Eddie only used these because he got them cheap from the tv repair guy. He also used the variac as a volume control, the tone he got using it was a happy side effect!
The 6ca7 sound a bit warmer with a little less upper mid / low treble emphasis which I think is a good thing. Rolling a few NOS tubes through the preamp/PI might yield some good results but NOS can get a little expensive these days. I’m really enjoying following your journey in this restoration project. Thanks for sharing it with us all Jason.
I've rolled NOS PI tubes through several amps, and have have ended up liking new production JJ Ecc 803 there, ironically. They have sweet highs, and tighten the bass. A NOS Telefunnken short plate yields similar result but with peaked highs IMO.
I put a set of the same Sylvanias in my Origin 20C. I noticed the e.q. behaved completely differently and that I was happier. I tried some German Amperex EL-34's but preferred the big bottle Sylvanias. I have a Celestion Greenback to try next. Then I'll be all out of easy plug and play mods and I'll have to do your Plexi mod or just get an SV-20.😂😂😂
The difference is very very subtle. I preferred the EL34s in this comparison, they seem to have more oomph thanks to their stronger upper mids... they sound “more Marshall” 😃. We can see how Eddie chose the 6CA7s to tame that and have a “browner” result, but I don’t believe the change is worth the game, especially nowadays (even before the Russian supply problem).
Here in los angeles all thru late 70's and 80 's i would take my 68 50 marshall plxi to valley arts. For retube and bias every 6 months . one time he put 6ca7 tubes instead of the telefunken el 34 tubes . i took it right back and told him it sounded fu#%ed up so anyway he put in the el34 and apologised my amp sounded like a bandmaster or something i hated it but here it sounds close he bias'ed it to cold ? With 6ca7 i dont no . my 2 cents on this great show love that plxi grind cheers
Very nice comparison. I was wondering about the 6ca7’s. Listening to the guitar alone I prefer the 6ca7’s. Don’t know in a mix which ones will I prefer. The bottom end seems very similar. I think that the midrange is thicker or on the lower mid side on the 6ca7’s and on the higher mid on the el34’s. The top end is sweeter on the 6ca7’s, more extended or brighter on the el34’s. Both sound very good. I guess some people will prefer the brightness of the el34’s some will prefer the bolder sound of the 6ca7’s. On this test I prefer the 6ca7’s
Love the 6CA7 tubes! I have them in my Plexi too. Really awesome tube! Has a bite and bark to them which I prefer to the EL84s. Coupled with a couple of Mullard and GE preamp tubes it’s tone heaven! Great tones as always Jason. Have an awesome day dude!
Awesome Jase! I thought the 6ca7’s sounded a whisker warmer and less harsh if you like ... not to say the mullards were harsh though, they still sounded great! Great vid mate.
Well, I'm going to be the contrarian here and say that I didn't hear enough of a difference that it mattered.... but if YOU did and YOU are happy, that is all that matters. :) I actually tried this in my '76 JMP 2203 and didn't hear much of a difference either, certainly nothing that a slight twist of the knobs didn't balance out. I'm running KT77s here... they just seem to run best in my amp which has a really hot PT. In any case your amp sounds killer!
I changed out the EL-34’s for 6Ca7’s in my 87 Jubilee years ago…I like the 6Ca7’s much better….they are a little fuller,but have something special going on in the mids…They still have that 34 cut,but the highs are a little sweeter…..I think on the clips,they sound great in your Marshall…I just ordered a new set of JJ 6Ca7’s..haven’t gotten them yet,but hopefully they will sound close to the NOS ones….I think I read that EVH used them because they can take a little higher plate voltage,he was hoping they would last longer than EL-34’s….
Both sets of valves sounded great. The amp is just awesome. So I reckon preference is a matter of personal taste. I preferred the Mullards. More high midrange bite. Slightly less low end though. So, I guess when playing on your own, the USA valves sound fuller. But in a mix, the Mullards should cut through slightly better.
The 6CA7s seem a little more “natural” on the clips. More solid in the lows, a smoother midrange that has some clarity to it. Those 34s had an almost fuzzy upper mid character to them by comparison. I can understand why some may like that (because it gives the appearance of having more distortion), but it’s not the most natural or clear sound by any stretch.
