Tube Rolling (6SN7, 12AU7/ECC82 & 6AS7/6080)

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Ok So I’m putting this here since I guess it applies to alot of different Amps, Pre-Amps, Power Amps, DACs, etc.

Kinda curious on other people’s takes on Driver Tubes, specifically 6SN7 and 12AU7/ECC82, plus any close enough equivalent, even things like using Dual tube Adapters like 6J5 + 6J5 to 6SN7. EDIT: Also Added 6AS7/6080 Since those are pretty common too, so a Power Tube section has been added for this list too.

I’m building my own amp based around the 6SN7 and the 12AU7 as Drivers (And as Shunt Regulators, although the tube used there doesn’t have to be such a high quality tube honestly), so kinda curious as to see if there are any recommendations.

Oh Also heater current of the driver is a non-issue in this case, so recommend things with higher heater current like the Mullard CV181

Also for anyone who owns a Darkvoice, Lyr, Crack, Crackatwoa, etc, this might help you explore new options. Stuff like 6CG7 to replace a 6SN7 or 6922, I just want opinions on the tubes you guys have used, maybe I can compile a list and put it here to help any tube newcomers that want to know what they can stick into their Amp safely.

EDIT: Added New Portion involving tubes based off of the 6AS7/6080, the more amount of tube data that can be documented for the ease of use of everyone else, the better.

I mean you can search up datasheets but It’ll help quite a bit if an extensive list was made for this kind of thing with all the tube types gathered in One Place (kinda like this one: https://www.head-fi.org/threads/for-6as7g-tube-rollers-here.410326/) but maybe a bit more towards electrical values since the amp circuit also plays heavily on how a tube will act/sound, although usually there are constant characteristics that a tube tends to retain regardless of a circuit.

Still for the actual discussion, reference sound and the amp used, but if possible (although not necessary, I can eventually Search It up if I have the tube Name) add electrical values (Heater Current, Plate Resistance/Current/Voltage, Gain, and Transconductance).

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DRIVER TUBES:

6SN7 (+ Equivalents):

  1. 6SN7/6SN7(GT) (Can Replace 12AU7):
    Heater Current: 0.6 Amp @ 6.3 VAC/VDC
    Plate Current: 10.0/9.0 mA
    Plate Voltage: 90-250 VDC, 300 VDC Max
    Plate Resistance: 6700/7700 Ohm
    Amplification Factor: 20.0
    Transconductance: .0030/.0026 Ohm

  2. 6SN7(GTA/GTB) (10-Sec Warm-Up):
    Heater Current: 0.6 Amp @ 6.3 VAC/VDC
    Plate Current: 10.0/9.0 mA
    Plate Voltage: 90-250 VDC, 450 VDC Max (Class A)
    Plate Resistance: 6700/7700 Ohm
    Amplification Factor: 20.0
    Transconductance: .0030/.0026 Ohm

  3. 6J5 (“Half” 6SN7, Single Triode, Metal Shell)
    Heater Current: 0.3 Amp @ 6.3 VAC/VDC
    Plate Current: 10.0/9.0 mA
    Plate Voltage: 90-250 VDC, 300 VDC Max
    Plate Resistance: 6700/7700 Ohm
    Amplification Factor: 20.0
    Transconductance: .0030/.0026 Ohm

  4. 6CG7 (9-Pin 6SN7, Internal Shield, 11-Sec W-Up)
    Heater Current: 0.6 Amp @ 6.3 VAC/VDC
    Plate Current: 10.0/9.0 mA
    Plate Voltage: 90-250 VDC, 300 VDC Max (Class A)
    Plate Resistance: 6700/7700 Ohm
    Amplification Factor: 20.0
    Transconductance: .0030/.0026 Ohm

  5. 6922/E88CC (9-Pin Similar, Internal Shield)
    Heater Current: 0.3 Amp @ 6.3 VAC/VDC
    Plate Current: 15.0/12.0 mA
    Plate Voltage: 90-250 VDC, 400 VDC (@ 0 mA)
    Plate Resistance: 3000 Ohm
    Amplification Factor: 33.0
    Transconductance: .00125/.00115 Ohm

