I have a SE84UFO2 on order, and it seems it is pretty forgiving about using different tubes. Taking what I see from Decware directly, for the three applications I see:
OUTPUT:
6P15P-EV
SV83
EL84
6BQ5
INPUT:
6N1P
6922
6DJ8
7DJ8
6N5P
6N23P
RECTIFIER:
5U4G
5U4
5AR4
5Y3GT
274B (not all compatible)
What I am trying to understand is the differences, which have multiple models but are otherwise the same tube, or anything else to be aware of.
I did see this sticky, started in 2004 and a TON there. Not being lazy, just wondering if there is one good resource to start with
https://www.diyaudio.com/forums/tubes-valves/38278-line-tube-learning-newbies.html
Thanks!!!
OUTPUT:
6P15P-EV
SV83
EL84
6BQ5
INPUT:
6N1P
6922
6DJ8
7DJ8
6N5P
6N23P
RECTIFIER:
5U4G
5U4
5AR4
5Y3GT
274B (not all compatible)
What I am trying to understand is the differences, which have multiple models but are otherwise the same tube, or anything else to be aware of.
I did see this sticky, started in 2004 and a TON there. Not being lazy, just wondering if there is one good resource to start with
https://www.diyaudio.com/forums/tubes-valves/38278-line-tube-learning-newbies.html
Thanks!!!
Your SE84UFO2 wont be "forgiving" if you think you can plug in a =5Y3GT tube into a socket designed for a 5U4 /G---there is the "small " difference of a cathode involved but you will enjoy the "Halloween " shower of internal sparks .
I will let others run down the list for you , what I don,t understand is why you don't either read a book on tubes for beginners or spend some time reading up online ?
I will let others run down the list for you , what I don,t understand is why you don't either read a book on tubes for beginners or spend some time reading up online ?
From their site (written by Steve). I didn't think there was a lot of interpretation when this is literally written by the guy who built your amp? What am I missing?
"The rectifier location is compatible with 5U4G, 5AR4, 5Y3GT, and some 274B. Many owners of this amp like using the 274B however not all 274B tubes are completely compatible, so we ship the amp with one that we know IS. Each rectifier change will also make audible differences in the sound and performance of the amplifier."
And I am also literally doing what you suggest...reading up online (rather, asking for those who know more than me to suggest something that they know to be true vs. me just finding random things written by people who might not know what they are talking about).
I've posted a few times there, but it seems to not get a lot of traffic. Otherwise I would be all over that.
From the Decware website regarding the SE84UFO:
This amp is shipped with hand-selected premium quality 6P15P-EV output tubes rated at 5000 hours. These tubes have been branded "SV83" in past years.
NOTE: You can also use EL84/6BQ5's in this amplifier without adjustments of any kind. If you compare the these to the supplied 6P15P-EV’s you may find the included later to be unparalleled in speed and detail. The reason for this is because the 6P15P-EV is actually a video tube with much wider bandwidth than many audio tubes, and this gives a sense of great speed when listening to music on a Zen Triode amplifier.
We think these small output tubes are some of the best sounding and best-quality available today. Of course, with all the EL84/6BQ5 options out there, you can have a lot of fun experimenting without breaking the bank!
The input tube shipping with the amp is a 6N1P-EV. The amp is, however, also compatible with 6922 or 6DJ8 or 7DJ8. 6N1Ps have the warmest tone, 6922s have the best dynamics. 6DJ8s have the most air and micro-detail with a touch less bass. Again, a few different tubes can be a powerful tool for voicing your amplifier to your particular tastes.
The amplifier ships with a 5U4 rectifier tube. In place of the 5U4, you can use a 5AR4, 5Y3GT, and certain types of 274B .
Since there's also a lifetime warranty and the company website lists the tubes you can use, I don't know of any other information here that can be provided?
I had one of these amps. They are great sounding amplifiers. Well made and with a lifetime warranty. I'm 62 years-old and have a shorter life expectancy than someone in their 20s, obviously.
My Decware SE82 was sold because it was my only amplifier at the time and didn't get loud enough on those occasions when I wanted to blast the music. If you like your music loud, I would suggest a tube amp that has at least 8 watts or more, and that your speakers are >90% efficient.
This amp is shipped with hand-selected premium quality 6P15P-EV output tubes rated at 5000 hours. These tubes have been branded "SV83" in past years.
NOTE: You can also use EL84/6BQ5's in this amplifier without adjustments of any kind. If you compare the these to the supplied 6P15P-EV’s you may find the included later to be unparalleled in speed and detail. The reason for this is because the 6P15P-EV is actually a video tube with much wider bandwidth than many audio tubes, and this gives a sense of great speed when listening to music on a Zen Triode amplifier.
We think these small output tubes are some of the best sounding and best-quality available today. Of course, with all the EL84/6BQ5 options out there, you can have a lot of fun experimenting without breaking the bank!
