Hi, I am contemplating of getting a tube preamp for pairing with SS
Amp. The preamp that I am interested offer 2 different tubes choice-
12SN7 or 6SN7 . I wonder which one of them would deliver fuller(more
full-bodied)sound ? Any sonic advantages for one over the other ??
Your explaination and suggestions is highly appreciated and thanks in
advance
Simon

simonleemd wrote:

Hi, I am contemplating of getting a tube preamp for pairing with SS
Amp. The preamp that I am interested offer 2 different tubes choice-
12SN7 or 6SN7 . I wonder which one of them would deliver fuller(more
full-bodied)sound ? Any sonic advantages for one over the other ??
Your explaination and suggestions is highly appreciated and thanks in
advance
Simon

I believe the only difference is the heater voltage. So as long
as you heat the 12.6V version with 12.6V and the 6.3V version with
6.3V, they should be the same (except for whatever possible VERY
small difference, e.g. in hum, might result from the different
potentials between heater and cathode).

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

simonleemd wrote:

Hi, I am contemplating of getting a tube preamp for pairing with SS
Amp. The preamp that I am interested offer 2 different tubes choice-
12SN7 or 6SN7 . I wonder which one of them would deliver fuller(more
full-bodied)sound ? Any sonic advantages for one over the other ??
Your explaination and suggestions is highly appreciated and thanks in
advance
Simon

I believe the only difference is the heater voltage. So as long
as you heat the 12.6V version with 12.6V and the 6.3V version with
6.3V, they should be the same (except for whatever possible VERY
small difference, e.g. in hum, might result from the different
potentials between heater and cathode).

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

simonleemd wrote:

Hi, I am contemplating of getting a tube preamp for pairing with SS
Amp. The preamp that I am interested offer 2 different tubes choice-
12SN7 or 6SN7 . I wonder which one of them would deliver fuller(more
full-bodied)sound ? Any sonic advantages for one over the other ??
Your explaination and suggestions is highly appreciated and thanks in
advance
Simon

I believe the only difference is the heater voltage. So as long
as you heat the 12.6V version with 12.6V and the 6.3V version with
6.3V, they should be the same (except for whatever possible VERY
small difference, e.g. in hum, might result from the different
potentials between heater and cathode).

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

Ah, tubes, my past is back in vogue.

The obvious difference between the two is the heater voltages.

The RCA Tube Manual says they are the same but, the plate voltages are
different, 90 vs. 250, plate resistance , 6700 vs. 7700 ohms,
transconductance 300 vs. 2600 umhos, grid voltage for a plate current of 10
uA 7 vs. 18 volts, these being some items for use as a Class A amplifier.

The 12SN7 would appear to be a beefier tube in use in a Vertical Deflection
Amplifier.

The 12SN7 probably has a higher capability to generate electrons at the
cathode than the 6SN7, so it can probably produce more voltage swing at the
plate.

rtt


"CJT" wrote in message
...
simonleemd wrote:

Hi, I am contemplating of getting a tube preamp for pairing with SS
Amp. The preamp that I am interested offer 2 different tubes choice-
12SN7 or 6SN7 . I wonder which one of them would deliver fuller(more
full-bodied)sound ? Any sonic advantages for one over the other ??
Your explaination and suggestions is highly appreciated and thanks in
advance
Simon

I believe the only difference is the heater voltage. So as long
as you heat the 12.6V version with 12.6V and the 6.3V version with
6.3V, they should be the same (except for whatever possible VERY
small difference, e.g. in hum, might result from the different
potentials between heater and cathode).

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

Ah, tubes, my past is back in vogue.

The obvious difference between the two is the heater voltages.

The RCA Tube Manual says they are the same but, the plate voltages are
different, 90 vs. 250, plate resistance , 6700 vs. 7700 ohms,
transconductance 300 vs. 2600 umhos, grid voltage for a plate current of 10
uA 7 vs. 18 volts, these being some items for use as a Class A amplifier.

The 12SN7 would appear to be a beefier tube in use in a Vertical Deflection
Amplifier.

