Tube output

Primary impedance Secondary impedance Max power capability at 30 Hz, Push-Pull Max power capability at 30 Hz, Single EndWeightTransformer type Configuration
6004 Ω700W140W4.5 kgLL1693
6504 Ω250W50W2.5 kgLL1627C
6804 Ω700W140W4.6 kgLL2768C
6808 Ω700W140W4.6 kgLL2768D
68016 Ω700W140W4.6 kgLL2768E
1k4 Ω360W70W4.5 kgLL1693B
1.2k4 Ω125W25W2.5 kgLL1627B
1.2k4 Ω180W36W2.5 kgLL2752C
1.2k4 Ω360W70W4.6 kgLL2768B
1.2k8 Ω125W25W2.5 kgLL1627C
1.2k8 Ω180W36W2.5 kgLL2752D
1.2k8 Ω360W70W4.6 kgLL2768C
1.2k16 Ω125W25W2.5 kgLL1627D
1.2k16 Ω360W70W4.6 kgLL2768D
1.6k4 Ω250W50W2.5 kgLL1623C
1.6k8 Ω250W50W2.5 kgLL1623D
1.6k16 Ω250W50W2.5 kgLL1623E
2k4 Ω105W21W2.5 kgLL2752B
2k 8 Ω105W21W2.5 kgLL2752C
2k16 Ω105W21W2.5 kgLL2752D
2.3k8 Ω62W13W2.5 kgLL1627B
2.3k8 Ω180W35W4.5 kgLL1693
2.3k16 Ω62W13W2.5 kgLL1627C
2.3k16 Ω180W35W4.5 kgLL1693
2.6k4 Ω188W36W2.5 kgLL1679C
2.6k8 Ω188W36W2.5 kgLL1679D
2.6k16 Ω188W36W2.5 kgLL1679E
2.7k8 Ω180W35W4.6 kgLL2768B
2.7k16 Ω180W35W4.6 kgLL2768C
3k4 Ω125W25W2.5 kgLL1623B
3k8 Ω12W2.2W0.75 kgLL2766B
3k8 Ω55W10W1.4 kgLL1664-
3k8 Ω125W25W2.5 kgLL1623C
3k16 Ω12W2.2W0.75 kgLL2766C
3.1k5 Ω105W21W2.5 kgLL2770
3.1k : 5
3.2k8 Ω100W20W2.5 kgLL27703.1k : 8
3k16 Ω125W25W2.5 kgLL1623D
3.3k4 Ω250W50W2.5 kgLL1620C
3.3k8 Ω250W50W2.5 kgLL1620D
3.3k16 Ω250W50W2.5 kgLL1620E
4 Ω105W20W2.5 kgLL1679B
4.5k8 Ω105W20W2.5 kgLL1679C
4.5k16 Ω105W20W2.5 kgLL1679D
4.6k8 Ω45W10W2.5 kgLL2752B
4.6k 16 Ω45W10W2.5 kgLL2752C
4.7k5 Ω100W20W2.5 kgLL27695 Ω
4.7k 5 and 8 Ω100W20W2.5 kgLL27695+8 (Elekit)
4.7k8 Ω100W20W2.5 kgLL27698 Ω
5k8 Ω40W8W1.4 kgLL1663-
5.5k4 Ω320W60W4.0 kg
5.5k5 Ω40W8W1.4 kgLL1682-
5.5k8 Ω320W60W4.0 kgLL1688D
5.5k16 Ω320W60W4.0 kgLL1688E
5.6k8 Ω62W13W2.5 kgLL1623B
5.6k16 Ω62W13W2.5 kgLL1623C
6k4 Ω24W4W0.75 kgLL2766B
6k4 Ω125W25W2.5 kgLL1620B
6k8 Ω24W4W0.75 kgLL2766C
6k8 Ω125W25W2.5 kgLL1620C
6k16 Ω24W4W0.75 kgLL2766D
6k16 Ω125W25W2.5 kgLL1620D
6.5k4 Ω350W50W2.5 kgLL9202C
6.5k8 Ω250W50W2.5 kgLL9202D
6.5k16 Ω250W50W2.5 kgLL9202E
9k8 Ω160W30W4.6 kgLL1691-
9.2k 4 Ω160W30W4.0 kgLL1688B
9.2k8 Ω160W30W4.0 kgLL1688C
9.2k16 Ω160W30W4.0 kgLL1688D
9.7k8 Ω45W9W2.5 kgLL1679B
9.7k16 Ω45W9W2.5 kgLL1679C
10k4 Ω160W30W4.6 kgLL1691D-
10k 16 Ω160W30W4.6 kgLL1691D-
11k4 Ω125W25W2.5 kgLL9202B
11k 8 Ω95W18W4.6 kgLL2755-
11k8 Ω125W25W2.5 kgLL9202C
11k16 Ω125W25W2.5 kgLL9202D
11.5k8 Ω62W13W2.5 kgLL1620B
11.5k16 Ω62W13W2.5 kgLL1620C
16k4 Ω-5W1.4 kgLL2735F -
16k8 Ω-5W1.4 kgLL2735B -
16k16 Ω-5W1.4 kgLL2735F-
20k4 Ω160W30W4.6 kgLL1691E-
20k8 Ω160W30W4.6 kgLL1691B-
20k16 Ω160W30W4.6 kgLL1691E-
23k8 Ω62W13W2.5 kgLL9202B
23k16 Ω62W13W2.5 kgLL9202C

  • If you need to more easily switch between different speaker impedances on our output transformers LL1620, LL1623 and LL1627, this sheet suggests two different wiring alternatives where the OPT secondary is reconnected using only three jumpers.
  • The LL1620CFB_8 and LL1620CFB_25 are special version of the LL1620 where the primary windings have been split to allow for (8% and 25%) cathode feedback connections.
  • The 2.5kg and the 1.4 kg transformers above are available with amorphous iron C-cores. We expect all application parameters to be similar for the amorphous core and the silicon iron cores, except that the amorphous cores signal handling capability is slightly smaller.

From a purely engineering point of view, we cannot justify the fairly high price of our amorphous core OPTs. But we have actually received a lot of praise for their sound quality, such as this report.

When considering testing an amorphous core transformer, please note that they are said to require much longer break in time than what is normally required for silicon-iron cores.