Hi All,
I've got a pair of output transformers of an old Pioneer SM83 amplifier.
I would like to use 'm with another tube than the 7189 (or EL84M) they were designed for.
The PP-7189 delivers 18W at 400V so I think I can use some beefier tubes than the EL84.
Any suggestions? 6L6 - 807 ???
Thanks,
Jim
I've got a pair of output transformers of an old Pioneer SM83 amplifier.
I would like to use 'm with another tube than the 7189 (or EL84M) they were designed for.
The PP-7189 delivers 18W at 400V so I think I can use some beefier tubes than the EL84.
Any suggestions? 6L6 - 807 ???
Thanks,
Jim
Hi jim ,
First of all , you have to say if the output transformers are wound for
UL operation ( 5 primary taps ) or for Pentode operation ( 3 primary taps ) , because the impedance plate to plate , are very different case
to case ( aprox. 40% ) .
If you know how to do it , calculate the TURNS RATIO : Primary plate to
plate versus secondary 8 ohms output and report the values .
Then we can recommend the best replacement .
Regards ,
Carlos
First of all , you have to say if the output transformers are wound for
UL operation ( 5 primary taps ) or for Pentode operation ( 3 primary taps ) , because the impedance plate to plate , are very different case
to case ( aprox. 40% ) .
If you know how to do it , calculate the TURNS RATIO : Primary plate to
plate versus secondary 8 ohms output and report the values .
Then we can recommend the best replacement .
Regards ,
Carlos
Since you have 18W xfmrs with an Raa= 8.0K, these would be ideal for use with 6V6s.
Operate Class AB1, Vpp= 285Vdc, Ip= 70mA, Vgk= -19Vdc. This will give 14W with 3.5% THD before adding feedback. Add local feedback + gNFB and that would perform quite well. 6V6s get considerable praise for sonic excellence.
Operate Class AB1, Vpp= 285Vdc, Ip= 70mA, Vgk= -19Vdc. This will give 14W with 3.5% THD before adding feedback. Add local feedback + gNFB and that would perform quite well. 6V6s get considerable praise for sonic excellence.
Hi JIM ,
First of all , I think that there is a little mistake , because 7189’s , connected as push-pull pentodes , with +B 400 V , and loaded
with 8000 ohms plate to plate , can deliver more than 25 Watts ,
with 4% THD , and not “only” 18 Watts , as you said .
So I think that , your output tranny can “hand” more than 24 Watts , without core saturation.
I’ll gave to you many suggestions , as follows :
6V6 – 1% THD
PP – Class AB1 – 12 Watts
Plate voltage : 350 VDC Screen voltage : 340 VDC
Max. at each grid control : 13 Volts RMS ( signal level )
COMMON cathode resistor : 250 ohms x 10 Watts
6973 – 2% THD
PP – Class AB – 24 Watts
Plate voltage : 400 VDC Screen voltage : 290 VDC
Control grid : ( - ) 25 VDC
Fixed bias
6BQ5 / EL84 – 4% THD
PP – Class AB1 – 17 Watts
Plate voltage : 300 VDC Screen voltage : 290 VDC
Max. at each grid control : 10 Volts RMS ( signal level )
COMMON cathode resistor : 130 ohms x 15 Watts
6CZ5 – 1% THD
PP – Class AB1 – 22 watts
Plate voltage : 350 VDC Screen voltage : 280 VDC
Control grid : ( - ) 23.5 VDC
Fixed bias
6L6 GB / GC / WXT , etc. – 2% THD
PP – Class AB1 – about 24 Watts
Plate voltage : 360 VDC Screen voltage : 270 VDC
Control Grid : ( - ) 22.5 VDC
Fixed bias
Note : In this case , the ideal load would be 6600–7000 ohms plate to plate , but 8000 ohms still works too .
Note 1 : The values of THD ( harmonic distortion ) are without
negative feedback , with NFB , the values will lower 10
times or more .
