TO BUY ECC32 MULLARD
TO BUY ECC33 MULLARD

ECC32=CV181 Mullard 1950's (TOP OF PAGE) ECC33=6SN7GT Mullard 1950's - 1960's (BOTTOM OF PAGE)
ECC32=CV181 Mullard 1950's (Very well-balanced tube from top to bottom. Great mid-detail and very romantic sound with ZERO harshness, not grainy. It also has very good bass resolution, but bass is not exteremly deep due to higher plate resistance) - Woo Audio WA6 modded - Apex Peak single tube hybrid headphone amp/preamp - Liquid Glass headphone amp by Cavalli Audio - Audio Aero Capitole - TransTRAC amp - France - Dehavilland Ultraverve linestage - Singlepower headphone amp - Cary preamps and amps - Cary SLI-80 - SET amps - Modwright Transporter - Woo Audio WA5 - Woo Audio WA6 modded - Eddie Current TO BUY ECC32 MULLARD

ELECTRICAL COMPARISON BETWEEN 6SN7GTB / ECC32 / ECC33 / ECC34 (ECC32 has higher plate resistance than 6SN7GTB) (ECC33 has higher Mu=amplification factor and Gm than ECC32) (ECC34 has low plate resistance and work best at lower plate voltages) (ECC34: Vplate=140V, Vgrid=-6, Ip=10ma, Gm=3700, Mu=16.7, Rp=4.6Kohms, Pa=1.4W)
  6SN7GTB ECC32 ECC33 ECC34
vplate: 200V 250V 200V 250V 200V 250V 200V 250V
Vgrid
-5
-8
-3
-4.6
-3
-4.6
-12
-15
Ip (ma)
8.6
7.1
5
6
8
7.5
7.8
10
Mu
41
38
51
32
68
37.5
24.6
15.6
Gm (trans)
5700
5000
3500
2300
7700
4000
4500
3100
Rp (ohm)
7.3
8.2
14.5
14
8.9
9.3
5.5
5.1
Pa (W)
1.7
1.8
1
1.5
1.6
1.8
1.56
2.5



ECC32=CV181 Mullard Specifications (not an exact 6SN7GT substitute) (6.3V @ 950ma Filament, Maximum ratings: Vplate=300V, Iplate=50ma, Vfil-cathode=50V, Pwatts=5) (Typical operation: Vplate=250V, Vgrid = -4.6V, Iplate=6ma, Gm=2300, Mu=32, Rplate=14Kohms, Rk=750 ohms) (the ECC32 is the best overall sounding 6SN7GT replacement; the ECC32=CV181 is NOT an exact electrical equivalent to a 6SN7GTB and should not be substituted for a 6SN7GTB if the plate voltage is over 300VDC and it may not work well in some applications where the negative grid bias is too high. Also, the ECC32 requires 950ma on the filament verus 600ma for a 6SN7GTB, but this tube has a glorious rich midrange, smooth and open top end, with very good bass articulation, music sounds real with this tube) 6SN7GTB vs ECC32=CV181 Circuit Application Comparison: ----------------------------------------------------- (results of 2 sample 6SN7GTB Sylvania and ECC32=CV181 Mullard tested on SOFIA curve tracer): 6SN7GTB: Vplate = 200V, Vgrid = -2V, Iplate = 12ma, Gm = 5.4, Rp = 7.7Kohms, Mu = 41 Vplate = 250V, Vgrid = -8V, Iplate = 9ma, Gm = 4.2, Rp = 9.1Kohms, Mu = 38 (typical) Vplate = 300V, Vgrid = -12V, Iplate = 5ma, Gm = 3, Rp = 11.9Kohms, Mu = 30 Vplate = 450V, Vgrid = -20V, Iplate = 3ma (tube data manual lists the 6SN7GTB with a Mu=20 @ 250Vplate, -8Vgrid) ECC32=CV181: Vplate = 200V, Vgrid = -2V, Iplate = 8ma, Gm = 4.2, Rp = 12.8Kohms, Mu = 54 Vplate = 250V, Vgrid = -4.5V, Iplate = 6ma, Gm = 3.8, Rp = 15.4Kohms, Mu = 52 (typical) Vplate = 300V, Vgrid = -6V, Iplate = 5.8ma, Gm = 3.5, Rp = 16Kohms Vplate = 350V, Vgrid = -8V, Iplate = 4ma, Gm = 3, Rp = 16.9Kohms, Mu= 51 * 6SN7GT has higher transconductance (Gm), lower (Mu) and lower plate resistance (Rp) than a ECC32=CV181 Customer Comments on ECC32 misbranded as ECC33: ---------------------------------------------- "The ECC32 misbranded as ECC33 (listed below) are amazingly accurate. Matched quad of these plus the Sylvania 6SN7WGT metal base was absolutely incredible. The music was dead-center with dead-accurate focus and stability. It seemed like music was so smoothly eminating from a high-energy nuclear core that remained highly focused and centered. BUT, these ECC32 are not in the same league as the ECC32 Ultra-Low Noise Cryo-Valve's -- the bass was softer, there was less bloom & "high-energy" presence and could not match the ECC32's in overall immediacy and weight. But still extremely accurate.....ma ma mia SOPHIA!" * ECC32 sound best with orchestral, chamber music, jazz and blues * most brown base ECC32 have "D" getter halos * most black base ECC32 have upside-down "tray" shaped or "L" bracket getter halos


ECC33=CV2821=6SN7GT Mullard 1956-1963 (6.3V @ 400ma Filament, Maximum ratings: Vplate=300V, Iplate=20ma, Vfil-cathode=100V, Pwatts=2.5) (Typical operation: Vplate=250V, Vgrid = -4V, Iplate=9ma, Gm=3600, Mu=35, Rplate=9.7Kohms, Rk=450 ohms) "Sonic Comments: the ECC33s sound great - big, expansive and very clean and open, but a bit shy of bass" - Bada PH-12 headphone amp - Eddie Current Balancing Act ECC33 CHARACTERISTICS from Mullard tube data book: Vplate=250V, Vgrid=-4V, Iplate=9ma, Mu=35, Gm=3600, Rplate= 9.7Kohms ECC33 Mullard BLACK BASE: ------------------------ TO BUY ECC33 Mullard

ECC33=CV2821=6SN7GT Mullard (REFERENCE PICTURES) ECC33 Mullard NOS brown base and black base 1958-1963 Click here to see ECC33 Mullard black base 1963 branded Philips Miniwatt Click here to see ECC33 Mullard black base 1950's (far left) Click here to see ECC33 Mullard branded Valvo England 1958 Click here to see (16) ECC33 Mullard branded Valvo England boxed Click here to see ECC33 Mullard black base 1950's (reference picture) Click here to see ECC33 Mullard black base 1961 (reference picture)