  6. 76/VT-76 (5-Pin UX5 Socket SUPER TRIODE!)
    Heater Current: 0.3 Amp @ 6.3 VAC/VDC
    Plate Current: 2.5/5.0 mA
    Plate Voltage: 100-250 VDC
    Plate Resistance: 12000/9500
    Amplification Factor: 13.8
    Transconductance: .00115/.00145 Ohm (Work in Progress)

  7. 7193/CV6/2C22 (Development 6J5)
    Heater Current: 0.3 Amp @ 6.3 VAC/VDC
    Plate Current: 2.5/5.0 mA
    Plate Voltage: 90-250 VDC, 300 VDC Max
    Plate Resistance: 6600
    Amplification Factor: 20.0
    Transconductance: .00300 Ohm

  8. CV181/ECC32 (“1 Amp” Heater, Mullard)
    Heater Current: 0.95 Amp @ 6.3 VAC/VDC
    Plate Current: 6.0 mA
    Plate Voltage: 90-250 VDC, 300 VDC Max
    Plate Resistance: 14000
    Amplification Factor: 32.0
    Transconductance: 2.3 mA/V (Value in Ohm N.A.)

  9. CV181-Z/TII (6SN7 Equivalent, ST Bottle)
    Heater Current: 0.6 Amp @ 6.3 VAC/VDC
    Plate Current: 10.0/9.0 mA
    Plate Voltage: 90-250 VDC
    Plate Resistance: 6700/7700 Ohm
    Amplification Factor: 20.0
    Transconductance: .0030/.0026 Ohm

  10. 6F8G (Equivalent to Dual 6J5, Grid Cap) *
    Heater Current: 0.6 Amp @ 6.3 VAC/VDC
    Plate Current: 10.0/9.0 mA
    Plate Voltage: 90-250 VDC, 300 VDC Max
    Plate Resistance: 6700/7700 Ohm
    Amplification Factor: 20.0
    Transconductance: .0030/.0026 Ohm

12AU7 (+ Equivalents):

  1. 12AU7 (Standard Tube, Can Replace 6SN7)
    Heater Current: 0.3/0.15 Amp @ 6.3/12.6 VAC/VDC
    Plate Current: 11.8/10.5 mA, 20.0 mA Max
    Plate Voltage: 90-250 VDC, 300 VDC Max
    Plate Resistance: 6500/7700 Ohm
    Amplification Factor: ~ 17.0
    Transconductance: .0031/.0022 Ohm

  2. 12AU7-A/WA (Low Microphonics)
    Heater Current: 0.3/0.15 Amp @ 6.3/12.6 VAC/VDC
    Plate Current: 11.8/10.5 mA, 20.0 mA Max
    Plate Voltage: 90-250 VDC, 300 VDC Max
    Plate Resistance: 6225/7700 Ohm
    Amplification Factor: ~ 17.0
    Transconductance: .0031/.0022 Ohm

  3. 5814 (Higher Heater Current)
    Heater Current: 0.35/0.175 A @ 6.3/12.6 VAC/VDC
    Plate Current: 11.8/10.5 mA, 20.0 mA Max
    Plate Voltage: 90-250 VDC, 330 VDC Max
    Plate Resistance: 6225/7700 Ohm
    Amplification Factor: ~ 17.0
    Transconductance: .0031/.0022 Ohm

  4. 5814-A (Higher Heater Current/Plate Current)
    Heater Current: 0.35/0.175 A @ 6.3/12.6 VAC/VDC
    Plate Current: 12.3/10.5 mA, 20.0 mA Max
    Plate Voltage: 90-250 VDC, 330 VDC Max
    Plate Resistance: 6225/7700 Ohm
    Amplification Factor: ~ 17.0
    Transconductance: .0031/.0022 Ohm

  5. CV491 (Advanced/Military 12AU7)
    Heater Current: 0.3/0.15 A @ 6.3/12.6 VAC/VDC
    Plate Current: 12.3/10.5 mA, 20.0 mA Max
    Plate Voltage: 90-250 VDC, 330 VDC Max
    Plate Resistance: 6225/7700 Ohm
    Amplification Factor: ~ 17.0
    Transconductance: .0031/.0022 Ohm