Note 2 : KT66 , 7591 , 807 and 5881 , need to be running under
Ultra Linear operation condition , to be loading with
8000 ohms plate to plate .
Note 3 : 6CA7 / EL34 can deliver more than 25 Watts , so , your
output tranny , will have core saturation and distortion.
Any doubt , feel free to ask ,
Regards ,
Carlos
First of all , I think that there is a little mistake , because 7189’s , connected as push-pull pentodes , with +B 400 V , and loaded
with 8000 ohms plate to plate , can deliver more than 25 Watts ,
with 4% THD , and not “only” 18 Watts , as you said .
So I think that , your output tranny can “hand” more than 24 Watts , without core saturation.
I’ll gave to you many suggestions , as follows :
6V6 – 1% THD
PP – Class AB1 – 12 Watts
Plate voltage : 350 VDC Screen voltage : 340 VDC
Max. at each grid control : 13 Volts RMS ( signal level )
COMMON cathode resistor : 250 ohms x 10 Watts
6973 – 2% THD
PP – Class AB – 24 Watts
Plate voltage : 400 VDC Screen voltage : 290 VDC
Control grid : ( - ) 25 VDC
Fixed bias
6BQ5 / EL84 – 4% THD
PP – Class AB1 – 17 Watts
Plate voltage : 300 VDC Screen voltage : 290 VDC
Max. at each grid control : 10 Volts RMS ( signal level )
COMMON cathode resistor : 130 ohms x 15 Watts
6CZ5 – 1% THD
PP – Class AB1 – 22 watts
Plate voltage : 350 VDC Screen voltage : 280 VDC
Control grid : ( - ) 23.5 VDC
Fixed bias
6L6 GB / GC / WXT , etc. – 2% THD
PP – Class AB1 – about 24 Watts
Plate voltage : 360 VDC Screen voltage : 270 VDC
Control Grid : ( - ) 22.5 VDC
Fixed bias
Note : In this case , the ideal load would be 6600–7000 ohms plate to plate , but 8000 ohms still works too .
Note 1 : The values of THD ( harmonic distortion ) are without
negative feedback , with NFB , the values will lower 10
times or more .
Note 2 : KT66 , 7591 , 807 and 5881 , need to be running under
Ultra Linear operation condition , to be loading with
8000 ohms plate to plate .
Note 3 : 6CA7 / EL34 can deliver more than 25 Watts , so , your
output tranny , will have core saturation and distortion.
Any doubt , feel free to ask ,
Regards ,
Carlos
refference said:
How do you figure this? The 807 and 6L6 are the same VT in different bottles. Same Q Points and everything. The 807/6L6 are not good for ultralinear (which I don't like anyway) since this VT was intended to run with Vpp up and Vsgsg held down. You don't get much with them in ultralinear (~10W). You bust the R(L) spec that much, and you aren't going to get ~2.0% THD anymore.
Hi JIM ,
First of all I want to say to Miles Prower , that 6L6 and 807
“ARE NOT THE SAME TUBE IN DIFFERENT BOTTLES”
They have some common characteristics , but you NEVER
can say that they are “the same tube” , as you said .
Second :
I NEVER affirmed on my previous post , that 6L6 and 807
are good tubes for UL operation , you did not understand .
What I had said , was the following :
“The 807 and others , MUST to be in a UL circuit , to work fine
with a load of 8000 ohms , ” ( 8000 ohms is the input impedance
plate to plate of JIM’s output tranny , and as he said it is only for
pentode connection , then , 807 and others , are not useful tubes
for him )
JIM ,
All technical characteristcs and suggestions that I had sent
on my previous post , has like base , the following bibliography ;
RCA 28 – Receiving Tube Manual
SYLVANIA – Technical Manual - 1954 Edition / 1958 Edition and
1970 Edition
Radio Amateur’s Handbook – 1939 Edition and 1952 Edition
Regards ,
Carlos
First of all I want to say to Miles Prower , that 6L6 and 807
“ARE NOT THE SAME TUBE IN DIFFERENT BOTTLES”
They have some common characteristics , but you NEVER
can say that they are “the same tube” , as you said .
