the TJ, the circuit is tighter and more open. No need. For the price these go for, you can't beat it.

 

[se7en]

YES! Glad to hear it was a great success. I, too am running SED's in mine...When I first made the change, I was worried I'd be losing something to gain the benefits of the 34's, but I have no regrets...I think anyone who sold this amp would have really dug it with 34's...organic, rich, tight and more open than past Ubers...what's not to like?

If I knew how to do this myself and I could easily swap back I would give this a try. Outside of tube changes and bias with external points I stop there.... I would love to hear the difference however, as I love it the way it is, if it could actually get better I would be floored bigtime.

It's not hard to do, as long as you have a bias tool and 30 minutes. Shoot me a PM if you decide to make the change.

 

[TheMagicEight]

YES! Glad to hear it was a great success. I, too am running SED's in mine...When I first made the change, I was worried I'd be losing something to gain the benefits of the 34's, but I have no regrets...I think anyone who sold this amp would have really dug it with 34's...organic, rich, tight and more open than past Ubers...what's not to like?

+1

Blows the KT88s right out of the water!

 

[steve_k]

I gotta try this!

Easy to do. Get you a set of SED Winged C's or if you are a JJ guy, E34L's. Make sure the quad is matched and a PC in the high 30's to low 40's. The quad of SED's I used was a 42.

1. In the chassis, adjacent the bias screw, look for two piggy backed resistors at R402. Next to the fuse holders.

2. Take some small wire snips and clip the resistor off near the body. Leave the tails in case you want to go back with another.

3. As delivered, it has a 33K on bottom and a 22K on top. This gives an Req-13.2 ohm for the 88's.

4. Flip the chassis back over. Set the bias adjust about mid range.

5. Swap the tubes out. Hook up a speaker/power. Is using a Bias rite, set it up.

6. Turn it on, and you should see about 30mA bias without doing anything. I measure my PV @ 500V. Then biased up to 35mA.

This takes no more than 10 minutes or so and you are ready to go. Someone questioned why Bogner piggybacks the bias resistors. It so you can clip the top one off, which is parallel, not series, and be able to use 34's fairly easy. It would be easy to rig a switch to the chassis wired straight to the PC and remove that other resistor and put the resistors on the switch. You could then change between 34's, 88's or whatever you wanted to do.

Steve

 

[ttosh]

Another thanks for the detailed instructions. I may give this a try in the near future. I want to spend more time with the KT88's first as I am really digging them at the moment. This would give me more time to also get more used to the 88's overall tone for when I make the switch for comparison.

I gotta try this!

Easy to do. Get you a set of SED Winged C's or if you are a JJ guy, E34L's. Make sure the quad is matched and a PC in the high 30's to low 40's. The quad of SED's I used was a 42.

1. In the chassis, adjacent the bias screw, look for two piggy backed resistors at R402. Next to the fuse holders.

2. Take some small wire snips and clip the resistor off near the body. Leave the tails in case you want to go back with another.

3. As delivered, it has a 33K on bottom and a 22K on top. This gives an Req-13.2 ohm for the 88's.

4. Flip the chassis back over. Set the bias adjust about mid range.

5. Swap the tubes out. Hook up a speaker/power. Is using a Bias rite, set it up.

6. Turn it on, and you should see about 30mA bias without doing anything. I measure my PV @ 500V. Then biased up to 35mA.

This takes no more than 10 minutes or so and you are ready to go. Someone questioned why Bogner piggybacks the bias resistors. It so you can clip the top one off, which is parallel, not series, and be able to use 34's fairly easy. It would be easy to rig a switch to the chassis wired straight to the PC and remove that other resistor and put the resistors on the switch. You could then change between 34's, 88's or whatever you wanted to do.

Steve

 

[steve_k]

Did yours ship with Sovtek's Tim?

Another thanks for the detailed instructions. I may give this a try in the near future. I want to spend more time with the KT88's first as I am really digging them at the moment. This would give me more time to also get more used to the 88's overall tone for when I make the switch for comparison.

I gotta try this!

Easy to do. Get you a set of SED Winged C's or if you are a JJ guy, E34L's. Make sure the quad is matched and a PC in the high 30's to low 40's. The quad of SED's I used was a 42.

1. In the chassis, adjacent the bias screw, look for two piggy backed resistors at R402. Next to the fuse holders.

2. Take some small wire snips and clip the resistor off near the body. Leave the tails in case you want to go back with another.

3. As delivered, it has a 33K on bottom and a 22K on top. This gives an Req-13.2 ohm for the 88's.

4. Flip the chassis back over. Set the bias adjust about mid range.

5. Swap the tubes out. Hook up a speaker/power. Is using a Bias rite, set it up.

6. Turn it on, and you should see about 30mA bias without doing anything. I measure my PV @ 500V. Then biased up to 35mA.