The input tube shipping with the amp is a 6N1P-EV. The amp is, however, also compatible with 6922 or 6DJ8 or 7DJ8. 6N1Ps have the warmest tone, 6922s have the best dynamics. 6DJ8s have the most air and micro-detail with a touch less bass. Again, a few different tubes can be a powerful tool for voicing your amplifier to your particular tastes.
The amplifier ships with a 5U4 rectifier tube. In place of the 5U4, you can use a 5AR4, 5Y3GT, and certain types of 274B .
Since there's also a lifetime warranty and the company website lists the tubes you can use, I don't know of any other information here that can be provided?
I had one of these amps. They are great sounding amplifiers. Well made and with a lifetime warranty. I'm 62 years-old and have a shorter life expectancy than someone in their 20s, obviously.
My Decware SE82 was sold because it was my only amplifier at the time and didn't get loud enough on those occasions when I wanted to blast the music. If you like your music loud, I would suggest a tube amp that has at least 8 watts or more, and that your speakers are >90% efficient.
Thanks. I read that and am trying to understand a little better technically *why* I can use some seemingly incompatible tubes. For example, found this comparison chart:
The amp ships with a 5U4, but I can use other tubes that don't meet that spec (some that have lower output?). Is it because am amp is not needing the full potential of the tubes so a lower-power tube can survive because it is never being pushed over the limit?
Specifically, I have some tested NOS RCA 5Y3GT's that I'd like to use, but looking at this chart would suggest they don't have as much output (that is probably not the right term).
The amp ships with a 5U4, but I can use other tubes that don't meet that spec (some that have lower output?). Is it because am amp is not needing the full potential of the tubes so a lower-power tube can survive because it is never being pushed over the limit?
Specifically, I have some tested NOS RCA 5Y3GT's that I'd like to use, but looking at this chart would suggest they don't have as much output (that is probably not the right term).
Original owner. I'm in my 30's, so I'm feeling lucky. No, tubes not included!
canonken- these rectifier tubes work with the power transformer amperage ratings and the other criteria shown. You'll find that the power transformer will run hotter or cooler depending on the rectifier tube you use. That's only one reason.
Some people will claim they can hear a difference between rectifier tubes. That's good for them. I can't hear a difference, and I've got all the rectifier tubes shown in your chart. I do know that some hobbyists prefer the 5AR4 tubes because they have a slower start up and don't hit your output tubes with a big surge of current and voltage as soon as you flip the switch on. This is all good for tube life, especially if you are going to use your amplifier on a rocket ship to Mars or on a fighter plane, or other equipment that needs to have high reliability.
Tubes are also radiation hardened, but if you're close enough to a nuclear detonation, you're going to be fried regardless of if you have vacuum tube gear or not.
Tube gear is fun because you can do some tube rolling. Just be aware that the tubes you change out which make the most difference in the sound of the amp with his amp will be the driver tubes. Those are the 6V15P, 6DJ8, 6922, etc. Be aware that these tubes are not cheap. Neither are the output tubes or Mullard 5AR4 tubes. In my opinion, the expensive tubes don't make that big of a difference to justify the cost.
But, you might think a $90k Tesla is worth the cost of the limited driving range and having to plan your trip around the availability of charging stations.
Some people will claim they can hear a difference between rectifier tubes. That's good for them. I can't hear a difference, and I've got all the rectifier tubes shown in your chart. I do know that some hobbyists prefer the 5AR4 tubes because they have a slower start up and don't hit your output tubes with a big surge of current and voltage as soon as you flip the switch on. This is all good for tube life, especially if you are going to use your amplifier on a rocket ship to Mars or on a fighter plane, or other equipment that needs to have high reliability.
Tubes are also radiation hardened, but if you're close enough to a nuclear detonation, you're going to be fried regardless of if you have vacuum tube gear or not.
Tube gear is fun because you can do some tube rolling. Just be aware that the tubes you change out which make the most difference in the sound of the amp with his amp will be the driver tubes. Those are the 6V15P, 6DJ8, 6922, etc. Be aware that these tubes are not cheap. Neither are the output tubes or Mullard 5AR4 tubes. In my opinion, the expensive tubes don't make that big of a difference to justify the cost.
But, you might think a $90k Tesla is worth the cost of the limited driving range and having to plan your trip around the availability of charging stations.
It's the owner , not the component itself then that has warranty.
That does not feel good.
Thanks. I know the sound quality is a whole other topic (for debate), I just want to understand the differences, but ultimately the compatibility as to not hurt the amp or the other tubes. Based on what I see online about this amp, it seems forgiving/flexible and easy on tubes (which intuitively makes sense if everything is being under-utilized and is under low stress, low heat).