The 12SN7 probably has a higher capability to generate electrons at the
cathode than the 6SN7, so it can probably produce more voltage swing at the
plate.

rtt


"CJT" wrote in message
...
simonleemd wrote:

Hi, I am contemplating of getting a tube preamp for pairing with SS
Amp. The preamp that I am interested offer 2 different tubes choice-
12SN7 or 6SN7 . I wonder which one of them would deliver fuller(more
full-bodied)sound ? Any sonic advantages for one over the other ??
Your explaination and suggestions is highly appreciated and thanks in
advance
Simon

I believe the only difference is the heater voltage. So as long
as you heat the 12.6V version with 12.6V and the 6.3V version with
6.3V, they should be the same (except for whatever possible VERY
small difference, e.g. in hum, might result from the different
potentials between heater and cathode).

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

Ah, tubes, my past is back in vogue.

The obvious difference between the two is the heater voltages.

The RCA Tube Manual says they are the same but, the plate voltages are
different, 90 vs. 250, plate resistance , 6700 vs. 7700 ohms,
transconductance 300 vs. 2600 umhos, grid voltage for a plate current of 10
uA 7 vs. 18 volts, these being some items for use as a Class A amplifier.

The 12SN7 would appear to be a beefier tube in use in a Vertical Deflection
Amplifier.

The 12SN7 probably has a higher capability to generate electrons at the
cathode than the 6SN7, so it can probably produce more voltage swing at the
plate.

rtt


"CJT" wrote in message
...
simonleemd wrote:

Hi, I am contemplating of getting a tube preamp for pairing with SS
Amp. The preamp that I am interested offer 2 different tubes choice-
12SN7 or 6SN7 . I wonder which one of them would deliver fuller(more
full-bodied)sound ? Any sonic advantages for one over the other ??
Your explaination and suggestions is highly appreciated and thanks in
advance
Simon

I believe the only difference is the heater voltage. So as long
as you heat the 12.6V version with 12.6V and the 6.3V version with
6.3V, they should be the same (except for whatever possible VERY
small difference, e.g. in hum, might result from the different
potentials between heater and cathode).

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

"Richard Tomkins" wrote in message ws.com...
Ah, tubes, my past is back in vogue.

The obvious difference between the two is the heater voltages.

The RCA Tube Manual says they are the same but, the plate voltages are
different, 90 vs. 250, plate resistance , 6700 vs. 7700 ohms,
transconductance 300 vs. 2600 umhos, grid voltage for a plate current of 10
uA 7 vs. 18 volts, these being some items for use as a Class A amplifier.

The 12SN7 would appear to be a beefier tube in use in a Vertical Deflection
Amplifier.

The 12SN7 probably has a higher capability to generate electrons at the
cathode than the 6SN7, so it can probably produce more voltage swing at the
plate.

rtt

snip

You missed the fine print in that RCA book.
The differences you cited aren't between the 6 and the 12, they are
between the two independent triodes inside the glass envelope. RCA
refers to them as "Unit No. 1" and "Unit No. 2". It's right above the
"Direct Interelectrode Capacitances" line.
It is a little confusingly laid out, due to RCA's attempts to get as
much info into the book as possible while remaining at a manageable
size.

"Richard Tomkins" wrote in message ws.com...
Ah, tubes, my past is back in vogue.

The obvious difference between the two is the heater voltages.

The RCA Tube Manual says they are the same but, the plate voltages are
different, 90 vs. 250, plate resistance , 6700 vs. 7700 ohms,
transconductance 300 vs. 2600 umhos, grid voltage for a plate current of 10
uA 7 vs. 18 volts, these being some items for use as a Class A amplifier.

The 12SN7 would appear to be a beefier tube in use in a Vertical Deflection
Amplifier.

The 12SN7 probably has a higher capability to generate electrons at the
cathode than the 6SN7, so it can probably produce more voltage swing at the
plate.

rtt

snip

You missed the fine print in that RCA book.
The differences you cited aren't between the 6 and the 12, they are
between the two independent triodes inside the glass envelope. RCA
refers to them as "Unit No. 1" and "Unit No. 2". It's right above the
"Direct Interelectrode Capacitances" line.
It is a little confusingly laid out, due to RCA's attempts to get as
much info into the book as possible while remaining at a manageable
size.