This takes no more than 10 minutes or so and you are ready to go. Someone questioned why Bogner piggybacks the bias resistors. It so you can clip the top one off, which is parallel, not series, and be able to use 34's fairly easy. It would be easy to rig a switch to the chassis wired straight to the PC and remove that other resistor and put the resistors on the switch. You could then change between 34's, 88's or whatever you wanted to do.

Steve

 

[ttosh]

Yes 4 Sovtek KT88's and all chinese preamp tubes. I have some TAD Select preamp tubes I may give a try, any suggestions?

Did yours ship with Sovtek's Tim?

Another thanks for the detailed instructions. I may give this a try in the near future. I want to spend more time with the KT88's first as I am really digging them at the moment. This would give me more time to also get more used to the 88's overall tone for when I make the switch for comparison.

I gotta try this!

Easy to do. Get you a set of SED Winged C's or if you are a JJ guy, E34L's. Make sure the quad is matched and a PC in the high 30's to low 40's. The quad of SED's I used was a 42.

1. In the chassis, adjacent the bias screw, look for two piggy backed resistors at R402. Next to the fuse holders.

2. Take some small wire snips and clip the resistor off near the body. Leave the tails in case you want to go back with another.

3. As delivered, it has a 33K on bottom and a 22K on top. This gives an Req-13.2 ohm for the 88's.

4. Flip the chassis back over. Set the bias adjust about mid range.

5. Swap the tubes out. Hook up a speaker/power. Is using a Bias rite, set it up.

6. Turn it on, and you should see about 30mA bias without doing anything. I measure my PV @ 500V. Then biased up to 35mA.

This takes no more than 10 minutes or so and you are ready to go. Someone questioned why Bogner piggybacks the bias resistors. It so you can clip the top one off, which is parallel, not series, and be able to use 34's fairly easy. It would be easy to rig a switch to the chassis wired straight to the PC and remove that other resistor and put the resistors on the switch. You could then change between 34's, 88's or whatever you wanted to do.

Steve

 

[steve_k]

If you want to stay with the 88's, I would try JJ's. Not a huge all around JJ fan, but their 88's are different. I messed around a bit with preamp tubes and came up with:

V1-Sovtek LPS
V2-Ruby HG+
V3-Tung Sol
V4-Ruby 12AX7 Select
V5-Chinese 9
V6-JJ 12AX7 Gold Plated Balanced

Stayed with the same after the SED Winged C 34's went in.

Steve

Yes 4 Sovtek KT88's and all chinese preamp tubes. I have some TAD Select preamp tubes I may give a try, any suggestions?

Did yours ship with Sovtek's Tim?

Another thanks for the detailed instructions. I may give this a try in the near future. I want to spend more time with the KT88's first as I am really digging them at the moment. This would give me more time to also get more used to the 88's overall tone for when I make the switch for comparison.

I gotta try this!

Easy to do. Get you a set of SED Winged C's or if you are a JJ guy, E34L's. Make sure the quad is matched and a PC in the high 30's to low 40's. The quad of SED's I used was a 42.

1. In the chassis, adjacent the bias screw, look for two piggy backed resistors at R402. Next to the fuse holders.

2. Take some small wire snips and clip the resistor off near the body. Leave the tails in case you want to go back with another.

3. As delivered, it has a 33K on bottom and a 22K on top. This gives an Req-13.2 ohm for the 88's.

4. Flip the chassis back over. Set the bias adjust about mid range.

5. Swap the tubes out. Hook up a speaker/power. Is using a Bias rite, set it up.

6. Turn it on, and you should see about 30mA bias without doing anything. I measure my PV @ 500V. Then biased up to 35mA.

This takes no more than 10 minutes or so and you are ready to go. Someone questioned why Bogner piggybacks the bias resistors. It so you can clip the top one off, which is parallel, not series, and be able to use 34's fairly easy. It would be easy to rig a switch to the chassis wired straight to the PC and remove that other resistor and put the resistors on the switch. You could then change between 34's, 88's or whatever you wanted to do.

Steve

 

[richedie]

How versatile do you find the amp with El34s? How different is it from the 20th Shiva which I have. I set mine up with EL34s but I like mine biased at 36ma, sounds and feels better than 29ma in my opinion.

I am thinking of getting another Bogner and the Twin is on my list. I typically liked having a pristine clean channel but it also gets old and wold be nice having an amp with a semi dirty clean channel because I find in a lot of live situations a little dirt helps and sounds more natural than going pristine clean to dirty and back! So, if the amp is versatile, I might consider finindg a used Twin. I just love Bogners.

Thought about looking at a used Fryette SigX, Diezel of some sort, but too expensive...seems the Uber or Twin might be a nice fit to my collection of 2011 Reborn Dual Rec and EL34 2010 20th Shiva.

How is the master on the TJ? Can it sound as good as something like a 20th Shiva at low volumes?

I would have considered the 20th XTC but too expensive. I see Jets going used for less. And to think I was going to buy an Axe FX! LOL. Believe it or not, also looking at the Goldfinger.

 

[leib10]

Any chance of a recording of the EL34 Twin Jet?