Firstly I apologise in advance if this has been covered already. I did look and I did find one similar thread but haven't seen any posts/answers that clear this up for me.
I am very curious about the Pass amps and would love to experience the F4 for myself. After reading up on the amp I see that flea watt tube amps can be used like a pre amp for the F4, a combination that is supposed to work well. I have Tubelab Simple SE. It is approx 6 - 8w depending on tubes. It has a volume pot but no rca line outputs, only speaker binding posts. The speakers that I use are Frugal horn MA 7.3.
Would my SSE be a suitable front end for F4.? If so how would i connect it to the F4? Would I need to connect an RCA line out to the output transformers output? I am using Hammond 1628sea as I am restricted to uk TX suppliers.
Any guidance would be appreciated.
Thanks
I am very curious about the Pass amps and would love to experience the F4 for myself. After reading up on the amp I see that flea watt tube amps can be used like a pre amp for the F4, a combination that is supposed to work well. I have Tubelab Simple SE. It is approx 6 - 8w depending on tubes. It has a volume pot but no rca line outputs, only speaker binding posts. The speakers that I use are Frugal horn MA 7.3.
Would my SSE be a suitable front end for F4.? If so how would i connect it to the F4? Would I need to connect an RCA line out to the output transformers output? I am using Hammond 1628sea as I am restricted to uk TX suppliers.
Any guidance would be appreciated.
Thanks
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Yes, would work very well, those who have driven F4 with a small valve SE amp seem to be absolutely smitten and happy with the combination. 
You’d need to make a cable with RCA on one end and wires on the other, and a 15 or 20 ohm 3W resistor. Connect the resistor across your SSE outputs and wire the RCA to it. Very simple.

You’d need to make a cable with RCA on one end and wires on the other, and a 15 or 20 ohm 3W resistor. Connect the resistor across your SSE outputs and wire the RCA to it. Very simple.
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Wow. Thanks for the quick reply. So have I understood correctly I could wire it to my speaker binding posts then (on the SSE). That is if I make up an arrangement for the resistors.
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Go for it, you will be super happy😀 And I can assure you, that F4 drives those Alpairs like nothing else.
Thanks for confirming that. I was worried about the sensitivity of the drivers as they are quoted at 86db that said I think I recall reading somewhere that Mark Fenlon says in reality they are more sensitive than 86db.
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Yes their sensitivity might look scary on paper, but in fact I'm able to drive them to their X-max with F4, enough gain and some bass heavy music.
I use F4 with Octal 6SN7 Aikido preamp into roughly 85-87db speakers and it works and sounds absolutely amazing.
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