Hi.
I'm looking to build a valve pre amp to go with my bridged amp camp amps.
I'd heard the Bottlehead Quickie was a nice match but it's also discontinued and my skills for a scratch build are non existent.
I can build stuff given instructions but that's it.
So can anyone reccomended a kit?
Or is there a parts list and instructions for the Quickie that I've missed. Can't see anything after a Google search.
All suggestions appreciated.
Rik
I'm looking to build a valve pre amp to go with my bridged amp camp amps.
I'd heard the Bottlehead Quickie was a nice match but it's also discontinued and my skills for a scratch build are non existent.
I can build stuff given instructions but that's it.
So can anyone reccomended a kit?
Or is there a parts list and instructions for the Quickie that I've missed. Can't see anything after a Google search.
All suggestions appreciated.
Rik
Not a kit but my recent preamp build, the Flow, is as simple as it gets. It could even be built with a screwdriver like a couple of my recent amp projects. Cost was just under $100. It’s a simpler circuit than the amp my then 10-year-old granddaughter built last summer.
https://audiokarma.org/forums/index.php?threads/the-flow-pre4d-a-diy-tube-preamp.1084409/
I just posted this updated schematic:
It's slightly over my budget which I should have said is about 200 quid.
I'll definitely keep it in mind though and may be able to stretch if I don't find anything else.
For that budget I would look to one of the Chinese-made kits offered on AliExpress. Yes it's shipped from around the globe but at least you're not subject to the tariffs. They offer many different kits so you'll have to pick one that's gonna do what you need. They are wired point-to-point, so you'll have to read a circuit diagram. But then you can wire it however you want. Since you're driving solid-state amps you might want to look at something designed for that.
Build the Nelson Pass B1 Buffer. Matches the camp amp in terms of output impedance/input impedance. Easy to build.
Now this sounds like the answer. Unfortunately it looks like it's sold out 😭
Enclosure
Transformer
Rectifier(s)
Power supply caps
Coupling caps
Bypass caps
Vol Pot
Input selector switch
RCA jacks
IEC jack + fuse holder
Power switch
Hook-up wire
Shielded cable
Assembly hardware
Grounding lugs
I just can't see how that breaks €200.
w
Transformer
Rectifier(s)
Power supply caps
Coupling caps
Bypass caps
Vol Pot
Input selector switch
RCA jacks
IEC jack + fuse holder
Power switch
Hook-up wire
Shielded cable
Assembly hardware
Grounding lugs
I just can't see how that breaks €200.
w
Take a look at E-bay. There are pcb-s, and you must find som resistors, capacitors, and j-fets. Sounds great and it is not rocket-science. Easy to build!
The build I posted above cost just under $100. I use sources that have variable outputs (DACs, streamers) so it would cost a bit more if you have a source with a fixed output and need to add a volume control.
It’s designed specifically to work with SS and Class D amps that have low input impedance. Because the tube has a low plate resistance it has an output impedance that’s under 1k so no cathode follower is needed.
Mu is ~7 or 8. Of course, most amps can be driven to full power with less than a line level signal and don’t need any gain at all. The Russian tubes cost $3 each. American or European 6CW5 / EL86 are only a bit more.
It’s so simple that, even if you can’t read a schematic, you could probably build it from the pic:
Cracking! Some good stuff to think about there.
Appreciate your input folks.
I'll let you know what I decide.
Rik
Appreciate your input folks.
I'll let you know what I decide.
Rik