I see on other amps like the MC275 the 7 'small' tubes are often said to last in excess of 10,000 hours because the amp is designed well and they are not being stressed much - and even the power tubes can last a very, very long time because of good amp design and them not being driven too hard.
In this day and age, the last thing I would want would be an amp that is trying to push the limits of a tube for a little more output.
(I am down river from at least one nuclear power plant!)
I see on other amps like the MC275 the 7 'small' tubes are often said to last in excess of 10,000 hours because the amp is designed well and they are not being stressed much - and even the power tubes can last a very, very long time because of good amp design and them not being driven too hard.
In this day and age, the last thing I would want would be an amp that is trying to push the limits of a tube for a little more output.
(I am down river from at least one nuclear power plant!)
I don't see the problem. I plan on keeping this thing for a long time (it's fallback position will be driving my computer speakers, which love a good, low-power amp) or driving some of the other things I have. In a sense this warranty is a sarcastic way of saying 'this thing is not going to break, so if it dies before you do, I'll make it good'.
Other than Bryston (20 years on amps, not everything) and a few others, 1, 2, 3 years is the norm.
What that graph doesn't show is the base designations of the tube pin layout , I know the amplifier ships with a 5U4 therefore its hard wired to the rectifier base in that tubes pin layout .
it has -
pin 2= heater.
pin 4= plate.
pin6=plate.
pin8=heater
Notice NO cathode .
5Y3G-
pin 2=heater.
pin 4=plate.
pin 6=plate.
pin 8=cathode/heater .
Notice the tube base incompatibility ?
Unless your amp was getting sold as a kit and you had to wire it up it is irresponsible of the seller to give the impression that the 5U4 base /5V4 can be directly substituted by just being plugged it into the 5U4 base .
it has -
pin 2= heater.
pin 4= plate.
pin6=plate.
pin8=heater
Notice NO cathode .
5Y3G-
pin 2=heater.
pin 4=plate.
pin 6=plate.
pin 8=cathode/heater .
Notice the tube base incompatibility ?
Unless your amp was getting sold as a kit and you had to wire it up it is irresponsible of the seller to give the impression that the 5U4 base /5V4 can be directly substituted by just being plugged it into the 5U4 base .
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Decware offers a transferable warranty if the amp is sent back to their factory and checked out by them. Of course, there is a fee.
My experience with older gear is that there are components which go obsolete and the original manufacturer does not have any replacement parts.
I was able to buy a replacement faceplate for my McIntosh MC2205. Pretty good for an amp that was made in 1975. Decware has been around since about 1998, so I would say for me, the lifetime warranty is good for at least another 20 years.
canonken- my advice would be to buy the Decware SE84XXX, especially if you're new to tube amps and have some efficient speakers. All the tubes used on the amp are available. Some are more costly, but the tubes provided when you buy the amp will last for many years.
Have fun, enjoy the music.
My experience with older gear is that there are components which go obsolete and the original manufacturer does not have any replacement parts.
I was able to buy a replacement faceplate for my McIntosh MC2205. Pretty good for an amp that was made in 1975. Decware has been around since about 1998, so I would say for me, the lifetime warranty is good for at least another 20 years.
canonken- my advice would be to buy the Decware SE84XXX, especially if you're new to tube amps and have some efficient speakers. All the tubes used on the amp are available. Some are more costly, but the tubes provided when you buy the amp will last for many years.
Have fun, enjoy the music.
Warranty is just a contract between buyer and manufacturer and it essentially means, in practical words, that IF manufacturer does not honor the Warranty, you can sue him.
Or attack him used that "dreaded weapon" called "I´ll smear/burn you on Internet"
Good luck using any of them after *Manufacturer* dies, or even goes Chapter 11 bankrupt or equivalent.
Or moves out of the Country or ... or ... or ...
In practice, it holds water while Manufacturer is active, which is an unknown number of years.
In the UK under the "Sale of Goods Act " if buying from a high street shop , regardless of the warranty if goods are defective then its the shops responsibility not the manufacturer in the first place to replace or return the money laid out for the purchase of the goods .
Trying to get your money back online is now a "joke " even Amazon has "disowned " its "Marketplace " due to the large number of scams taking place .
Its legally divested its responsibility under US law quite recently and applies it to foreign countries even if they don't come under US legal jurisdiction .
Every day I still receive emails from the website I helped people on in the UK complaining about being either scammed or ignored when asking for money back for faulty goods when buying online.
Trying to get your money back online is now a "joke " even Amazon has "disowned " its "Marketplace " due to the large number of scams taking place .
Its legally divested its responsibility under US law quite recently and applies it to foreign countries even if they don't come under US legal jurisdiction .
Every day I still receive emails from the website I helped people on in the UK complaining about being either scammed or ignored when asking for money back for faulty goods when buying online.
