• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Pot for project test

I' m building a Tubes 4 HiFi, SP-14, 6SN7 preamp. I purchased only the bare board and sourced all the components. I'm nearing the point where I will be able to test the assembly and compare some alternatives - like coax vs twisted pair, I have several tube sets availabe to try, and some outout cap alternatives that I can roll from other projects.

Anyway, I've got around $400 into it right now and I want ro see how good it is before investing more money into it. If it cannot, at this stage, out shine my Mac C-27, then now might be a good time to cut my losses.

One component worries me though. For testing, I purchased a 100k, Alps RF 2702 from Asia for $9.95 delivered. I would spend serious money on a good attenuator if the preamp warranted the investment. But I'm concerned that the little Alps pot might screw up to the test. (I even read somewhere thst the RH 2702 was a Chinese knock-off.)

Any thoughts on the Alps and possibly a better alternative for my purposes?

Thanks
 
The preamp has passed all listening tests and is about to be moved from a cake pan to a legitimate long term chassis.

I took rayma's suggestion and used the Glassware A3 in the test phases. It performed beautifully for test purposes. However, it has a few flaws and its unique design makes it cumbersome to install and to use; so it's going to be replaced.

I'm not interested in a traditional pot, rather a stepped/ladder type. There are several possibilities like: Single control like Khozmo 48 and 64 stepped; Shallco/Elma 24/48/64 twin mono; and some three knob systems like the Glassware. I think attenuation is important to sound quality. Most of these components have unique chassis mounting requirements, and they're not cheap. So whatever I end up buying will have to be permanent.

Any suggestions would be welcome.
 
The preamp has passed all listening tests and is about to be moved from a cake pan to a legitimate long term chassis.

I took rayma's suggestion and used the Glassware A3 in the test phases. It performed beautifully for test purposes. However, it has a few flaws and its unique design makes it cumbersome to install and to use; so it's going to be replaced.

I'm not interested in a traditional pot, rather a stepped/ladder type. There are several possibilities like: Single control like Khozmo 48 and 64 stepped; Shallco/Elma 24/48/64 twin mono; and some three knob systems like the Glassware. I think attenuation is important to sound quality. Most of these components have unique chassis mounting requirements, and they're not cheap. So whatever I end up buying will have to be permanent.

Any suggestions would be welcome.

Nothing is permanent ! We visit for a period and fade out, our things we make will usually have even shorter lifetime. A thing made to "last forever" might be the thing that keeps one in the dark hole with no hope of getting better...