That's referred to as "swirl". It's a side effect guitarists tend to like of EL34 pentodes not having aligned grids. The electrons bounce around and create a wilder high-end. It can actually cause catastrophic failures from runaway bias depending on the amp design. EL34's may actually break up earlier than the 6CA7 as well. I'm not sure, but pentodes do generate stronger 3rd harmonics than power (Beam) tetrodes. That's another reason they sound clearer. They also sound more dynamic to me, and I don't think they compress near as much.
The 6CA7 certainly removed some of the fluff from the EL34. Have you ever tried E34L in comparison to EL34? Ive had them in a Stiletto in the past and thought they were a great readily available option to the standard EL34
@@HeadfirstAmps Congratulations, it's a keeper for sure. I have one of these and it's definitely one of my best amps. I was surprised that the reissue Mullards sounded as good as they did.
I can move my head and make a bigger difference in tone than there is between the two. This is cork sniffing at its finest. There's a les Paul group I'm on, where they claim that brass caps on the back of the pots are warmer sounding.
Both sound good to me , I do prefer the Fatboys.if your chasing EVH Tone, Try a Sylvania 12ax7 in the first Preamp if you have a spare one lying around.
You should make it clear in the video that Mullards is a reissue and not an original (it can lead to confusion) and since both tubes, original and reissue have nothing in common, it would be a good idea.
Eddie only used these because he got them cheap from the tv repair guy. He also used the variac as a volume control, the tone he got using it was a happy side effect!
The 6ca7 sound a bit warmer with a little less upper mid / low treble emphasis which I think is a good thing. Rolling a few NOS tubes through the preamp/PI might yield some good results but NOS can get a little expensive these days. I’m really enjoying following your journey in this restoration project. Thanks for sharing it with us all Jason.
I've rolled NOS PI tubes through several amps, and have have ended up liking new production JJ Ecc 803 there, ironically. They have sweet highs, and tighten the bass. A NOS Telefunnken short plate yields similar result but with peaked highs IMO.
This is one of my favorite no nonsense meat and potatoes channel.
Thank you!
Wow, that’s great to hear…tnx!
beautiful low end growl on the 6CA7's
I put a set of the same Sylvanias in my Origin 20C. I noticed the e.q. behaved completely differently and that I was happier. I tried some German Amperex EL-34's but preferred the big bottle Sylvanias. I have a Celestion Greenback to try next. Then I'll be all out of easy plug and play mods and I'll have to do your Plexi mod or just get an SV-20.😂😂😂
The difference is very very subtle. I preferred the EL34s in this comparison, they seem to have more oomph thanks to their stronger upper mids... they sound “more Marshall” 😃. We can see how Eddie chose the 6CA7s to tame that and have a “browner” result, but I don’t believe the change is worth the game, especially nowadays (even before the Russian supply problem).
Trying to source things from overseas was hard back then. You got what was at your local shop.
Yeah mate. 6ca7s all the way. Smooth.
Exactly! Tnx Ty.
I think they definitely have helped you push towards your goals. To my ears they sound more focused, compressed and brown. Great score!
6CA7 sound chunkier with a smoother top end to me.
Here in los angeles all thru late 70's and 80 's i would take my 68 50 marshall plxi to valley arts. For retube and bias every 6 months . one time he put 6ca7 tubes instead of the telefunken el 34 tubes . i took it right back and told him it sounded fu#%ed up so anyway he put in the el34 and apologised my amp sounded like a bandmaster or something i hated it but here it sounds close he bias'ed it to cold ? With 6ca7 i dont no . my 2 cents on this great show love that plxi grind cheers
Very nice comparison. I was wondering about the 6ca7’s. Listening to the guitar alone I prefer the 6ca7’s. Don’t know in a mix which ones will I prefer. The bottom end seems very similar. I think that the midrange is thicker or on the lower mid side on the 6ca7’s and on the higher mid on the el34’s. The top end is sweeter on the 6ca7’s, more extended or brighter on the el34’s. Both sound very good. I guess some people will prefer the brightness of the el34’s some will prefer the bolder sound of the 6ca7’s. On this test I prefer the 6ca7’s
Love the 6CA7 tubes! I have them in my Plexi too. Really awesome tube! Has a bite and bark to them which I prefer to the EL84s. Coupled with a couple of Mullard and GE preamp tubes it’s tone heaven! Great tones as always Jason. Have an awesome day dude!
