Tubes Asylum

Posted by cin5 (A) on July 21, 2024 at 17:47:36

But please help me find my way out of this conundrum:

I want to drive a ~ 90db SPL/w/m center channel speaker either of four ways:

1.) A ~ 10 watt mono tube amp. Budget ~ $2.7K

From the DAC output feeding a LOW power tube amp. Driving the center speaker even with any of these lesser 300B SET mono blocks?

https://www.google.com/search?q=300b+mono+set+amplifier+between+$1,000+and+$3,500&udm=28&shoprs=CAESFhIUCQAAAABlzc1BEQAAAGC4E-pBGAEYBSoXMzAwYiBtb25vIHNldCBhbXBsaWZpZXIyMQgFEg8kMSwwMDAgLSAkMyw1MDAYAiIWEhQJAAAAAGXNzUERAAAAYLgT6kEYASoCGAFYprMgYAI&sa=X&ved=2ahUKEwj569e1l7mHAxVpEVkFHSYsCDkQ268JKAJ6BAgQEB8&biw=1066&bih=438&dpr=1.2

2.) The other idea was a 45 tube amp, which I've heard can rival the sound of 300B SETs, but I can't find any around. Any suggested 45 mono amp under $2.5K? But do they run much hotter and/or have higher power draw than a cheap 300B mono block?

3.) My stock First Watt F4 amp in balanced mono mode. https://www.firstwatt.com/product/f4/
https://www.firstwatt.com/wp-content/uploads/2023/08/prod_f4_man.pdf

As the F4 as a mono block does 100 watts, my room's only ~ 2800 cu ft and I'd be only 13 ft away how much input signal voltage could the F4 really need, even to sound it's best under these conditions?

That's why I wanted to know if someone has ever put a balanced passive line stage between the F4 and a balanced output source-like a multichannel DAC, which will have a ~ 4.6V output.
https://static1.squarespace.com/static/5e15d4fba20f9d0f914ce7aa/t/5ecbdb96fd31365e4fd5daf5/1590418329103/convert-8-chop-shop.pdf

or this DAC card for the Merging Hapi DAC offering much higher output voltage?
https://www.bhphotovideo.com/c/product/1806156-REG/merging_technologies_700341_da8_output_card_up.html

Would there any loss in sound quality using a passive line stage like these, assuming their balanced stereo passive outputs could be bridged to feed the F4 in balanced mono mode? https://khozmo.com/product-category/preamplifiers/

4.) However, as many F4 users have said, as it's quite the chameleon and will essentially sound much like whatever's feeding it. Thus, the F4 in balanced mono mode fed from a fully balanced tube line stage?

Budget ~ $2500. I would think this last option might be best as I would just need the best sounding tube line stage I can afford. But which for awesome sound stage size, spot on imaging, holographic mids and airy highs?

Going kind of nuts with this. Please share ideas.

Edits: 07/21/24   07/21/24