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Product 210390

THD YJSD Yellow Jacket Standard Duet Adapter   

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The YLSD is an adapter that permits the use of an EL84 power tube in place of a 6L6, EL34, or 6550 in grid-bias amps. There are no adjustments to mak...Read More

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OVERVIEW

Converts your amp to Class A EL84 operation.

The YLSD is an adapter that permits the use of an EL84 power tube in place of a 6L6, EL34, or 6550 in grid-bias amps. There are no adjustments to make and no modifications necessary. You simply plug the Yellow Jacket into the amp's output tube sockets, plug the provided EL84s into the Yellow Jacket, turn on the amp, and play.

THD's Yellow Jacket converters not only rearrange the pin locations of the tubes, but also provide the necessary current limiting on the screens and cathode as well as blocking the amplifier's grid-bias voltage, configuring the EL84 in a Class-A, self-adjusting cathode-bias circuit.

When the Yellow Jacket Converters are installed in larger amplifiers intended for 6L6s or EL34 output tubes, the high plate and screen voltages are reduced as well as current limited to protect the EL84 and to drop output power. When a pair of Yellow Jacket are used in a Marshall 50W or similar amplifier, the overall power drops to about 20W and takes on more of the character of an old Vox AC30. The distortion is smoother and more even and the output is both substantially reduced and more compressed due to the Class-A nature of the Yellow Jackets. In a 100W amp like a Twin Reverb or Marshall 100, either 2 or 4 Yellow Jackets can be used. If only 2 are used and the other 2 sockets are left empty, the output is dropped to about 20 watts. With 4 in place, the amp puts out about 40W and takes on a whole new warmth and richness.

Will they hurt your amp? No! Yellow Jacket converters are safe for all amplifiers and transformers. As all Yellow Jacket converters internally regulates voltage and current they put no extra strain on amplifiers' power and output transformers or internal components. Using the Yellow Jacket in higher powered amplifiers actually reduces the strain on the transformers and internal components because it reduces the overall wattage of the system. Furthermore, the heater (or filament) current of the EL84 is lower than that of the 6L6, EL34 or 7591, so the Yellow Jacket will reduce the strain on the filament windings of the power transformer as well.

FEATURES
  • Use an EL84 in place of a 6L6, EL34, or 6550 in grid-bias amps
Reviews
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Review Snapshot

by PowerReviews
 
4.8

(based on 13 reviews)

Ratings Distribution

  • 5 Stars

     

    (11)

  • 4 Stars

     

    (1)

  • 3 Stars

     

    (1)

  • 2 Stars

     

    (0)

  • 1 Stars

     

    (0)

Most Liked Positive Review

 

Do You Have The Time To Listen To Me Whine

For those of you who have put these in your Hot Rod combos and are saying the tubes don't seem to last very long---What you have is what I call a...Read complete review