Second :
I NEVER affirmed on my previous post , that 6L6 and 807
are good tubes for UL operation , you did not understand .
What I had said , was the following :
“The 807 and others , MUST to be in a UL circuit , to work fine
with a load of 8000 ohms , ” ( 8000 ohms is the input impedance
plate to plate of JIM’s output tranny , and as he said it is only for
pentode connection , then , 807 and others , are not useful tubes
for him )
JIM ,
All technical characteristcs and suggestions that I had sent
on my previous post , has like base , the following bibliography ;
RCA 28 – Receiving Tube Manual
SYLVANIA – Technical Manual - 1954 Edition / 1958 Edition and
1970 Edition
Radio Amateur’s Handbook – 1939 Edition and 1952 Edition
Regards ,
Carlos
refference said:
Not just "some common characteristics", but identical Q Points, power out, and THD figures. In another thread, Tubelab said he took apart both types and found no internal difference. Just a couple of nights ago, I also found a schematic for a CW xmtr that used a 6L6 as the final in a circuit identical to one used for 807s.
You also said:
Not word one there about UL, implying that he could use the 6L6, but not the 807.
Hi JIM ,
The 6L6 and 807 ARE NOT THE SAME TUBE !!!
They can have A LOT of common characteristics , but they have too :
Different “optimum” operation points
Different harmonic distortion ( if operated at differents points )
Different SOUND
Different “maximum” ratings ( voltage and current )
Different TONAL richness
Etc, etc .
The confusion was born , because they were introduced in
the 30’s ( before WW II ) with the designation of RECEIVING
TUBES , so it looks like obvious that both of them will work very
fine inside a CW or any RF transmiter or receiver , but inside
any AF amplifier the SOUND ( sound is the goal of this forum ),
will certainly be different .
Regards ,
Carlos
The 6L6 and 807 ARE NOT THE SAME TUBE !!!
They can have A LOT of common characteristics , but they have too :
Different “optimum” operation points
Different harmonic distortion ( if operated at differents points )
Different SOUND
Different “maximum” ratings ( voltage and current )
Different TONAL richness
Etc, etc .
The confusion was born , because they were introduced in
the 30’s ( before WW II ) with the designation of RECEIVING
TUBES , so it looks like obvious that both of them will work very
fine inside a CW or any RF transmiter or receiver , but inside
any AF amplifier the SOUND ( sound is the goal of this forum ),
will certainly be different .
Regards ,
Carlos
Dear friends Miles Prower and Coresta ,
ALL information that I’m writing here , has like base the most
reliable source that we can really trust : THE TECHNICAL MANUALS wrote by the GENERAL ELECTRIC , RADIO CORPORATION OF AMERICA AND GTE & SYLVANIA
engineers . I believe that we can trust them , or you think not ??
When they engineered and created the tubes , they also publi-
shed the technical manuals , where they gave all the information
necessary to operate those tubes , inside their limits , trying to
get the BEST PERFORMANCE , regarding serviceability , maximum lifetime , reliability , and ( again ) the best performance .
If you or any people run those tubes within another parameters ,
obviously that they will run . But one or more of those compro –
mises above listed , will be drew to another NOT CONVENIENT
point .
Then , you can run 6L6 within the 807’parameters , or vice-versa it is obvious. BUT you will not get the BEST of anyone .
So the 6L6 and 807 ARE NOT THE SAME TUBE !!
See the table that I listed below !!! Analyze it carefully and say if
807 and 6L6 are the same tube !!! ???
NOTE : This table was done with the help of the bibliography
above listed . I’ll repeat : The UNIQUE RELIABLE source , the
rest are EXPERIMENTAL WORKS .
