toddalin
01-09-2020, 07:51 PM
We've started to do somewhat regular open houses listening to peoples stuff here in So Cal. To be able to compare stuff, I'm assembling the Ultimate Switcher allowing A/B comparisons, via wireless remote, of any two sets of speakers, amps/integrateds/receivers, preamps/intermediate processing hardware, and sources that operate at line level. Turntables can also be done, but would probably be sensitive to hum. The box will also allow for comparison of intermediate processing equipment against nothing (e.g., is the piece adding audible noise/distortion).
All options will include the ability for level matching (up to 20 dB difference) with switchable "tell tale" indicators. Amps not under scrutiny at that moment will dump their load into dummy load resistors so tube amps may be used, and even compared directly to solid state amps. Additionally, the amp not being auditioned (i.e., dummy loading into the resistors) can be attenuated by up to 20 dB at its input.
I am trying to use only high quality pieces in the signal chain including Aromat signal relays, Alps potentiometers, and Dale resistors. Speaker switching relays will be able to handle a minimum of 10 amps. All speaker grounds (at the amp outputs) float independant of each other.
http://www.audioheritage.org/photopost/data//500/medium/ScreenHunter_223_Jan_09_15_49.jpg
All options will include the ability for level matching (up to 20 dB difference) with switchable "tell tale" indicators. Amps not under scrutiny at that moment will dump their load into dummy load resistors so tube amps may be used, and even compared directly to solid state amps. Additionally, the amp not being auditioned (i.e., dummy loading into the resistors) can be attenuated by up to 20 dB at its input.
I am trying to use only high quality pieces in the signal chain including Aromat signal relays, Alps potentiometers, and Dale resistors. Speaker switching relays will be able to handle a minimum of 10 amps. All speaker grounds (at the amp outputs) float independant of each other.
http://www.audioheritage.org/photopost/data//500/medium/ScreenHunter_223_Jan_09_15_49.jpg