For those of you who have put these in your Hot Rod combos and are saying the tubes don't seem to last very long---What you have is what I call a "Combat Zone" amp. The tubes are in such close proximity to the speaker that the tubes are getting beaten to death. This a battle that will NEVER be won by the tubes. I learned this lesson back in the sixties when AC 30's were all the rage but were the most unreliable things out there. I guess that's why so many of us sold our combos and bought seperate head and cabinet amps Now here's the bottom line--I have put them in Hot Rods and they do sound great and give you a different tonal coloration than the 6L6's and a sizzle that you can't get from a 6L6 but if you gig on a regular basis have some spare 84's--You'll need them. It's like everything else: Never gig without a backup! Always have spare tubes,fuses,instrument cables,strings and blah blah blah!!! It's not cheap doing what we do!
They perform exactly as advertised. If you have any questions or problems with them you can email or call the folks at THD and they respond to their emails quickly and they actually answer the phones with a living breathing human being. You won't get some ROBOT telling you "press 1 for this---press 2 for that". I called them once and actually talked to Andy Marshall who is the owner of the company! He was the one who answered the phone on the 2nd ring. The best part was we talked for a very long time about tube swapping. He turned me on to some tubes I hadn't thought about using and actually said he would try some combinations I have tried. It doesn't get any better than that in the world of customer service!!!
They're well built and I have had zero problems with them. The JJ's they came with are robust and will give you an idea of what EL 84's sound like but don't expect them to sound like a pair of Amperex Bugle Boys (which I am currently running in mine). Now here is where I am going to start addressing some of the gripes in the reviews below. For the person who said they made a crackling sound until he pushed them in tight but they started doing it again: Deoxidize the tube sockets and the pins on your tubes EVERY TIME you install them!!! The least little oxidation will give you an intermittent signal. I have people bring me amps all the time saying "The tubes were crackling so I put new ones in and they're doing the same thing". HEY PEOPLE---WAKE UP!!! Tube amps need maintenance just like your car. There's a product called Caig Deoxit. They sell it right here at Musician's Friend. If you buy new tubes then buy a can of this too!
For the price point they're a great deal. They're a lot cheaper than buying a Vox AC 30 or some other EL 84 equipped amp. Will they make your Hot Rod Deville sound like an AC 30?--NO!--Will they lower the volume of your amp to where you can play it in the bedroom and not wake the kids?--NO!--For those of you who think a 50 Watt amp is half as loud as a 100 watt amp--Wrong Again!--A 50 watt versus a 100 watt is only 3 decibels less. All you lose with a 50 watter is 3 DB of headroom.
If you want to play in the bedroom and not wake mommy buy an attenuator.

VS

Most Liked Negative Review

 

not what I had hoped for

If you want to change the tone and distortion character of your amp then these *might* be for you. I was mostly hoping to reduce volume on amps that already have great tone...Read complete review

If you want to change the tone and distortion character of your amp then these *might* be for you. I was mostly hoping to reduce volume on amps that already have great tone but are very loud (I tried them in my Marshall and HiWatt amps). They don't really reduce volume much, a pair of EL84s can still be quite loud. Also they are tall, for example will not fit in my Fender Showman. Using these with the original EL-34 tubes in my 4 tube amp (Marshall) was probably the most interesting thing for me, it added some nice complexity to the tone. But, my local tube amp guru tells me he wouldn't trust them in a valuable vintage amp. Consider the cost and the fact that they essentially are not returnable here... not sure I would buy again.

Reviewed by 13 customers

Displaying reviews 1-10

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(2 of 2 customers found this review helpful)

 
5.0

Do You Have The Time To Listen To Me Whine

By Duke

from Athens, Texas

For those of you who have put these in your Hot Rod combos and are saying the tubes don't seem to last very long---What you have is what I call a "Combat Zone" amp. The tubes are in such close proximity to the speaker that the tubes are getting beaten to death. This a battle that will NEVER be won by the tubes. I learned this lesson back in the sixties when AC 30's were all the rage but were the most unreliable things out there. I guess that's why so many of us sold our combos and bought seperate head and cabinet amps Now here's the bottom line--I have put them in Hot Rods and they do sound great and give you a different tonal coloration than the 6L6's and a sizzle that you can't get from a 6L6 but if you gig on a regular basis have some spare 84's--You'll need them. It's like everything else: Never gig without a backup! Always have spare tubes,fuses,instrument cables,strings and blah blah blah!!! It's not cheap doing what we do!
They perform exactly as advertised. If you have any questions or problems with them you can email or call the folks at THD and they respond to their emails quickly and they actually answer the phones with a living breathing human being. You won't get some ROBOT telling you "press 1 for this---press 2 for that". I called them once and actually talked to Andy Marshall who is the owner of the company! He was the one who answered the phone on the 2nd ring. The best part was we talked for a very long time about tube swapping. He turned me on to some tubes I hadn't thought about using and actually said he would try some combinations I have tried. It doesn't get any better than that in the world of customer service!!!
They're well built and I have had zero problems with them. The JJ's they came with are robust and will give you an idea of what EL 84's sound like but don't expect them to sound like a pair of Amperex Bugle Boys (which I am currently running in mine). Now here is where I am going to start addressing some of the gripes in the reviews below. For the person who said they made a crackling sound until he pushed them in tight but they started doing it again: Deoxidize the tube sockets and the pins on your tubes EVERY TIME you install them!!! The least little oxidation will give you an intermittent signal. I have people bring me amps all the time saying "The tubes were crackling so I put new ones in and they're doing the same thing". HEY PEOPLE---WAKE UP!!! Tube amps need maintenance just like your car. There's a product called Caig Deoxit. They sell it right here at Musician's Friend. If you buy new tubes then buy a can of this too!
For the price point they're a great deal. They're a lot cheaper than buying a Vox AC 30 or some other EL 84 equipped amp. Will they make your Hot Rod Deville sound like an AC 30?--NO!--Will they lower the volume of your amp to where you can play it in the bedroom and not wake the kids?--NO!--For those of you who think a 50 Watt amp is half as loud as a 100 watt amp--Wrong Again!--A 50 watt versus a 100 watt is only 3 decibels less. All you lose with a 50 watter is 3 DB of headroom.
If you want to play in the bedroom and not wake mommy buy an attenuator.

