Anything goes! Inventors! Artists! Cutting edge solutions to old problems. But also non-commercial usage of record cutting. Cost- effective, cost-ineffective, nutso, brilliant, terribly fabulous and sometimes fabulously terrible ideas.
More to follow soon. However, I thought everyone should know.... I just achieved flat response from about 200 hz to 20K hz. I fried my drive coil in the process. And, I have no video of the exact Eureka moment. But, I do have some footage taken just before. I'll be editing and posting a Caruso build up video tonight that will include test video shot just prior to ultimate success and coil failure.
Additionally, I will be building out two feedback transducers for further testing later.
Tonight's results were freaking fantastic!
Stay Tuned.
Cutting, Inventing & Innovating
Groove Graphics, VMS Halfnuts, MIDI Automation, Professional Stereo Feedback Cutterheads, and Pesto 1-D Cutterhead Clones
Cutterhead Repair: Recoiling, Cleaning, Cloning of Screws, Dampers & More http://mantra.audio
Haven't had time to build the phono pre board with switchable riaa. Psu and transformer are there and waiting. Just got proper rca connectors and the rest of the 1/4 jacks for the right channel caruso board. But, I have what I need to test feedback. Building more loop enabled transducers tonight! Further tests to come. But, given last night's progress, I think this should be a wrap soon and I can build out 1.H with stereo feedback for test cut.
Cutting, Inventing & Innovating
Groove Graphics, VMS Halfnuts, MIDI Automation, Professional Stereo Feedback Cutterheads, and Pesto 1-D Cutterhead Clones
Cutterhead Repair: Recoiling, Cleaning, Cloning of Screws, Dampers & More http://mantra.audio
I have some shielding. And, my transducer design itself provides a lot of isolation. Finally, I know how to make feedback coils correctly. Form follows function of course.
Cutting, Inventing & Innovating
Groove Graphics, VMS Halfnuts, MIDI Automation, Professional Stereo Feedback Cutterheads, and Pesto 1-D Cutterhead Clones
Cutterhead Repair: Recoiling, Cleaning, Cloning of Screws, Dampers & More http://mantra.audio
I can jam on the push rod with my finger and the response doesnt change a lot. I don't expect any issues making a full stereo feedback head. I'm actually really excited!
Cutting, Inventing & Innovating
Groove Graphics, VMS Halfnuts, MIDI Automation, Professional Stereo Feedback Cutterheads, and Pesto 1-D Cutterhead Clones
Cutterhead Repair: Recoiling, Cleaning, Cloning of Screws, Dampers & More http://mantra.audio
Todd, congratulations for the project, very inspiring. Have you ever tested how many dbs can reach in the frequency of resonance?
I liked the explosions, hahaha
These magnitude response visualizations are great, but a phase plot would be awesome to see! Thats is the kicker. Magnitude response doesn't mean much in this case if its shifted out of the useful range of phase coherence.
I know you know this
Keep up the great work! Looking forward to more updates
I'm showing you as much as anyone else is. More in fact...
Please tell me in detail exactly what you want me to do now.
If phase wasn't correct on the feedback signal, the negative feedback would act in reverse and would exaggerate the magnitude up or down. So, saying the magnitude plot shown in the video gives no indication of proper phasing is just not true. I know you know this.
If you saw huge dips or spikes or a raised plateau or a shelf in the magnitude plot then you know there are likely phase issues there. I'm not seeing that. Are you?
Cutting, Inventing & Innovating
Groove Graphics, VMS Halfnuts, MIDI Automation, Professional Stereo Feedback Cutterheads, and Pesto 1-D Cutterhead Clones
Cutterhead Repair: Recoiling, Cleaning, Cloning of Screws, Dampers & More http://mantra.audio
Hmm it appears I may be mistaken regarding what is being shown when you switch to the 'feedback' setting to display. I am not familiar with the caruso feedback board.
So when you switch between the two signal sources, you are switching between what exactly? Is it between the input signal and the feedback coil signal? Or is it between the input signal and the input+feedback sum. If its the latter than my recent response was misguided.
The caruso boards have a jack for monitoring feedback. That is before summing with input. So, I am switching between input and the feedback monitoring provided by the Caruso boards. Feedback is in some senses already summed with the input since feedback is only produced by stimulation via the drive coil and magnet which is representing/tracing the input.
Cutting, Inventing & Innovating
Groove Graphics, VMS Halfnuts, MIDI Automation, Professional Stereo Feedback Cutterheads, and Pesto 1-D Cutterhead Clones
Cutterhead Repair: Recoiling, Cleaning, Cloning of Screws, Dampers & More http://mantra.audio