6CA7 power tubes in your Archon 100?

boardn10

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Has anyone tried 6CA7 tubes in the Archon 100?
I have 6L6s now but I did try E34Ls and 6CA7s, and settled back on 6L6s.
I didn't notice large differences, only very minor differences.
I know many modern amps are mostly preamp and circuit driven, while power tubes make minor adjustments.
PRS makes the current import Archon 50 with 6CA7 tubes. I love those tubes in my Mesa Boogies, but I think I prefer 6L6 power tubes in my Archon 100.

Curious your thoughts.

Thanks!
 
Has anyone tried 6CA7 tubes in the Archon 100?
I have 6L6s now but I did try E34Ls and 6CA7s, and settled back on 6L6s.
I didn't notice large differences, only very minor differences.
I know many modern amps are mostly preamp and circuit driven, while power tubes make minor adjustments.
PRS makes the current import Archon 50 with 6CA7 tubes. I love those tubes in my Mesa Boogies, but I think I prefer 6L6 power tubes in my Archon 100.

Curious your thoughts.

Thanks!
The characteristics of the power tube become more apparent as the master is cranked up and the channel gains lowered. In the amps I have where the EL34s don’t get juiced up a bit, they sound less full than 6L6s. The 6L6GC is one of the great all-around tubes, and never seems to sound bad, even in amps where it doesn’t sound “best.” The EL34 (and likely the 6CA7, though I don’t have much experience with it) really comes into its own when the power stage is pumping. That’s when it makes the sound it’s famous for, in my opinion.

In the end, though, assumptions can be tossed in the trash. What sounds best to you is best. I’ve also got 6V6 and EL84 amps that sound great, so it’s a lot more than just tubes factoring into the sound. If it’s sounding good, forget the gear and enjoy the inspiring tone.
 
Thanka for the info and feedback.

Do you find brand of power tubes makes a big difference? So the Archon has Ruby 6L6 and I am trying JJ 6L6..
I think they are so similar that brand is minor.
My Mark V had Sovtek.
 
Thanka for the info and feedback.

Do you find brand of power tubes makes a big difference? So the Archon has Ruby 6L6 and I am trying JJ 6L6..
I think they are so similar that brand is minor.
My Mark V had Sovtek.
Again, it depends on the volume you’re playing at, which kind of dictates whether your drive is coming more from your channel gains (preamp) or master (power amp). The really good sounding NOS tubes like the RCA black plates or SED/Winged C are on the expensive side these days and, frankly, if you’re not pushing the masters the return on that investment might be less than what you expect… although I have to say I like the mental confidence of having the tubes I like even when I’m not setting the amp where they shine most. That’s just me!

In my personal experience, PRS does a great job on selecting tubes for their amplifiers. You could do a lot worse than using what they put in it originally! But if you’d like to try something new, there’s no harm in giving it a shot. You won’t hurt the amp!
 
Great points.
I have the stock Ruby 6L6s, some JJ 6L6s and So tek 6L6s.
At rehearsal I have thr master at about 10:-10:30.
Love the 6CA7s but it seemed dark at rehearsal in my Mark V.
I have been running JJ 6l6 tubes in my Archon but I may go back to the stock Ruby 6l6 tubes.

One 6ca7 blew in my Dual Rec C and I want to move the 6ca7 s from my MkV to thr Dual Rec and the JJ 6l6s from the Archon to the MkV. Then the Archon would go back to stock Ruby tubes. But, before doing that, I want to test the 6ca7s in the Archon. I just don't know how loud I can get it at home.

My Mark V loves 6ca7 tubes but they seem dark at band practice. I'm wondering if the PRS will be as dark wirh them.

The true test for any of this, is when I use the amp at practice. At home, I can't get the PRS Master over 9:00.
 
The characteristics of the power tube become more apparent as the master is cranked up and the channel gains lowered.
THANK YOU for saying this, Rick! I see so many guys rolling power tubes in amps that are driven and voiced by pre-amp gain, and being used in situations where they can’t be played above 3 on the volume knob. I just wonder if it’s worth the trouble...
 
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The true test for any of this, is when I use the amp at practice. At home, I can't get the PRS Master over 9:00.
Trust your ears. If you can’t hear a difference, then to you there is no difference, no matter what friends or “experts” say! With the settings you describe, a good brand with a reliable, well-made power tube will be a good move. The differences you may detect will be subtle. The tone while playing with the band is what you want to look for, as it’s the best test of the tone your audience will be hearing.