 
3.0

not what I had hoped for

By John

from Austin TX

If you want to change the tone and distortion character of your amp then these *might* be for you. I was mostly hoping to reduce volume on amps that already have great tone but are very loud (I tried them in my Marshall and HiWatt amps). They don't really reduce volume much, a pair of EL84s can still be quite loud. Also they are tall, for example will not fit in my Fender Showman. Using these with the original EL-34 tubes in my 4 tube amp (Marshall) was probably the most interesting thing for me, it added some nice complexity to the tone. But, my local tube amp guru tells me he wouldn't trust them in a valuable vintage amp. Consider the cost and the fact that they essentially are not returnable here... not sure I would buy again.

 
5.0

Nice Tone

By Dill

from Kansas City

I put a pair of these in my Fender Hot Rod Deville 2x12 and it made quite a difference. The OD channel sounds less harsh and a lot more rich. The clean channel gets a slight crunch when I have the volume past 3-4 (didn't before no matter how loud I cranked it), which is exactly what I wanted. My amp doesn't seem like it has quite as much headroom as before, but that's what I was after. Me, along with my band mates all agree that my amp sounds much better now!

 
4.0

I have used it

By Willybooger

from fl

I have used this product.I love the results. pretty much like most have been saying on these reviews. However, you will notice I did not rate too high. Even though it sounds great I think the construction really could use an update, both of mine are very loose and easily turned inside of itself. I feel the wires inside moving around. In pictures you can not see it but it is not a perfect tube cylinder, there are wire bulges around it, feeling a little worried about continued use from all this, so I am looking at Groove Tubes version of this which appears to be better constructed, whether it is or not I will not know until I try them.

(1 of 1 customers found this review helpful)

 
5.0

Smooth and creamy

After spending a couple hundred dollars on various 6L6 tubes trying to get that warm, creamy tone out of my Hot Rod Deluxe that Fender had back in the 50's I decided to try these. Man, I wish Fender would come out with a Hotrod style amp with EL84's instead of 6L6's. These yellow jackets are great and well worth the money to give you that sweet creamy 50's amp tones that Fender was famous for. Great Product!

 
5.0

Jellow Jacket!!

Bought these for my 410 Hot Rod Deville and they do work like advertised. They slightly lowered the output (not a whole lot though), but the most notable thing was the way that it drastically smoothed out the overdrive. I was never real happy with the raspy, overly aggressive overdrive tone that this amp had with the 6L6 tubes. These Yellow Jackets with the EL84s really made a difference with that. They really made a difference with the clean channel too. It truely is like getting a brand new amp. However, after playing for a while I started getting a crackling sound from the speakers. I turned it off and made sure the tubes and the adapters were pushed in all the way and I turned it back on and the crackling was gone. Played for a while longer and the crackling came back. Not real sure what the deal is. Don't know if I should blame it on the YJs or the amp or myself. I'll have to tinker with it some more. Overall, this is a good product. It does just what it says it does. Just be advised that I keep getting a crackling sound from my speakers that I never got with the 6L6s. Think I'll contact THD about it.

 
5.0

A New Amp!