Awesome Jase! I thought the 6ca7’s sounded a whisker warmer and less harsh if you like ... not to say the mullards were harsh though, they still sounded great! Great vid mate.
Tnx Pete!
I think the new(?) Mullards sounded best. Might the 6CA7s be worn out a little?
Well, I'm going to be the contrarian here and say that I didn't hear enough of a difference that it mattered.... but if YOU did and YOU are happy, that is all that matters. :)
I actually tried this in my '76 JMP 2203 and didn't hear much of a difference either, certainly nothing that a slight twist of the knobs didn't balance out. I'm running KT77s here... they just seem to run best in my amp which has a really hot PT.
In any case your amp sounds killer!
Fuller mids with the 6CA7. Both sound great though.
I changed out the EL-34’s for 6Ca7’s in my 87 Jubilee years ago…I like the 6Ca7’s much better….they are a little fuller,but have something special going on in the mids…They still have that 34 cut,but the highs are a little sweeter…..I think on the clips,they sound great in your Marshall…I just ordered a new set of JJ 6Ca7’s..haven’t gotten them yet,but hopefully they will sound close to the NOS ones….I think I read that EVH used them because they can take a little higher plate voltage,he was hoping they would last longer than EL-34’s….
Both sets of valves sounded great. The amp is just awesome. So I reckon preference is a matter of personal taste. I preferred the Mullards. More high midrange bite. Slightly less low end though. So, I guess when playing on your own, the USA valves sound fuller. But in a mix, the Mullards should cut through slightly better.
Yeah, that and going to 0.022 couplers….but the nostalgia!
@@HeadfirstAmps It's a magic sounding thing either way, mate. You do whatever makes you happy.
Sounds great Jason, which bright cap is in?
250pf here. It’s now got the big 4n7!!
@@HeadfirstAmps Both are great! 820r or 2,7k at high treble channel cathode?
The 6CA7s seem a little more “natural” on the clips. More solid in the lows, a smoother midrange that has some clarity to it. Those 34s had an almost fuzzy upper mid character to them by comparison. I can understand why some may like that (because it gives the appearance of having more distortion), but it’s not the most natural or clear sound by any stretch.
That's referred to as "swirl". It's a side effect guitarists tend to like of EL34 pentodes not having aligned grids. The electrons bounce around and create a wilder high-end. It can actually cause catastrophic failures from runaway bias depending on the amp design. EL34's may actually break up earlier than the 6CA7 as well. I'm not sure, but pentodes do generate stronger 3rd harmonics than power (Beam) tetrodes. That's another reason they sound clearer. They also sound more dynamic to me, and I don't think they compress near as much.
The 6CA7 certainly removed some of the fluff from the EL34. Have you ever tried E34L in comparison to EL34? Ive had them in a Stiletto in the past and thought they were a great readily available option to the standard EL34
HI - I have used the EL34L's but I haven't yet done a back to back in the same amp
Nice job on the amp Jason. Did you end up installing the 50k midrange pot?
Hey John, yes this is with a 50k mid pot. I was able to reuse a pot for the tremolo, perfect 50k vintage pot.
@@HeadfirstAmps Congratulations, it's a keeper for sure. I have one of these and it's definitely one of my best amps. I was surprised that the reissue Mullards sounded as good as they did.
But wait a minute! Glenn Fricker says a change of tubes doesn’t make a difference in tone. 🤦🏼♂️
I can move my head and make a bigger difference in tone than there is between the two. This is cork sniffing at its finest. There's a les Paul group I'm on, where they claim that brass caps on the back of the pots are warmer sounding.
Both sound good to me , I do prefer the Fatboys.if your chasing EVH Tone, Try a Sylvania 12ax7 in the first Preamp if you have a spare one lying around.
I’ve got one in there now, after this clip was taken.
The 6CA7's would be better suited if you were running a strat. They arent as spikey as the Mullard
Mullard sounds good,but to me a bit brittle. 6ca7 sounds "fuller" and and less hars whitout loosing too much topend.
Play a early 60”s Gibson amp. It will change the way you think about the Marshall and a 68 as well.
Indeed, you'll really appreciate a real Marshall after playing that p.o.s!
Hahaha. Funny.
You should make it clear in the video that Mullards is a reissue and not an original (it can lead to confusion) and since both tubes, original and reissue have nothing in common, it would be a good idea.
I preferred the Mullard reissues!