Bo's words on the Cantus arm
There is of course lot of different ways to make a tonearm. My goal for Cantus is in short: The cartridge tip shall read the information in the trac, on the same spot as it was cutted, This is not possible with a pivoted tonearm. The cartridge shall have a stable reference and not be able to "swing" i.e. there shalll not be a fundamental resonance in the system. This is not possible with a pivoted arm. To solve this there is two contact points, which makes the carriage, hold the cartridge to can move sideway but not get in resonance. There shall not be resonators coupled to the cartridge, such as the "organpipe" resonance that is common on most existing tonearms. I mean that when you have a tube almost one feet long coupled to the cartridge, the tube itself resonates on two feet and four feet tones approximately 300Hz and 600 Hz and overtones on this. By making the tonearmtubes very short, the resonace is forced up to higher frequencies, and by using a very small diameter on the tubes the resonance is reduced significantley. You can easely hear the tonearm resonance when you put down the cartridge in a quite trac on the record. When you compare the sound from Cantus with most of other tonearms you will find Cantus playing teh empty track, much quiter than other. There shall not be any other kind of energi storing in the system, flexible materials. All mechanical energi shall be converted to electric output from the cartridge. The vertical movement from the record, shall be damped. In Cantus it's solved by using ballbearing with a little sideway play. This means the contact point in the bearing is changed when the tonearm moves up and down. As the contact point is changed there is automaticly a damping, because it's not a resonant point. This is perhaps difficult to understand, so please give it some time and thoughts. The Cantus shall be possible to mount on most of recordplayers/turntables on the market, having a affordible price for musiclovers who is more intrested in the music than equipment, and be easy to repair if accidents appears. The tonearm tubes is made of hard nonmagnetic stainless steel. "Music shall swing - not tonearms" 😱)! Sincerely Bo Hansson
Best regards Moray James.
There is of course lot of different ways to make a tonearm. My goal for Cantus is in short: The cartridge tip shall read the information in the trac, on the same spot as it was cutted, This is not possible with a pivoted tonearm. The cartridge shall have a stable reference and not be able to "swing" i.e. there shalll not be a fundamental resonance in the system. This is not possible with a pivoted arm. To solve this there is two contact points, which makes the carriage, hold the cartridge to can move sideway but not get in resonance. There shall not be resonators coupled to the cartridge, such as the "organpipe" resonance that is common on most existing tonearms. I mean that when you have a tube almost one feet long coupled to the cartridge, the tube itself resonates on two feet and four feet tones approximately 300Hz and 600 Hz and overtones on this. By making the tonearmtubes very short, the resonace is forced up to higher frequencies, and by using a very small diameter on the tubes the resonance is reduced significantley. You can easely hear the tonearm resonance when you put down the cartridge in a quite trac on the record. When you compare the sound from Cantus with most of other tonearms you will find Cantus playing teh empty track, much quiter than other. There shall not be any other kind of energi storing in the system, flexible materials. All mechanical energi shall be converted to electric output from the cartridge. The vertical movement from the record, shall be damped. In Cantus it's solved by using ballbearing with a little sideway play. This means the contact point in the bearing is changed when the tonearm moves up and down. As the contact point is changed there is automaticly a damping, because it's not a resonant point. This is perhaps difficult to understand, so please give it some time and thoughts. The Cantus shall be possible to mount on most of recordplayers/turntables on the market, having a affordible price for musiclovers who is more intrested in the music than equipment, and be easy to repair if accidents appears. The tonearm tubes is made of hard nonmagnetic stainless steel. "Music shall swing - not tonearms" 😱)! Sincerely Bo Hansson
Best regards Moray James.
Moray,
Thanks for that article, it makes a lot of sense and have noticed too with my arm the quietness on silent grooves due to lack of resonance. Also a huge speaker saving plus is that since its resonant frequency is higher its not prone to woofer pumping, as with the low q point of many pivoted arms. With my different bearing arrangement there is no side to side play but the vertical pivot system will also alter its contact points as it rides up and down the record. All this stuff involves trade offs of course, but from a dynamics, lowered audible tracking error distortion and imaging ,linear tracking seems to be the way to go to get even closer to the master tape 🙂.
Colin
Thanks for that article, it makes a lot of sense and have noticed too with my arm the quietness on silent grooves due to lack of resonance. Also a huge speaker saving plus is that since its resonant frequency is higher its not prone to woofer pumping, as with the low q point of many pivoted arms. With my different bearing arrangement there is no side to side play but the vertical pivot system will also alter its contact points as it rides up and down the record. All this stuff involves trade offs of course, but from a dynamics, lowered audible tracking error distortion and imaging ,linear tracking seems to be the way to go to get even closer to the master tape 🙂.
Colin
I agree with what you say. Bo did numerous demonstrations for industry reviewers where he would demonstrate playback of Opus 3 master analog tapes being played on the analog tape machine and amplifiers the tapes was made on with playback on the same amps and speakers the tapers were mixed with and compare those to his Opus 3 vinyl recordings played on the Continuo deck fitted with a Cantus tone arm. Bo was confident that you could not tell one playback from the other and so justified that more was not needed from an arm than equaling the master recording system. I cannot see using a pivot when you can make a linear that works this well. This is some kind of great hobby huh? Best regards Moray James.
Moray,
It's a fabulous hobby that can almost drive one insane. It's also crazy that for little money invested one can build an arm that performs as well as it does!. I had started building amps years back, did some work with Hugh of Aspen amplifiers, then went on to my own symmetrical current feedback designs but always wanted to nail this tonearm thing since its so critical to the sound with the table being as easy 2nd. Now the analog front end is no slouch to the rest, nothing but beautiful sound coming from my Martin Logan's at this point 🙂.