By Big Bob

from So. West Florida

Just put a set of these bad in my 60 watt Fender 410 Hot Rod Deville and WOW! There was a slight decrese in output, not as much a advertised though, but what a difference in tonal quality. The clean channel was clear and crisp, starting to break up when the volume was increased, something that did not occur before. And what a difference when I switch to the overdrive channel ! Pure Heaven ! Smooth and creamy with great definition, no muddy mush here. Using a 335, great sustain that allows the subtle nuances of your playing to be heard. Couldn't be more pleased with the results of this product. I have a new tone monster. If you are considering a mod to your amp, do yourself a favor, throw a set of Yellow Jackets in and hear the difference without hacking up your expensive amp.

 
5.0

Fender Hot Rod or Vox AC

By Bass Player-Tt75X

from Grand Rapids

The only reason I give the features on this less than a 10 is because it didn't do much for lowering the volume on my Fender Hot Rod Deluxe. But I am so please with the tones I'm now getting with my amp. I was never fond of the distorted tones I was getting with the 6L6 tubes, but with the EL84s the distortion is smooth and creamy. And at first I wasn't sure about the clean tone, but the more I play it the more I love it. My amp now has that chime British tone that sound almost exactly like the Vox AC30. So if you're looking for a new amp with a different tonal characteristic try these first. Plus if you need to go back to the 6L6 for the ultra clean low end they provide, its no problem at all, go back and forth as much as you need.

 
5.0

THD Yellow Jackets

By Ivory King

from Chicago

I used these to replace the 6L6 tubes in my 2X12 Hot Rod Deville. Before it was just too loud, and i was never thrilled with any tones that i got out of it using my SG and my 335. If you're expecting to hear a completely different sounding amp, think again. However, I'm really glad i switched the tubes. The amp is still REALLY loud, but overall it's just better! The biggest difference i've noticed is in the clean channel, it just has more character now. I haven't noticed any drop in bass on any channel. I play the amp differently now, with the OD around 3-4 and the volume around 3, and i love the sound!! Definitely worth it, I've got a kick a**rock n roll amp now!

(1 of 1 customers found this review helpful)

 
5.0

Traynor and Yellow Jackets

By Hardtail Dude

from Tampa Bay Florida

I play a Traynor YCV 80 watter with 2 -12 Celestion Vintage 30's. I bought the Traynor because of the clarity of the clean channel, and the need for an all around neutral sound. I knew I was going to experiment with various tubes to get the sound I wanted. I found the overdrive channel to be heavily voiced for the single coil pickups on my Fenders than my Humbuckers on my LP, PRS, and my Dean Hardtail. I installed two Yellow Jackets and experimented with them in various positions and have just fallen in love with the sound of the two at the inner positions, full Class A performance! I did not notice any difference in volume and I play loud here at the house with the master at 5-6. This is all that is needed to get this amp cooking with only two tubes. I can actually get better controlled breakup with the EL84's than my Groove Tubes 6L6's with much more tone available. The Traynor already had a real tight creamy sounding gain but this now goes into more of a Jimmy Page, Queen sound especially with the neck pick-up... sort of a Vox on demand depending on how hard you drive the tubes. My Dean Hardtail sounds like Billy Gibbons and nails ZZ Top on the nose! I got pinch harmonics on my PRS, and my American Tele with the Samerian Cobalt single coils is now totally alive I can actually here the difference when I hit the coil tap! Just for kicks I plugged in my MIM Fender Nashville and wooooh I got Stevie Ray breathing fire out of this once cold, sterile sounding Traynor amp. I am buying another set to complete this unit back to 4 output tubes then I am starting on a set for my Fender Hot Rod Deville. I can't say enough good about these little rascals they are just the most electronics bang for the buck. In the Traynor which had more of a Mesa Boogie sound than a Marshall it doesn't sound like a Vox at least not the Voxes I have heard so I don't know what it will sound like in other amps. I tried it in my Fender Hot Rod Deville and this did sound like a Vox but I have a cracked speaker so I can't make a good review on that one. Hey its a new amp with a sound you might like if nothing else you can swap tubes and get the Vox sound when you want it.

Displaying reviews 1-10

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