How to retube a laney irt60 head?

[Dawylde]

Hi! I know this is a noob question, but I'm a little scared on doing this, i have read one can get an electric shock, so i want to be sure on how the retubing should be done on a laney irt60 head. The manual isnt specific and I havent found anything convincing on the internet.
I have a tube kit for this amp, tung sol 2 6l6 and 4 12ax7.

Please someone with experience on these amps and some patience to explain. Thank you in advance!

 

[Mike]

Unplug the amp from the wall and remove the power chord from the back of it. Let it sit for a little while (half hour to an hour). If I recall, you have to take off both the front and back grille covers to reach all of the tubes. There's like 6 screws in each, take them all out and remove the grilles.

Firmly grasp the tube you want to replace and pull up. You may need two hands to do so since those tubes lock in pretty tight. Line up the pin holes and put in the new tube. Make sure it's pushed in all the way. You'll be able to tell when it won't go down anymore. For the power tubes, you'll have to use two fingers to spread the metal clamps while you use the other hand to remove and insert the replacement power tubes.

If you're having trouble seeing the pins, what I do sometimes is take a pic with my cell phone from straight overhead down into the empty tube socket. The phone pic shows me the direction and orientation of the socket and I can get a better feel for how I'm lining up the pins.

This is what I'm referring to when I say tube socket:

Wear rubber shoes if your worried, but you're not going to get shocked replacing the tubes in the Laney don't worry.

 

[cGoEcYk]

It should be pretty straightforward to swap the tubes. Make sure to unplug amp. That should help with the electrical shock.

Beyond that carefully pull out the new tubes. You can wiggle them a little.

Power tubes just drop in. There should be a guide on the base of the tube near the sockets so that it locks into the right position.

Preamp tubes if you got a specially selected set you may want to review what position each tube should go into, usually notated as V1, V2, V3, etc. The "V" sequence begins with V1 closest to the instrument jack on the amp. Preamp tubes you might rotate a bit until the pins line up in the slots then press them in.

 

[Dawylde]

Wow thank you for answering. I feel a bit more confident on doing it. So I will able to see the v1, v2... Positions? What about the phase inverter tube, what is that? Does that go on the v1 position? Thanks!

 

[maggotspawn]

You should bias the power tubes. Google is your friend here.

 

[Mike]

You should bias the power tubes. Google is your friend here.

Setting the bias is something you may want to leave to a professional. If you're worried about getting shocked doing a tube swap, then setting the bias is something you should outsource.

That said, you don't necessarily need to rebias the Laney after a power tube swap. It is a good idea because it's meant to get the best performance and longevity out of your new power tubes, but the IRT series are cathode biased, so they'll operate just fine with just about any 6L6 you pop in there.

Wow thank you for answering. I feel a bit more confident on doing it. So I will able to see the v1, v2... Positions? What about the phase inverter tube, what is that? Does that go on the v1 position? Thanks!

Yes you'll be able to see them, no they won't be labeled in such a user friendly manner that each socket says what it is. Refer to pages 16 and 17 of your manual. It's the schematic telling you which slot is which: http://www.laney.co.uk/wp-content/uploads/2016/01/47a9b94661fc52d2f439ec7d75339b48.pdf

The phase inverter tube is the last tube in the chain. It's the small tube that is separated from the other small tubes. It basically takes your whole chain of preamp tube output/gain/tone/eq that you've created by tweaking the knobs, and passes it over to the power section for amplification and output to the speaker cab.

Phase inverter tube is not V1, it's V4. V1 is your input gain stage tube. It's the tube furthest left, closest to the input jack. Usually, and in the case of the Ironheart 60, the most important preamp tube. You want something high grade here. Basically a selected tube that is graded to be low noise. Something like a Ruby 12AX7 HG+, or a Tung Sol 12AX7 Reissue is great for the V1 spot.

 

[skmanga]

http://www.sevenstring.org/forum/showpost.php?p=4614945&postcount=530

this might help.
info on biasing the ironheart 30 watt combo which is very similar.

 

[Dawylde]

Ok thank you very much, that makes it a lot more clear! Where I got a bit lost is at the biasing of the amp, but you say I should not worry about doing that, the amp will work just fine if i pop in the new 6l6, right?
I saw the diagram skmanga posted, that is something more technical i guess, i would be needing a tool for this right?
On the back of the amp there is a bias switch for 6l6 or el34, im guessing if i did swap for el34 then i would definitely need to do the biasing?
All I want to be sure of is if my amp will work fine if I just swap in the tubes without doing the biasing (which still im not sure what exactly that is) im sure i can do that by myself. But the biasing, im not sure about, will there be a point where it will need to be done?

Im sorry about all the questions, I just want to get it right! Thank you so much for your answers!