"Richard Tomkins" wrote in message ws.com...
Ah, tubes, my past is back in vogue.

The obvious difference between the two is the heater voltages.

The RCA Tube Manual says they are the same but, the plate voltages are
different, 90 vs. 250, plate resistance , 6700 vs. 7700 ohms,
transconductance 300 vs. 2600 umhos, grid voltage for a plate current of 10
uA 7 vs. 18 volts, these being some items for use as a Class A amplifier.

The 12SN7 would appear to be a beefier tube in use in a Vertical Deflection
Amplifier.

The 12SN7 probably has a higher capability to generate electrons at the
cathode than the 6SN7, so it can probably produce more voltage swing at the
plate.

rtt

snip

You missed the fine print in that RCA book.
The differences you cited aren't between the 6 and the 12, they are
between the two independent triodes inside the glass envelope. RCA
refers to them as "Unit No. 1" and "Unit No. 2". It's right above the
"Direct Interelectrode Capacitances" line.
It is a little confusingly laid out, due to RCA's attempts to get as
much info into the book as possible while remaining at a manageable
size.

Darn, and I thought I was doing someone a good favour.

In any event, then, the RCA manual did initially say they were the same and
that is what I did recite up front.

I'd still believe that the 12Volt tube can produce a greater number of
electrons and thus would have better gain?

rtt


"unitron" wrote in message
om...
"Richard Tomkins" wrote in message
ws.com...
Ah, tubes, my past is back in vogue.

The obvious difference between the two is the heater voltages.

The RCA Tube Manual says they are the same but, the plate voltages are
different, 90 vs. 250, plate resistance , 6700 vs. 7700 ohms,
transconductance 300 vs. 2600 umhos, grid voltage for a plate current of
10
uA 7 vs. 18 volts, these being some items for use as a Class A
amplifier.

The 12SN7 would appear to be a beefier tube in use in a Vertical
Deflection
Amplifier.

The 12SN7 probably has a higher capability to generate electrons at the
cathode than the 6SN7, so it can probably produce more voltage swing at
the
plate.

rtt

snip

You missed the fine print in that RCA book.
The differences you cited aren't between the 6 and the 12, they are
between the two independent triodes inside the glass envelope. RCA
refers to them as "Unit No. 1" and "Unit No. 2". It's right above the
"Direct Interelectrode Capacitances" line.
It is a little confusingly laid out, due to RCA's attempts to get as
much info into the book as possible while remaining at a manageable
size.

Darn, and I thought I was doing someone a good favour.

In any event, then, the RCA manual did initially say they were the same and
that is what I did recite up front.

I'd still believe that the 12Volt tube can produce a greater number of
electrons and thus would have better gain?

rtt


"unitron" wrote in message
om...
"Richard Tomkins" wrote in message
ws.com...
Ah, tubes, my past is back in vogue.

The obvious difference between the two is the heater voltages.

The RCA Tube Manual says they are the same but, the plate voltages are
different, 90 vs. 250, plate resistance , 6700 vs. 7700 ohms,
transconductance 300 vs. 2600 umhos, grid voltage for a plate current of
10
uA 7 vs. 18 volts, these being some items for use as a Class A
amplifier.

The 12SN7 would appear to be a beefier tube in use in a Vertical
Deflection
Amplifier.

The 12SN7 probably has a higher capability to generate electrons at the
cathode than the 6SN7, so it can probably produce more voltage swing at
the
plate.

rtt

snip

You missed the fine print in that RCA book.
The differences you cited aren't between the 6 and the 12, they are
between the two independent triodes inside the glass envelope. RCA
refers to them as "Unit No. 1" and "Unit No. 2". It's right above the
"Direct Interelectrode Capacitances" line.
It is a little confusingly laid out, due to RCA's attempts to get as
much info into the book as possible while remaining at a manageable
size.

Darn, and I thought I was doing someone a good favour.

In any event, then, the RCA manual did initially say they were the same and
that is what I did recite up front.