Sometimes, and I’ve been guilty of it, guitarists more like the idea that a sexy, special tube will give them the “unattainable tone of legend” than they like anything the tube actually does. This can lead to spending lots of money on very little gain; sometimes customizing ourselves right out of a good tone. Go with your ears. :)

You might also try preamp tubes… it’s much cheaper than power tubes, and will likely have a more apparent effect on your sound, at the settings you mentioned. Just start with your V1 preamp tube, as it generally has the greatest impact.

Consider setting the amp back to stock between tests so that you can get an effective A/B idea of what changes. Another often overlooked component, but more impactful than most tube swaps, are speakers/cabs. Try plugging your amp into your friend’s cab. It can be a real eye-opener. Happy testing!

THANK YOU for saying this, Rick! I see so many guys rolling power tubes in amps that are driven and voiced by pre-amp gain, and bing used in situations where they can’t be played above 3 on the volume knob. I just wonder if it’s worth the trouble...
Oh yeah, I learned that lesson the hard way… the search for the glowing Holy Grail. It’s frustrating to get to that place where you have to admit “I spent a lot of money on this and, damn, I just don’t like the way it sounds!” or “It sounds exactly the same as it did back when that $200 was still in my checking account.” It’s a search, and you don’t know until you know… I get that. But I wasted less money once I got a better understanding of what does what, so I try to share that when the opportunity presents itself. :D
 
So true...
Some amps respond more than others, but for the most part, it's a tiny difference.
I don't hear or feel any difference between the brands of power tubes in my amps. Tiny at best.
 
So true...
Some amps respond more than others, but for the most part, it's a tiny difference.
I don't hear or feel any difference between the brands of power tubes in my amps. Tiny at best.
Yep, that’s been my experience with many amps. Some, like my HXDA, benefit from different power tubes because I run the master at about 65-75% most of the time, and occasionally dime it. That circuit just loves power amp grind. Some of my other amps are too powerful for that (like your Archon, I suspect), so good preamp tubes and a speaker I like gets me to a great sound. It’s fun to chase the magic component, but keeping expectations realistic saves me a lot of money. In truth, my amps all sound just fine 100% as purchased. After all, that’s why I bought them!
 
Great points again.
I spent too much on power tubes for my Mark V, 6L6 and 6CA7, but the different brands of 6L6 was wasted money.
I do notice the difference with type of tubes, only at band rehearsals.
Essentially, I have backup tubes now.

In the Archon, I may just leave the Ruby 6L6.
Intereating that in the new literature for the Archon, PRS mentions that they use 6CA7 tubes for the balance between EL34 and 6L6. You provide bbaly won't ever notice that unless you turn the master up a lot.

Now, my Bogner Shiva, I ran the master sometimes halfway up.

I even bought all new preamp tubes for my Mesa Boogies and again, the difference was tiny.
 
The thing I hate is that I can never try an amp before buying. Stores don't carry many amps these days so I never know if I will like the amp, until I actually buy and receive it.
So I rarely play an amp because I like it, but more because I think I will like it.
 
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The thing I hate is that I can never try an amp before buying. Stores don't carry many amps these days so I never know if I will like the amp, until I actually buy and receive it.
So I ararelybiy an amp because I like it, but more because I think I will like it.
Yes, a problem of the internet age! I try to do business where I have a 10-30 day return policy for that reason. But you can’t always get that, especially with used gear. There used to be 3 or 4 music stores in my immediate area, now just 1, and it doesn’t carry what I’d call pro-level gear. So it’s a 120 mile round trip to the nearest Guitar Center, for instance. Thankfully, my gear needs are near-zero with gigging at a standstill. I have more amps and guitars at this moment than I’ll ever need, and that by a healthy margin! I’m in a good place.
 
I do my best to listen and read reviews and go off what I know from 36 years of playing and then take a chance on used. I was blown rn in 1970 and I see you were born in 1960.
I can always flip it.
I like the Archon a lot and better than my Shiva I had prior. It still can do the British crunch with the right EQ and pedals, etc.

We used to have a lot of music stores. We still have some good shops but they don't carry pro level gear. I am outside Philly and there is a shop in jersey that carries high end gear, but no PRS.

We have been gigging for a while again.
No gigging in your area?
 
Oh yeah, I learned that lesson the hard way… the search for the glowing Holy Grail. It’s frustrating to get to that place where you have to admit “I spent a lot of money on this and, damn, I just don’t like the way it sounds!” or “It sounds exactly the same as it did back when that $200 was still in my checking account.” It’s a search, and you don’t know until you know… I get that. But I wasted less money once I got a better understanding of what does what, so I try to share that when the opportunity presents itself.

Agree. And, when I was building SE amps with one preamp tube, one power tube and two knobs, and cranking them up, it was the norm that you could easily hear the differences in tubes. Sometimes, they were big, sometimes they were not but you could hear them pretty easily.

