Your choice will be limited if you want bass and treble control. They are currently out of fashion within DIY community. Reason: this feature typically cause more audio degradation then help.
If you must have treble and base control. You might have to build two kits, a pre-amp and a power amp.
If you must have treble and base control. You might have to build two kits, a pre-amp and a power amp.
I have built a few Single end tube amplifiers { EL34/6H9C, 6N3C/12AT7} and all without Bass and Treble controls they only artificially boost and untrue sound if you have a great matching speaker system with the right xovers in them the sound I have found to be excellent. Plenty of low end and high end when need. Just my opinion.
I have truly little to add as I can't see myself buying a preamp kit. That being said, if you google, there are at least a few tube preamp kits out there with tone controls.
If by kit you mean more generally DIY, then I had a look, and frankly there do not seem to be any published designs that do not have something that I don't like about them, and prevents me from recommending them.
You can consider building one of the published designs that use a 12AU7, and substituting a 6SN7 (you need to adjust bias though). I believe both have plate resistances of about 7K and so the tone stack should work as designed.
If by kit you mean more generally DIY, then I had a look, and frankly there do not seem to be any published designs that do not have something that I don't like about them, and prevents me from recommending them.
You can consider building one of the published designs that use a 12AU7, and substituting a 6SN7 (you need to adjust bias though). I believe both have plate resistances of about 7K and so the tone stack should work as designed.
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No affiliation or experience with this kit, but here's one: the SP9.
Vacuum Tube Audio preamp kits
This is one of the very few I'm aware of that are available in kit form with tone controls. A few more choices exist if you can live w/o tone controls.
Vacuum Tube Audio preamp kits
This is one of the very few I'm aware of that are available in kit form with tone controls. A few more choices exist if you can live w/o tone controls.
Pete Millett's schematic shows a sensible 100 Kohm I/P impedance. Commercial CDPs and (IMO) well executed phono preamps can drive the IHF "standard" 10 Kohm load. A simple 10 Kohm passive control center should serve the OP well. Just keep the cabling between control center and amp short/low capacitance. Low capacitance is unshielded and braided.
JMO, a box, source switching, an attenuator of some kind, and some RCA females does not require a kit. FWIW, my preference for the attenuator is a PEC of Canada made KKA series hot molded carbon pot. purchased from DigiKey.
JMO, a box, source switching, an attenuator of some kind, and some RCA females does not require a kit. FWIW, my preference for the attenuator is a PEC of Canada made KKA series hot molded carbon pot. purchased from DigiKey.
Well, if you are really willing to not have tone controls, you have to look at why you really want a preamp in this case where your power amp doesn't need it. Driving a long interconnect? Switching multiple sources? Looks cool? Being honest is the road to happiness.
None of the kits excite me personally. I think SY's design are great, and would consider one of those. I think you can maybe find some PCB's being sold for them.
There was a member here a while back who put a cheap remote system inside his preamp, one of those remote control + channel switching for some ridiculously low price from China things. The purists were horrified, but it looked fantastic.
None of the kits excite me personally. I think SY's design are great, and would consider one of those. I think you can maybe find some PCB's being sold for them.
There was a member here a while back who put a cheap remote system inside his preamp, one of those remote control + channel switching for some ridiculously low price from China things. The purists were horrified, but it looked fantastic.
Expensive little dudes.
Tell me more about the benefits of hot molded carbon? I'm guessing that gives a smoother tapered surface that makes them more accurate?
Carbon is "warmer" than the metal film parts found in stepped attenuators. The PEC parts are less expensive than stepped attenuators and they are rugged milspec. For instance, the wipers are spring loaded machined blocks of carbon, not metal that cuts into the resistance element.
If the O/P builds with Mr. Millett's PCB, a separate control center may be desirable. Whether the center is passive or active will depend on the specific listening room setup. For the most part, I agree that little or no line stage gain is appropriate.
More than 1 phono preamp offering currently available is unable to drive the IFH "standard" 10 Kohm load. Should such a setup be chosen, active circuitry of some kind will be needed in the line stage.
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