I'd still believe that the 12Volt tube can produce a greater number of
electrons and thus would have better gain?

rtt


"unitron" wrote in message
om...
"Richard Tomkins" wrote in message
ws.com...
Ah, tubes, my past is back in vogue.

The obvious difference between the two is the heater voltages.

The RCA Tube Manual says they are the same but, the plate voltages are
different, 90 vs. 250, plate resistance , 6700 vs. 7700 ohms,
transconductance 300 vs. 2600 umhos, grid voltage for a plate current of
10
uA 7 vs. 18 volts, these being some items for use as a Class A
amplifier.

The 12SN7 would appear to be a beefier tube in use in a Vertical
Deflection
Amplifier.

The 12SN7 probably has a higher capability to generate electrons at the
cathode than the 6SN7, so it can probably produce more voltage swing at
the
plate.

rtt

snip

You missed the fine print in that RCA book.
The differences you cited aren't between the 6 and the 12, they are
between the two independent triodes inside the glass envelope. RCA
refers to them as "Unit No. 1" and "Unit No. 2". It's right above the
"Direct Interelectrode Capacitances" line.
It is a little confusingly laid out, due to RCA's attempts to get as
much info into the book as possible while remaining at a manageable
size.

Richard Tomkins wrote:

Darn, and I thought I was doing someone a good favour.

In any event, then, the RCA manual did initially say they were the same and
that is what I did recite up front.

I'd still believe that the 12Volt tube can produce a greater number of
electrons and thus would have better gain?

I doubt it. They probably have the same heaters in the two halves -- in
series in the 12V version and parallel in the 6V version.


rtt


"unitron" wrote in message
om...

"Richard Tomkins" wrote in message

ws.com...

Ah, tubes, my past is back in vogue.

The obvious difference between the two is the heater voltages.

The RCA Tube Manual says they are the same but, the plate voltages are
different, 90 vs. 250, plate resistance , 6700 vs. 7700 ohms,
transconductance 300 vs. 2600 umhos, grid voltage for a plate current of

10

uA 7 vs. 18 volts, these being some items for use as a Class A

amplifier.

The 12SN7 would appear to be a beefier tube in use in a Vertical

Deflection

Amplifier.

The 12SN7 probably has a higher capability to generate electrons at the
cathode than the 6SN7, so it can probably produce more voltage swing at

the

plate.

rtt

snip

You missed the fine print in that RCA book.
The differences you cited aren't between the 6 and the 12, they are
between the two independent triodes inside the glass envelope. RCA
refers to them as "Unit No. 1" and "Unit No. 2". It's right above the
"Direct Interelectrode Capacitances" line.
It is a little confusingly laid out, due to RCA's attempts to get as
much info into the book as possible while remaining at a manageable
size.





--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

Richard Tomkins wrote:

Darn, and I thought I was doing someone a good favour.

In any event, then, the RCA manual did initially say they were the same and
that is what I did recite up front.

I'd still believe that the 12Volt tube can produce a greater number of
electrons and thus would have better gain?

I doubt it. They probably have the same heaters in the two halves -- in
series in the 12V version and parallel in the 6V version.


rtt


"unitron" wrote in message
om...

"Richard Tomkins" wrote in message

ws.com...

Ah, tubes, my past is back in vogue.

The obvious difference between the two is the heater voltages.

The RCA Tube Manual says they are the same but, the plate voltages are
different, 90 vs. 250, plate resistance , 6700 vs. 7700 ohms,
transconductance 300 vs. 2600 umhos, grid voltage for a plate current of

10

uA 7 vs. 18 volts, these being some items for use as a Class A

amplifier.

The 12SN7 would appear to be a beefier tube in use in a Vertical

Deflection

Amplifier.

The 12SN7 probably has a higher capability to generate electrons at the
cathode than the 6SN7, so it can probably produce more voltage swing at

the

plate.

rtt

snip

You missed the fine print in that RCA book.
The differences you cited aren't between the 6 and the 12, they are
between the two independent triodes inside the glass envelope. RCA
refers to them as "Unit No. 1" and "Unit No. 2". It's right above the
"Direct Interelectrode Capacitances" line.
It is a little confusingly laid out, due to RCA's attempts to get as
much info into the book as possible while remaining at a manageable
size.