TYPICAL OPERATION
Plate (V) Grid (V) Ip (mA) Load (ohms) Power (W)
6L6 PP-AB1 360 - 22.5 93 6600 27
807 PP-AB1 400 - 45 63 3000 15
6L6 PP-AB2 360 - 18 82 6000 32
807 PP-AB2 600 - 30 62 6400 80
Absolute maximum plate voltage – 6L6 – 360 Volts
807 - 600 Volts
Maximum plate dissipation - 6L6 – 19 Watts
807 - 25 Watts
Coresta , as you can see , I’m not talking about “personal tastes” .
It’s mathematical , not personal and not mythological .
After you have seen that list , it looks like characteristics of two
eletricaly identical tubes ???? I do not think so !!!
You can say that 5881 , 6L6 and 1614 are eletricaly identicals ,
6669 , 6AQ5 and 6V6 are eletricaly identicals , 7025 and 12AX7
are eletricaly identicals , ECC 189 , 6DJ8 , ECC88 and 6922 are
eletricaly identicals , 6955 , 12AU7 , 6189 and 5814 are eletricaly
identicals , EF86 , 6267 and 5879 are eletricaly identicals , and
much more .
Hi JIM , I want to hear from you !!!
Regards for all ,
Carlos
ALL information that I’m writing here , has like base the most
reliable source that we can really trust : THE TECHNICAL MANUALS wrote by the GENERAL ELECTRIC , RADIO CORPORATION OF AMERICA AND GTE & SYLVANIA
engineers . I believe that we can trust them , or you think not ??
When they engineered and created the tubes , they also publi-
shed the technical manuals , where they gave all the information
necessary to operate those tubes , inside their limits , trying to
get the BEST PERFORMANCE , regarding serviceability , maximum lifetime , reliability , and ( again ) the best performance .
If you or any people run those tubes within another parameters ,
obviously that they will run . But one or more of those compro –
mises above listed , will be drew to another NOT CONVENIENT
point .
Then , you can run 6L6 within the 807’parameters , or vice-versa it is obvious. BUT you will not get the BEST of anyone .
So the 6L6 and 807 ARE NOT THE SAME TUBE !!
See the table that I listed below !!! Analyze it carefully and say if
807 and 6L6 are the same tube !!! ???
NOTE : This table was done with the help of the bibliography
above listed . I’ll repeat : The UNIQUE RELIABLE source , the
rest are EXPERIMENTAL WORKS .
TYPICAL OPERATION
Plate (V) Grid (V) Ip (mA) Load (ohms) Power (W)
6L6 PP-AB1 360 - 22.5 93 6600 27
807 PP-AB1 400 - 45 63 3000 15
6L6 PP-AB2 360 - 18 82 6000 32
807 PP-AB2 600 - 30 62 6400 80
Absolute maximum plate voltage – 6L6 – 360 Volts
807 - 600 Volts
Maximum plate dissipation - 6L6 – 19 Watts
807 - 25 Watts
Coresta , as you can see , I’m not talking about “personal tastes” .
It’s mathematical , not personal and not mythological .
After you have seen that list , it looks like characteristics of two
eletricaly identical tubes ???? I do not think so !!!
You can say that 5881 , 6L6 and 1614 are eletricaly identicals ,
6669 , 6AQ5 and 6V6 are eletricaly identicals , 7025 and 12AX7
are eletricaly identicals , ECC 189 , 6DJ8 , ECC88 and 6922 are
eletricaly identicals , 6955 , 12AU7 , 6189 and 5814 are eletricaly
identicals , EF86 , 6267 and 5879 are eletricaly identicals , and
much more .
Hi JIM , I want to hear from you !!!
Regards for all ,
Carlos
refference said:
Hi Carlos, the max 600v (and 6BG6) rating of the 807 comes from the upper cap . 6AQ5 is not a 6V6 , ecc189 is not a 6dj8 (semi remote tube) , 6267and 5879 are not identical
But experiments with 807 gave even better results swapping the 6L6 , in my humble opinion Cheers, PierreHi coresta ,
Doing the necessary mechanical changes ( obvious ) ,
try to make the following replacement :
6V6 instead 6AQ5 and vice-versa
ECC189 intead 6DJ8 and vice-versa
6267 instead 5879 and vice-versa
And you will see that all changes work very , very fine ,
excepting ( obvious ) little changes in personal tastes.