Colin
It's a fabulous hobby that can almost drive one insane. It's also crazy that for little money invested one can build an arm that performs as well as it does!. I had started building amps years back, did some work with Hugh of Aspen amplifiers, then went on to my own symmetrical current feedback designs but always wanted to nail this tonearm thing since its so critical to the sound with the table being as easy 2nd. Now the analog front end is no slouch to the rest, nothing but beautiful sound coming from my Martin Logan's at this point 🙂.
Colin
Vynuhl.addict
Very nice project, thank you for sharing. I am very much interested in pursuing in the near future. Please continue your excellent documentation and comments for improvement.
Very nice project, thank you for sharing. I am very much interested in pursuing in the near future. Please continue your excellent documentation and comments for improvement.
Many thanks SGregory!,
It's been a great experience, and another crash course in physics 101!. Of course in this hobby nothing is ever done, it's always a work in progress but I've been over the moon with the results and if anything it's the best learning tool. It's also great to look at all the other great ideas out there, and nice to be a part of A great forum as this to share ideas!. I've also got a split passive/active phono stage in my arsenal that is a real smooth performer which is a little nod to the Vendetta but an easy build based on some fine op amps opa637 and ad797.
Colin
It's been a great experience, and another crash course in physics 101!. Of course in this hobby nothing is ever done, it's always a work in progress but I've been over the moon with the results and if anything it's the best learning tool. It's also great to look at all the other great ideas out there, and nice to be a part of A great forum as this to share ideas!. I've also got a split passive/active phono stage in my arsenal that is a real smooth performer which is a little nod to the Vendetta but an easy build based on some fine op amps opa637 and ad797.
Colin
Here is a link to a short
Video of arm in action, I'll post a couple more.
Fast, Free Video Hosting & Video Sharing - VideoBam
Video of arm in action, I'll post a couple more.
Fast, Free Video Hosting & Video Sharing - VideoBam
Very nice project. Thanks for the vids. They go a long way to showing how well you build it. Don't know why but I was expecting to see some mechanical slop... mostly when you cued it up. I saw none. The arm seemed to move well. It looked precise. Congratulations!
Thank you pcb,
I've enclosed an end of side runout groove video to show the smooth roll, the lack of slop is all pivot point gravity 🙂. My iPhone doesn't like those last piano notes apparently so you will hear some distortion that is not there on those notes.
http://videobam.com/iHPxM
Colin
I've enclosed an end of side runout groove video to show the smooth roll, the lack of slop is all pivot point gravity 🙂. My iPhone doesn't like those last piano notes apparently so you will hear some distortion that is not there on those notes.
http://videobam.com/iHPxM
Colin
Off center record, note tube and bearing traverse and stylus centering
Fast, Free Video Hosting & Video Sharing - VideoBam
Fast, Free Video Hosting & Video Sharing - VideoBam
How does the vynuhl.addict arm compare with the Opus 3 Cantus arm? Is the
vynuhl.addict arm better or an improvement?
vynuhl.addict arm better or an improvement?
easy way for you to find out is to build both. Look at the parts list for both arms, consider the complexity of the two builds. Measure the finished moving mass of booth arms. Install the same cartridge and listen. After all that you can decide but your preferential choice might not be the same as the next guy. The only opinion that counts is yours, so far as what you like the sound of. Why don't you build an arm which seems to you to be the simplest linear design for you to make and start from there? Best regards Moray James.
Audio star,
I would love to hear the opus cantus, but sadly haven't had the opportunity but I'm betting it sounds wonderful setup well. My comparison is only with familiar music, and involvement with the music. As with every piece of gear I've built it must grab my attention.and make me want to relisten to my whole collection, not necessarily perfect measured sound but involving.. If I wanted perfect measured sound I wouldn't be building open loop amplifiers with dynamic bias and preamps, but they sound bloody amazing with realism that can make the hair on your arms stand up 🙂. Precision wise, there is smooth action without play or yaw while playing a record , smooth transition without overshoot due to the bearing layout and low mass in the lateral movement at least with a mid compliance cart as the at120e. Sound wise, it has all the traits that i desire, believeAble dynamics that don't leave me wanting some gestalt and solid imaging with tuneful bass, smooth mids and non grainy or veiled highs. Though of course all of this has to do with resonance control and getting a truer reading from the grooves.
Colin
I would love to hear the opus cantus, but sadly haven't had the opportunity but I'm betting it sounds wonderful setup well. My comparison is only with familiar music, and involvement with the music. As with every piece of gear I've built it must grab my attention.and make me want to relisten to my whole collection, not necessarily perfect measured sound but involving.. If I wanted perfect measured sound I wouldn't be building open loop amplifiers with dynamic bias and preamps, but they sound bloody amazing with realism that can make the hair on your arms stand up 🙂. Precision wise, there is smooth action without play or yaw while playing a record , smooth transition without overshoot due to the bearing layout and low mass in the lateral movement at least with a mid compliance cart as the at120e. Sound wise, it has all the traits that i desire, believeAble dynamics that don't leave me wanting some gestalt and solid imaging with tuneful bass, smooth mids and non grainy or veiled highs. Though of course all of this has to do with resonance control and getting a truer reading from the grooves.
Colin
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Cancelled the second one, mass is getting too high!. I've gone back to building a second copy of the first arm 🙂. This will be for a turntable project build!. Thank you for all the interest in this project and I'd urge anyone to give it a go 🙂, its worth it and easy to build.
Colin
Colin
I'm going to put together a plan and parts list, so that will be coming up. All parts are available between Home Depot, scientific supply store,and most hobby stores that cater to rc car builders.
Colin
Colin
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