--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

Richard Tomkins wrote:

Darn, and I thought I was doing someone a good favour.

In any event, then, the RCA manual did initially say they were the same and
that is what I did recite up front.

I'd still believe that the 12Volt tube can produce a greater number of
electrons and thus would have better gain?

I doubt it. They probably have the same heaters in the two halves -- in
series in the 12V version and parallel in the 6V version.


rtt


"unitron" wrote in message
om...

"Richard Tomkins" wrote in message

ws.com...

Ah, tubes, my past is back in vogue.

The obvious difference between the two is the heater voltages.

The RCA Tube Manual says they are the same but, the plate voltages are
different, 90 vs. 250, plate resistance , 6700 vs. 7700 ohms,
transconductance 300 vs. 2600 umhos, grid voltage for a plate current of

10

uA 7 vs. 18 volts, these being some items for use as a Class A

amplifier.

The 12SN7 would appear to be a beefier tube in use in a Vertical

Deflection

Amplifier.

The 12SN7 probably has a higher capability to generate electrons at the
cathode than the 6SN7, so it can probably produce more voltage swing at

the

plate.

rtt

snip

You missed the fine print in that RCA book.
The differences you cited aren't between the 6 and the 12, they are
between the two independent triodes inside the glass envelope. RCA
refers to them as "Unit No. 1" and "Unit No. 2". It's right above the
"Direct Interelectrode Capacitances" line.
It is a little confusingly laid out, due to RCA's attempts to get as
much info into the book as possible while remaining at a manageable
size.





--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

In article , CJT
wrote:

Richard Tomkins wrote:

Darn, and I thought I was doing someone a good favour.

In any event, then, the RCA manual did initially say they were the same and
that is what I did recite up front.

I'd still believe that the 12Volt tube can produce a greater number of
electrons and thus would have better gain?

I doubt it. They probably have the same heaters in the two halves -- in
series in the 12V version and parallel in the 6V version.

It's easy to do the numbers; emission is a function of temperature, and
temperature is a function of heater *power*. Multiply heater volts times
heater amps; if they are the same, the tubes behave identically.

And, FWIW, the "number of electrons" has absolutely *nothing* to do with
the gain of the tube -- unless the number is zero. Then the gain is
likely to be zero too...

Some tubes were 6/12 volt. The filament had a center tap which was
brought out.You could hook 'em up either way.

Isaac

In article , CJT
wrote:

Richard Tomkins wrote:

Darn, and I thought I was doing someone a good favour.

In any event, then, the RCA manual did initially say they were the same and
that is what I did recite up front.

I'd still believe that the 12Volt tube can produce a greater number of
electrons and thus would have better gain?

I doubt it. They probably have the same heaters in the two halves -- in
series in the 12V version and parallel in the 6V version.

It's easy to do the numbers; emission is a function of temperature, and
temperature is a function of heater *power*. Multiply heater volts times
heater amps; if they are the same, the tubes behave identically.

And, FWIW, the "number of electrons" has absolutely *nothing* to do with
the gain of the tube -- unless the number is zero. Then the gain is
likely to be zero too...

Some tubes were 6/12 volt. The filament had a center tap which was
brought out.You could hook 'em up either way.

Isaac

In article , CJT
wrote:

Richard Tomkins wrote:

Darn, and I thought I was doing someone a good favour.

In any event, then, the RCA manual did initially say they were the same and
that is what I did recite up front.

I'd still believe that the 12Volt tube can produce a greater number of
electrons and thus would have better gain?

I doubt it. They probably have the same heaters in the two halves -- in
series in the 12V version and parallel in the 6V version.

It's easy to do the numbers; emission is a function of temperature, and
temperature is a function of heater *power*. Multiply heater volts times
heater amps; if they are the same, the tubes behave identically.

And, FWIW, the "number of electrons" has absolutely *nothing* to do with
the gain of the tube -- unless the number is zero. Then the gain is
likely to be zero too...

