Yes, they are nicely made with gold plated legs and socket terminals. The base feels like a sturdy heat resistant polymer.
MELF MMB is better for high voltage applications and these are great for high quality sound signal path applications.
One Japanese uncle told me that MELF sounds better than even Dale resistor , do you agree with that?
It skips the wire to end cap junction. The resistor itself is metal thin film inside a ceramic coating. I think they should sound great. They are used in automotive industry and aerospace for their ruggedness. Best sounding resistors are carbon film on feedback circuits and gate stoppers. 2mm Drafting pencil cores also make excellent audio feedback resistors.
On the bench tonight at the factory where the HyperDrive-2 is being assembled, is the test of the first article off the assembly line. My fingers are crossed. If this works, 99 more will be rolling off the line in days. Note the through hole DIP8 parts. We have massive parts shortages of SMT optically-isolated gate drivers to thank for that. Required a new board layout and lots of waiting. A big thanks to Jhofland for a superb design and layout. A huge thanks to SuperDarko for a sporty looking chassis. Great work by Jaclym and team in assembly and final integration of electronics and mechanicals. The tubes are Russian NOS 6N1P.
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Great news is the initial testing of the HD-2 is successful. All the buttons and LEDs light up and the relays click and clack. The graceful startup and shutdown with mute auto enabled works to prevent thump. The input selectors work, the (SSR) mute button works. The volume knob works. Most of all, the music is playing!
On the bench tonight is a second Bob Carver RPM V12 front panel and MCU with motorized alps pot board. The pot is a 4 gang to use as feedback for the position of the pot so we can have a memory of where the volume was set and allows random access volume via the remote control app. Plus a display of the current volume setting on the LCD screen.
Still more on the bench tonight are the aluminum IMS PCBs that are the SE Class A MOSFET source follower headphone amplifier output stage. These are mounted directly under the top deck heatsinks. Mouser was out of DPAK LM317’s so I had to modify a TH version for surface mount. The LM317 serves as the CCS for the source follower.
On the bench tonight is the Bob Carver RPM V12 main board connected to the PSU board. First power up test (no tubes) to check for power connections went well. Solid state Class A headphone amp output stages biases up just fine. Runs at 42C heatsink temp. The B+ pins at tube sockets all get the HV. The filament pins are getting their voltage.
Tonight I basically finished up doing a complete teardown and overhaul of a classic Dual 1009F turntable/changer.
I must have done hundreds of these Duals over the decades.
This old beast is in like-new cosmetic condition though, and running like brand new now.
Even the original walnut base is well cared for, and I have both the single play and stacker spindles too.
I might get a nice price for it once it's on my Craigs List site.
This photo is of the same unit I have.
I must have done hundreds of these Duals over the decades.
This old beast is in like-new cosmetic condition though, and running like brand new now.
Even the original walnut base is well cared for, and I have both the single play and stacker spindles too.
I might get a nice price for it once it's on my Craigs List site.
This photo is of the same unit I have.
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See post #875. Voice Coil is the periodical for loudspeaker industry. Some past articles are posted. Also Test Bench reviews are posted. Loudspeaker industry sourcebook view online for free.
I spent couple of hours going through the R audio after installing it on an RPi 3 with a Hifiberry DAC + ADC PRo hat, they have done a lot of upgrades and look nice UI. Did find a couple of issues but we will always find something here and there...
One thing that I wish was faster was Local display connected via the DSI port would be as snappy as the interface via the phone and this has plagued all other Distro's as well like Moode and Volumio and maybe PiCorePlayer.
One thing that I wish was faster was Local display connected via the DSI port would be as snappy as the interface via the phone and this has plagued all other Distro's as well like Moode and Volumio and maybe PiCorePlayer.
RPi as a streamer sounds like a lot of dIY fun.
I have some Khadas SBC’s which are like really powerful Linux with AI coprocessors. I also have a Volumio image specifically made for it but have not had time to play with it yet.
I am lazy and Amazon Music HD / UHD works well for me. 🙂
OTB tonight are some RIAA loading selectors for MM/MC configurations on the Bob Carver preamp V12. 0.5% Susumu 0603 resistors and nice NP0 caps to select gain and input capacitance and impedance.
Mounts like this:
Fits on rear panel like a glove:
Interestingly, I’m starting to work on driving the LSA Phono-01 MM/MC preamp into production. It has a similar DIP switch for setting input impedance, capacitance and gain.
Busy times.
I have some Khadas SBC’s which are like really powerful Linux with AI coprocessors. I also have a Volumio image specifically made for it but have not had time to play with it yet.
I am lazy and Amazon Music HD / UHD works well for me. 🙂
OTB tonight are some RIAA loading selectors for MM/MC configurations on the Bob Carver preamp V12. 0.5% Susumu 0603 resistors and nice NP0 caps to select gain and input capacitance and impedance.
Mounts like this:
Fits on rear panel like a glove:
Interestingly, I’m starting to work on driving the LSA Phono-01 MM/MC preamp into production. It has a similar DIP switch for setting input impedance, capacitance and gain.
Busy times.
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