I can affirm to you that all the changes above listed ,
will work “A LOT” BETTER , than the 6L6 versus 807.
My only intention , is to transmit to all the people , a
bit of my humble knowledge , acquired over 35 years ,
working with our sweet vacuum tubes .
Best regards ,
Carlos
Hi JIM ,
All of us want to hear from you , where are you ?
Doing the necessary mechanical changes ( obvious ) ,
try to make the following replacement :
6V6 instead 6AQ5 and vice-versa
ECC189 intead 6DJ8 and vice-versa
6267 instead 5879 and vice-versa
And you will see that all changes work very , very fine ,
excepting ( obvious ) little changes in personal tastes.
I can affirm to you that all the changes above listed ,
will work “A LOT” BETTER , than the 6L6 versus 807.
My only intention , is to transmit to all the people , a
bit of my humble knowledge , acquired over 35 years ,
working with our sweet vacuum tubes .
Best regards ,
Carlos
Hi JIM ,
All of us want to hear from you , where are you ?
Hi all,
If it is possible to join in here without being part of or generating a shoot-out (don't know how well you guys shoot - might only wound instead of kill me!)
I have it in an old article (under the auspices of RCA) on the development of the 6L6, that that came about in March 1936, developed by a Mr Schade and colleauges of RCA. (It followed the 42 tube of some 3,5 years earlier). They followed the concept of the virtual cathode illustrated in England somewhat earlier, but also introduced the aligned g1/g2, beam plates, etc.
It was an immediate hit, also tried as a transmitting tube. This lead to the 807 in order to be able to apply a higher anode voltage, but limiting the Vg2 in order to keep guys from destroying it by using too high a Vg2 together with a high Va. At that time at least, the innards were identical; in fact, on a 1952 data sheet one is referred to the 6L6 for characteristics of the 807. The 807 was the direct ancestor of the 6146. In 1946 there emerged the 6BG6G, also a repackaged 6L6, as a sweep tube..... and so forth.
Lie they. lie I!
Carlos, your max. voltage ratings for the 6L6 seem to be a little outdated; they have been upgraded already before 1966 in the the 6L6GC to Va = 500V and Vg2 = 450V (500V in UL), mainly because of a different pattern used in the supporting mica wafers. Also the reportedly rugged 5881 at Pa = 23W was then available at Va = Vg2 = 400V. Indeed you are technically correct for the early 6L6, but I thought they are no longer available, having been listed as replacement/obsolete already in 1970.
As such the 6L6 (-GC and other equivalents) are very suitable for use in UL. Currently they often replace the KT66 (they are within 10%) because of the higher Pa. The Russians even package them marked KT66/6L6GC on the glass envelope - although we know they are often a little free with their designations.
This not to distract from the usual excellent advice given by Carlos, but I though a little history might be in order. Not to say what folks do these days - I find 6L6s with oval anodes, box anodes and what not. It is a little hard to believe they are all the same. (Also to respectfully add, I am not into the "tube sound" business - if folks claim to hear sonic differences, that is their right. To each his own.)
Regards.
If it is possible to join in here without being part of or generating a shoot-out (don't know how well you guys shoot - might only wound instead of kill me!)
I have it in an old article (under the auspices of RCA) on the development of the 6L6, that that came about in March 1936, developed by a Mr Schade and colleauges of RCA. (It followed the 42 tube of some 3,5 years earlier). They followed the concept of the virtual cathode illustrated in England somewhat earlier, but also introduced the aligned g1/g2, beam plates, etc.
It was an immediate hit, also tried as a transmitting tube. This lead to the 807 in order to be able to apply a higher anode voltage, but limiting the Vg2 in order to keep guys from destroying it by using too high a Vg2 together with a high Va. At that time at least, the innards were identical; in fact, on a 1952 data sheet one is referred to the 6L6 for characteristics of the 807. The 807 was the direct ancestor of the 6146. In 1946 there emerged the 6BG6G, also a repackaged 6L6, as a sweep tube..... and so forth.