 

[Mike]

Like I said, leave biasing to a professional. It involves taking more of the amp apart, getting into the more dangerous aspect of the electronics inter-workings and messing with adjusting the bias pot. If you don't know what you're doing, (which you don't seem to), then you shouldn't be in there messing with tweaking the voltage of anything.

It'll work just fine if you just put the tung sol 6L6's in and just play it. You're not going to blow the amp up or instantly destroy the tubes. The worst thing that might happen is if the bias is not optimally set (Which like 99% of amps new from the store aren't set right anyways) is your tubes might not last as long as they could. So maybe instead of having to replace them every 2 years, you end up having to put in a new set in a year and 6 months. Just make sure the switch on the back is set to 6L6, which it already should be and you'll be good to go. If you do decide you want to use EL34's, according to Laney all you need to do is switch the switch and it'll operate just fine with EL34's.

 

[Dawylde]

Thank you so much for your answers!

 

[skmanga]

Switching from 6l6's which come stock to el34's will involve a proper bias.
Swapping for a different set of 6l6's will work fine without a re-bias, both my friend with his 60 watt ironheart head, and I with my 30 watt ironheart combo have confirmed this.
The amp wont be at its optimal state though, and will operate more efficiently and sound better with a proper bias, though it will operate fine without a bias.

I was about ready to kick this amp to the curb, but 2 things I did that changed my mind completely were adding an attenuator and biasing the amp properly. Biasing had the greater effect.

Some other tips I would recommend are finding some good speakers, in your case with a head I would maybe try finding 2 different speakers that compliment each other nicely.
Preamp tube wise, in my opinion the amp comes with 1 good tube which is the TAD.
I would put that TAD in V1 and leave it there till you get something that's better which in my opinion is a Highgrade TAD. I've had success with gold lions and ehx's. So far my fave combo is a a highgrade TAD in V1, the stock TAD in V2 and an EHX in V3.
You've got an extra gain stage to play with it seems being that you have the 60 watt head. That just means more tone
My tip would be TAD in v1 and an EHX in v4, the rest is up to you!!
Tried a single tung sol early on and didn't like it, maybe ill try it again at some point.

Good luck!!

 

[Dawylde]

Switching from 6l6's which come stock to el34's will involve a proper bias.
Swapping for a different set of 6l6's will work fine without a re-bias, both my friend with his 60 watt ironheart head, and I with my 30 watt ironheart combo have confirmed this.
The amp wont be at its optimal state though, and will operate more efficiently and sound better with a proper bias, though it will operate fine without a bias.

I was about ready to kick this amp to the curb, but 2 things I did that changed my mind completely were adding an attenuator and biasing the amp properly. Biasing had the greater effect.

Some other tips I would recommend are finding some good speakers, in your case with a head I would maybe try finding 2 different speakers that compliment each other nicely.
Preamp tube wise, in my opinion the amp comes with 1 good tube which is the TAD.
I would put that TAD in V1 and leave it there till you get something that's better which in my opinion is a Highgrade TAD. I've had success with gold lions and ehx's. So far my fave combo is a a highgrade TAD in V1, the stock TAD in V2 and an EHX in V3.
You've got an extra gain stage to play with it seems being that you have the 60 watt head. That just means more tone
My tip would be TAD in v1 and an EHX in v4, the rest is up to you!!
Tried a single tung sol early on and didn't like it, maybe ill try it again at some point.

Good luck!!

Thanks for the tip bro! Stock tubes on mine make it sound great, im running my amp through a mesa 2x12 and I have found this cab to meet my expectations, sounds really nice, clear sounding and loud as hell! Best of all the cab i can carry anywhere and fits in my car hahaha!

 

[Dawylde]

I contacted Laney through their website and asked them about biasing the laney irt60H.

This is the exact answer i got from service support from someone who works at Laneys workshop:

"The IRT60H is not cathode biased and will require the bias checking and adjusting if necessary when replacing output tubes."

"The IRT60H should be re-biased when replacing output tubes. No two set of tubes are the same, so a check of the bias is recommended.
This makes sure that the amp runs at optimum performance for the tubes fitted."

For optimum use I think doing the bias is definitely worth it. I will have to do my research to learn more about this. Any links on biasing or videos you guys can share are very welcome! Thanks!

 

[jarnozz]

check some video's on youtube! long story short
- power off
- disconnect from wall outlet
- remove tubes
- new tubes in
- calculate bias
- power on
- check and adjust bias
- done

takes me like 5 minutes max

 

[Dawylde]

check some video's on youtube! long story short
- power off
- disconnect from wall outlet
- remove tubes
- new tubes in
- calculate bias
- power on
- check and adjust bias
- done

takes me like 5 minutes max

Have you ever done it on a Laney irt60H? I cant find anything for this amp.

 

[jarnozz]

Have you ever done it on a Laney irt60H? I cant find anything for this amp.

Nope. But I build amplifiers and this is my routine for changing tubes! It has worked on all amps I've retubed. Marshalls, vox, peavey, mesa and fenders