Some tubes were 6/12 volt. The filament had a center tap which was
brought out.You could hook 'em up either way.

Isaac

Isaac Wingfield wrote in message ...
In article , CJT
wrote:

Richard Tomkins wrote:

Darn, and I thought I was doing someone a good favour.

In any event, then, the RCA manual did initially say they were the same and
that is what I did recite up front.

I'd still believe that the 12Volt tube can produce a greater number of
electrons and thus would have better gain?

I doubt it. They probably have the same heaters in the two halves -- in
series in the 12V version and parallel in the 6V version.

It's easy to do the numbers; emission is a function of temperature, and
temperature is a function of heater *power*. Multiply heater volts times
heater amps; if they are the same, the tubes behave identically.

And, FWIW, the "number of electrons" has absolutely *nothing* to do with
the gain of the tube -- unless the number is zero. Then the gain is
likely to be zero too...

Some tubes were 6/12 volt. The filament had a center tap which was
brought out.You could hook 'em up either way.

Isaac


This one ain't center-tapped. Not enough pins available. The 12 gives
0.3 Amps of heater current at 12.6 volt and the 6 gives 0.6 Amps at
6.3 volts, so 37.8 Watts of heater power either way. The two
independant triodes aren't exactly identical (according to the specs)
but maximum plate dissipation for either is 5 Watts and with both
operating the max is 7.5 Watts total (so if one is running at 5 you
can't ask the other one for more than 2.5).

Isaac Wingfield wrote in message ...
In article , CJT
wrote:

Richard Tomkins wrote:

Darn, and I thought I was doing someone a good favour.

In any event, then, the RCA manual did initially say they were the same and
that is what I did recite up front.

I'd still believe that the 12Volt tube can produce a greater number of
electrons and thus would have better gain?

I doubt it. They probably have the same heaters in the two halves -- in
series in the 12V version and parallel in the 6V version.

It's easy to do the numbers; emission is a function of temperature, and
temperature is a function of heater *power*. Multiply heater volts times
heater amps; if they are the same, the tubes behave identically.

And, FWIW, the "number of electrons" has absolutely *nothing* to do with
the gain of the tube -- unless the number is zero. Then the gain is
likely to be zero too...

Some tubes were 6/12 volt. The filament had a center tap which was
brought out.You could hook 'em up either way.

Isaac


This one ain't center-tapped. Not enough pins available. The 12 gives
0.3 Amps of heater current at 12.6 volt and the 6 gives 0.6 Amps at
6.3 volts, so 37.8 Watts of heater power either way. The two
independant triodes aren't exactly identical (according to the specs)
but maximum plate dissipation for either is 5 Watts and with both
operating the max is 7.5 Watts total (so if one is running at 5 you
can't ask the other one for more than 2.5).

Isaac Wingfield wrote in message ...
In article , CJT
wrote:

Richard Tomkins wrote:

Darn, and I thought I was doing someone a good favour.

In any event, then, the RCA manual did initially say they were the same and
that is what I did recite up front.

I'd still believe that the 12Volt tube can produce a greater number of
electrons and thus would have better gain?

I doubt it. They probably have the same heaters in the two halves -- in
series in the 12V version and parallel in the 6V version.

It's easy to do the numbers; emission is a function of temperature, and
temperature is a function of heater *power*. Multiply heater volts times
heater amps; if they are the same, the tubes behave identically.

And, FWIW, the "number of electrons" has absolutely *nothing* to do with
the gain of the tube -- unless the number is zero. Then the gain is
likely to be zero too...

Some tubes were 6/12 volt. The filament had a center tap which was
brought out.You could hook 'em up either way.

Isaac


This one ain't center-tapped. Not enough pins available. The 12 gives
0.3 Amps of heater current at 12.6 volt and the 6 gives 0.6 Amps at
6.3 volts, so 37.8 Watts of heater power either way. The two
independant triodes aren't exactly identical (according to the specs)
but maximum plate dissipation for either is 5 Watts and with both
operating the max is 7.5 Watts total (so if one is running at 5 you
can't ask the other one for more than 2.5).