True, these tubes are NOT directly compatible in ALL possible applications. It is however possible to design an amplifier that could use any of these tubes for ONE specific application. In this case it is apparently a Single Ended stereo amp that uses one EL84 type tube in each channel.
It is exactly that. In this case the EL84's need about 40 to 50 mA each, and the 6DJ8 needs maybe 10 mA, for a total of about 110 mA. Any rectifier tube that has a compatible pin configuration and can supply 110 mA or more, meets the AC voltage and input capacitor requirements should work. Each will give a different B+ voltage, and have a different internal voltage loss, so they will all sound different.
The 5Y3 can not pass as much current as the 5U4, but your amp doesn't need it, so it's OK. It does drop (lose) more voltage in use, so your power supply (B+) voltage will be a bit less. This can impart a different sound quality and a slightly lower maximum power output. The difference depends a lot on your music choice, speakers, and how loud you play it. The difference between a 5Y3 and a 5U4 may be slight, or huge. There is only one way to find out. The 5AR4 has the lowest loss, and therefore produces the most power supply voltage output, primarily because it does have a cathode. It is also the most popular rectifier choice in my SSE amp.
I have been selling the PC board (the SSE) for a similar, but higher powered SE amplifier for 15 years. It uses either a 6L6GC, EL34, 6550, or KT88 for the output tube. These are NOT compatible with each other in all designs. The rectifier can be a 5AR4, a 5U4, in some cases 5R4's and 274B's can be used. It can NOT use a 5Y3 in most builds because the larger output tubes can draw 70 to 100 mA each for a total of 175 to 225 mA. There is an option to make a lower powered amp with 6V6GT output tubes, in which case a 5Y3 can be used. This uses a smaller transformer set do avoid frying these lower powered tubes.
A true 5Y3 does not have a cathode. It is directly heated just like the 5U4. The 5AR4 DOES have a cathode, but it is internally connected to the heater at pin 8, therefore electrically pin compatible with the 5U4 and 5Y3 in this respect. There are many differences between all of the rectifiers mentioned in this thread, the biggest is filament / heater current. The 5U4 draws 3 amps and can not blindly be substituted for ANY of the 2 amp heater tubes. The DC current ratings, voltage drop, maximum input capacitor value, and AC plate voltage specs are also different, so in general NONE of these tubes are directly compatible with each other.
I state a pretty long list of tubes that I personally have tried and approve of in my amplifier designs, and under which other conditions they can or can not be used. I assume that the designer of this amp has also done the same, but I have never actually seen a Decware amp.
It is exactly that. In this case the EL84's need about 40 to 50 mA each, and the 6DJ8 needs maybe 10 mA, for a total of about 110 mA. Any rectifier tube that has a compatible pin configuration and can supply 110 mA or more, meets the AC voltage and input capacitor requirements should work. Each will give a different B+ voltage, and have a different internal voltage loss, so they will all sound different.
The 5Y3 can not pass as much current as the 5U4, but your amp doesn't need it, so it's OK. It does drop (lose) more voltage in use, so your power supply (B+) voltage will be a bit less. This can impart a different sound quality and a slightly lower maximum power output. The difference depends a lot on your music choice, speakers, and how loud you play it. The difference between a 5Y3 and a 5U4 may be slight, or huge. There is only one way to find out. The 5AR4 has the lowest loss, and therefore produces the most power supply voltage output, primarily because it does have a cathode. It is also the most popular rectifier choice in my SSE amp.
I have been selling the PC board (the SSE) for a similar, but higher powered SE amplifier for 15 years. It uses either a 6L6GC, EL34, 6550, or KT88 for the output tube. These are NOT compatible with each other in all designs. The rectifier can be a 5AR4, a 5U4, in some cases 5R4's and 274B's can be used. It can NOT use a 5Y3 in most builds because the larger output tubes can draw 70 to 100 mA each for a total of 175 to 225 mA. There is an option to make a lower powered amp with 6V6GT output tubes, in which case a 5Y3 can be used. This uses a smaller transformer set do avoid frying these lower powered tubes.
A true 5Y3 does not have a cathode. It is directly heated just like the 5U4. The 5AR4 DOES have a cathode, but it is internally connected to the heater at pin 8, therefore electrically pin compatible with the 5U4 and 5Y3 in this respect. There are many differences between all of the rectifiers mentioned in this thread, the biggest is filament / heater current. The 5U4 draws 3 amps and can not blindly be substituted for ANY of the 2 amp heater tubes. The DC current ratings, voltage drop, maximum input capacitor value, and AC plate voltage specs are also different, so in general NONE of these tubes are directly compatible with each other.
I state a pretty long list of tubes that I personally have tried and approve of in my amplifier designs, and under which other conditions they can or can not be used. I assume that the designer of this amp has also done the same, but I have never actually seen a Decware amp.
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