Lie they. lie I!
Carlos, your max. voltage ratings for the 6L6 seem to be a little outdated; they have been upgraded already before 1966 in the the 6L6GC to Va = 500V and Vg2 = 450V (500V in UL), mainly because of a different pattern used in the supporting mica wafers. Also the reportedly rugged 5881 at Pa = 23W was then available at Va = Vg2 = 400V. Indeed you are technically correct for the early 6L6, but I thought they are no longer available, having been listed as replacement/obsolete already in 1970.
As such the 6L6 (-GC and other equivalents) are very suitable for use in UL. Currently they often replace the KT66 (they are within 10%) because of the higher Pa. The Russians even package them marked KT66/6L6GC on the glass envelope - although we know they are often a little free with their designations.
This not to distract from the usual excellent advice given by Carlos, but I though a little history might be in order. Not to say what folks do these days - I find 6L6s with oval anodes, box anodes and what not. It is a little hard to believe they are all the same. (Also to respectfully add, I am not into the "tube sound" business - if folks claim to hear sonic differences, that is their right. To each his own.)
Regards.
Try them Carlos
Ok, here I am again...
Sorry for this late reply, just returned from my honeymoon on Gran Canaria...
From what I read in this thread I think I'm going to play save and
use some nice Radiotron 6V6G's with these trannies.
But the 807 looks so much cooler....(or so much hotter in this case).
A few years ago I used triode'd pp807 (as per datasheet) with an EL84 output transformer, power output was about 7W but with sooo sweet sound.
So....what's it gonna be ???
Jim
Sorry for this late reply, just returned from my honeymoon on Gran Canaria...
From what I read in this thread I think I'm going to play save and
use some nice Radiotron 6V6G's with these trannies.
But the 807 looks so much cooler....(or so much hotter in this case).
A few years ago I used triode'd pp807 (as per datasheet) with an EL84 output transformer, power output was about 7W but with sooo sweet sound.
So....what's it gonna be ???
Jim
The 6L6 - 807 debate has been going on for some time. I have read plenty of information that supports both sides of this argument. I will just offer a few things that I know. I have a good collection of electronics books from the vacuum tube era, mostly college level engineering texts, and some US Army training books. From what I have gathered the 6L6 appears to have come first. I found a picture of the metal 6L6 in a textbook that was printed in 1938. The glass version 6L6G, was offered at about the same time. The 6L6GA was an improved version with better power handling and voltage capabillities. The 6L6GB had further improvements. It was from this tube that the 807 and 6BG6 were made.
I have a warehouse full of WWII era vacuum tubes. Many were damaged due to mishandling by the previous owners and the moving contractors. I have examined the guts of several 807's, 1625's 6BG6's and 6L6's of various flavors. In EVERY case the 807's, 6BG6's and 6L6GB's FROM THE SAME MANUFACTURER AND VINTAGE have the same internal construction. You will find differences between tubes of different manufacturer and date, but that is true of any tube.
Note, I said 6L6GB NOT 6L6 or 6L6GA. The original 6L6 metal or the 6L6G or the 6L6GA are not the same tube and will NOT take the power or voltage that the 6L6GB - 807 - 1625 - 6BG6 can handle. The 6L6GC is NOT the same tube either. It has an improved plate to handle 30 watts.
The published specifications differ for two reasons. First the use of a plate cap in the 807,1625, and 6BG6 removes the limitations imposed by the spacing between pin3 (plate) and pin 2 (filament). This is the limiting factor on a 6L6, and they will ARC if abused. Another difference is the fact that RCA published the 6L6 and 6L6GB ratings as "design center values" while the 807 and 6L6GC were rated in "design maximum values".