POWER TUBES:

6AS7/6080 (+ Equivalents):

  1. 6AS7/6AS7(G) (Common, High Variety)
    Heater Current: 2.5 Amp @ 6.3 VAC/VDC
    Plate Current: 110-125 mA
    Plate Voltage: 135-250 VDC, 300 VDC Max
    Plate Resistance: 280 Ohm
    Amplification Factor: 2.0
    Transconductance: .0070 Ohm

  2. 6AS7(GA) (Straight Bottle 6AS7(G))
    Heater Current: 2.5 Amp @ 6.3 VAC/VDC
    Plate Current: 110-125 mA
    Plate Voltage: 135-250 VDC, 300 VDC Max
    Plate Resistance: 280 Ohm
    Amplification Factor: 2.0
    Transconductance: .0070 Ohm

  3. 6080 (Common, High Variety)
    Heater Current: 2.5 Amp @ 6.3 VAC/VDC
    Plate Current: 110-125 mA
    Plate Voltage: 135-250 VDC, 300 VDC Max
    Plate Resistance: 280 Ohm
    Amplification Factor: 2
    Transconductance: .0070 Ohm

  4. 5998(A) (Tung-Sol Specs, Low Output Z) **
    Heater Current: 2.4 Amp @ 6.3 VAC/VDC
    Plate Current: 50-125 mA, 140 mA MAX
    Plate Voltage: 110-250 VDC, 275 VDC Max
    Plate Resistance: 350 Ohm
    Amplification Factor: 5.4
    Transconductance: ~.0155 Ohm

  5. 5998 (Tung-Sol Specs, Low Output Z) **
    Heater Current: 2.4 Amp @ 6.3 VAC/VDC
    Plate Current: 50-125 mA, 140 mA MAX
    Plate Voltage: 135-250 VDC, 275 VDC Max
    Plate Resistance: 280 Ohm
    Amplification Factor: 5.5
    Transconductance: ~.0140 Ohm

  6. 421A (WE, Super Low Output Z, Rare + $$$)
    Heater Current: 2.4 Amp @ 6.3 VAC/VDC
    Plate Current: 100-125 mA
    Plate Voltage: 110-250 VDC
    Plate Resistance: 330/305 Ohm
    Amplification Factor: 5.9/6.3
    Transconductance: .0180/.0200 Ohm

  7. 6528/6528(A) (Ultra Low Output Z, 5.0 A Heater)
    Heater Current: 5.0 Amp @ 6.3 VAC/VDC
    Plate Current: 100-125 mA, 300 mA Max
    Plate Voltage: 110-250 VDC, 400 VDC Max (@ 0 mA)
    Plate Resistance: 245 Ohm
    Amplification Factor: 9.0
    Transconductance: .0370 Ohm

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(Note: *Transconductance: Higher Plate Current = Higher Transconductance = Lower Output Impedance, Especially as Cathode Follower. Dynamic Value)

*(Note: Interesting Concept for the 6F8G, Can Be used as a Single Triode (6J5) and have Signal enter the Grid Cap Triode for Better Signal Stability/Isolation, Other Triode Half can be used as a Shunt Regulator or for some other purpose, maybe using half of 4 for Balanced via Grid Cap and the other half of 4 as Phase Splitters?)

**(Note: 5998 v. 5998(A) is essentially comprised of relatively minor value changes, most of which are Dynamic and may fluctuate, so don’t worry too much as to which one you buy an what manufacturer to look for if sound is what you’re looking for, since that is subjective and not geared towards a certain performance (Lowering Output Impedance for Example).

For performance, based on the specs of both, different sites refer to the transconductance being significantly lower on the 5998(A) compared to the 5998, I only present what I found in the Data Sheets:

5998 “Tung-Sol”:http://www.tubebooks.org/tubedata/5998_TS.PDF

&

5998(A) “Tung-Sol”: https://frank.pocnet.net/sheets/127/5/5998A.pdf

Since I wanted to reference the spec sheets for these tubes in particular to the same manufacturer as to show that Transconductance, at least for “Tung-Sol” manufactured 5998 and 5998(A) tubes are in relative proximity to each other.)

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