But those were VERY simple circuits and were low enough power that you could crank them up. (Side note: OT's were VERY easy to identify as well, moreso than many tubes!) The more gain stages, and circuitry you add, the less identifiable each individual aspect or change becomes. And I'm not saying that changing V1 on an amp with 5 pre-amp tubes can't be heard. It usually can. Just that in the grand scheme of things, each component is less readily identifiable. I believe amps become less and less transparent with each added component, and in amps with more pre-amp gain, the power tubes are not as important.

Simple test: Something like a JCM800 doesn't really have that much pre-amp gain. Put a good, well chosen NOS tube in the PI slot, or even the preferred new one, the Sov Tech 12ax7 lps. Push the amp hard, and you WILL hear the difference in pretty much every PI tube swap you make. In that circuit, when pushed, the PI is a BIG part of the sound! In fact, that is what most people incorrectly identify as "power stage distortion." That power stage can hit 140 watts or more before it compresses some, not distorts, in most JCM 800s. It's PI stage overdriving that most people think is power stage distortion. Swapping that PI tube makes a significant difference in that amp!

Now, try it in a Mark V or Archon with the master at 3. You might hear a difference in swapping PI tubes, and unless one tube is bad, it probably won't be worth the trouble. The gain is in the preamp stages and you aren't pushing the PI hard enough to matter. Turn the gain WAY down, push the power amp way harder, and then maybe it will become a bigger difference. Probably still less so though, since so much of the voicing comes from the pre stages.
 
Good stuff guys! Thanks.

In my current amps, I tried the Sovtek in the PI, and couldn't hear a difference.
Its all so minor now when it comes to tube swaps, due to the circuits.
 
Good stuff guys! Thanks.

In my current amps, I tried the Sovtek in the PI, and couldn't hear a difference.
Its all so minor now when it comes to tube swaps, due to the circuits.
The LPS? That's the one that sounds so good in the PI position IF you have an amp design that pushes the PI and depends on that stage for a significant amount of the OD.
 
The LPS? That's the one that sounds so good in the PI position IF you have an amp design that pushes the PI and depends on that stage for a significant amount of the OD.
Exactly. I don't notice it in my amps, like the Archon - but I know I would in some of the amps I used to own.
 
Running the stock JJ and Ruby tubes in my Archon with all knobs at about noon, sounds glorious, with master at 9:00.
I always was told that 6L6 tubes are scooped and glassy, and PRS switched to 6CA7, but man my Archon sounds smooth and thick, even for leads with the 6L6 tubes. I thought it sounded less clear with the 6CA7 tubes. Sounds perfect as is.
I surprised PRS switched to 6CA7.
 
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Running the stock JJ and aruby tubes in my Archon with all knobs at about noon, sounds glorious, with master at 9:00.
I always was told that 6L6 tubes are scooped and glassy, and PRS switched to 6CA7, but man my Archon sounds smooth and thick, even for leads. :)
There ya go. Your opinion is the only one that counts on that!
 
THANK YOU for saying this, Rick! I see so many guys rolling power tubes in amps that are driven and voiced by pre-amp gain, and being used in situations where they can’t be played above 3 on the volume knob. I just wonder if it’s worth the trouble...

I would say it depends on the amp, the tube, the player, the playing style, and - often overlooked - the room the amp is sitting in, since when you hear an amp in a room, you're hearing the speaker plus all the reflections off the walls, floor and ceiling. The room itself can augment or interfere with the sound reaching your ears, or it can be neutral, but it shouldn't be discounted as one among other variables.

You probably read my post about the Telefunken 6L6s making a difference in my 100 Watt Lone Star. Heck, you may have posted in that thread?

In any case, the Lone Star is an amp with 5 preamp tubes, and those 5 preamp tubes create much of the amp's tone. Granted, I have NOS GE, RCA and Siemens 12AX7s in the amp, stuff that I think helps make the details in the tone more clear, but the 6L6 tube swap was indeed transformative. It's difficult to describe tone with words, but I felt the overall tone became more lush, with very clear high end, but less harshness at the topmost frequencies.

Of course, I don't know how or why this voodoo worked. All I know is that it worked.

While I also play at higher master volume settings often, this improvement was apparent at very low volume levels. It sounds consistently improved at a variety of levels, actually.

So you just never know. If there's no tone difference in one amp following a tube swap, there still might be a difference in another amp, or with a different playing style, or one of thousands of other variables I can't even think of.

I should mention that I have quite a bit of high quality acoustic treatment in my room, so that might help me hear certain details. I will also remind the reader that I am a complete lunatic when it comes to audio, so there's that. ;)
 
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