The 6L6 was intended for PA and HiFi operation, while the 807 was intended for use as a modulator, or plate modulated RF amplifier, and the 6BG6 was intended for use as a horizontal output tube in TV sets. Therefore the recommendations for "typical operation" were different.
Any of these tubes would make a decent amplifier, and I am sure that you could find diferences in the sound between different flavors of 807's or 6L6's. There were so many vendors making both tubes in the WWII era it is hard to tell who really made it from the brand name on the tube. Some are excellent, and some are not.
With an 8K ohm transformer the 6V6 is the "textbook" answer and would make a good sounding amplifier. I have always done things a bit diferently, so I offer a unique possibility. You think that 807's would look cool, so build a push pull amp with 807's, run them triode connected class A.
I ran through a Tube Cad simulation. It showed that you could build a Class A push pull triode mode amp using cathode bias (200 ohm cathode resistor) with 375 volts B+ and get 18 watts at 1.7 % distortion. The cathode resistor must be at least 5 watts, bypassed with at least 500uF 50 volt cap. Idle current would be 66 mA per tube.
Don't want to push the tubes that hard? Use a slightly higher B+ voltage (400 volts) and a 390 ohm cathode resistor. This makes a class AB amplifier of 20 watts with 2.5 % distortion.
There are zillions of possible combinations that are possible with your transformers. Decide which tubes that you want to use, then, if you have a power transformer already. Figure out how much B+ you have. Now you only have a few thousand possibilities.
I have a warehouse full of WWII era vacuum tubes. Many were damaged due to mishandling by the previous owners and the moving contractors. I have examined the guts of several 807's, 1625's 6BG6's and 6L6's of various flavors. In EVERY case the 807's, 6BG6's and 6L6GB's FROM THE SAME MANUFACTURER AND VINTAGE have the same internal construction. You will find differences between tubes of different manufacturer and date, but that is true of any tube.
Note, I said 6L6GB NOT 6L6 or 6L6GA. The original 6L6 metal or the 6L6G or the 6L6GA are not the same tube and will NOT take the power or voltage that the 6L6GB - 807 - 1625 - 6BG6 can handle. The 6L6GC is NOT the same tube either. It has an improved plate to handle 30 watts.
The published specifications differ for two reasons. First the use of a plate cap in the 807,1625, and 6BG6 removes the limitations imposed by the spacing between pin3 (plate) and pin 2 (filament). This is the limiting factor on a 6L6, and they will ARC if abused. Another difference is the fact that RCA published the 6L6 and 6L6GB ratings as "design center values" while the 807 and 6L6GC were rated in "design maximum values".
The 6L6 was intended for PA and HiFi operation, while the 807 was intended for use as a modulator, or plate modulated RF amplifier, and the 6BG6 was intended for use as a horizontal output tube in TV sets. Therefore the recommendations for "typical operation" were different.
Any of these tubes would make a decent amplifier, and I am sure that you could find diferences in the sound between different flavors of 807's or 6L6's. There were so many vendors making both tubes in the WWII era it is hard to tell who really made it from the brand name on the tube. Some are excellent, and some are not.
With an 8K ohm transformer the 6V6 is the "textbook" answer and would make a good sounding amplifier. I have always done things a bit diferently, so I offer a unique possibility. You think that 807's would look cool, so build a push pull amp with 807's, run them triode connected class A.
I ran through a Tube Cad simulation. It showed that you could build a Class A push pull triode mode amp using cathode bias (200 ohm cathode resistor) with 375 volts B+ and get 18 watts at 1.7 % distortion. The cathode resistor must be at least 5 watts, bypassed with at least 500uF 50 volt cap. Idle current would be 66 mA per tube.
Don't want to push the tubes that hard? Use a slightly higher B+ voltage (400 volts) and a 390 ohm cathode resistor. This makes a class AB amplifier of 20 watts with 2.5 % distortion.
There are zillions of possible combinations that are possible with your transformers. Decide which tubes that you want to use, then, if you have a power transformer already. Figure out how much B+ you have. Now you only have a few thousand possibilities.
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