Originally posted on the Lenco Heaven forum August 2011
I just thought I would take advantage of the summer lull to relate the story of my journey from Lenco to Salvation. I used to contribute regularly on the old Lenco Lovers forum (can I mention that? ) but have moved on from the Lenco. I do regularly lurk on the forum to see whats new, & have many friends I have made from here who I correspond with on a regular basis.
The point of my posting is merely to describe the experiences I have had that led me to the final Salvation design.
My main turntable had been a Gyro.....decked out with the Pedersen Mod......
This served me well for years until I got the urge to explore idler rim drive. Not quite sure how, but I stumbled on the old Lenco Lovers forum which was inspirational.
My first effort, simple plywood multilayered plinth:
Actually, a lot of messy work was involved in making the multilayered affair, so I chose the easy way out with my next effort:
Although the sound of these decks exceeded the performance of my Gyro, the thing that I obsessed about was the motor noise intrusion, both electrically & mechanically.
For my next experiment, I decided to utilise the Lenco components with a Gyro belt drive. Looking back on efforts, it was a pretty stupid idea......nevertheless, the guys on Lenco Lovers were encouraging , & no one actually came out to say the idea was bonkers!
My first deck I used a multi-platformed plinth affair in an attempt to isolate the motor vibes from reaching the platter:
The motor was mounted to the bottom plinth using a rubber band suspension system for isolation:
To run the belt, I cut some grooves on the shaft using a mini-lathe. This was tedious as the groove depth had to be the correct diameter to run at 33.3rpm......lots of trial & error:
The whole contraption worked rather well, but it was too complicated. My next effort the brief was to simplify the plinth arrangement and suspend the motor from the plinth.
........A simple twin layered plinth in the shape of a triangle, dubbed ‘Lenco-blerone’. It was also found the suspension system I had devised for the motor was so effective I could mount direct to the plinth. No vibes got through to the platter.
I did not like having the point of the triangle facing me during operation....it put too much distance between me & the record. A modification was done to reposition the deck with the flat facing forward, & an arm board mounted on the side:
Dumping the Lenco chassis & using the motor at the side was a field day for creativity. A few other designs that materialised on the same theme, the ‘Lenco-burger’:
....and a single layered ply plinth:
For my next experiment, I decided to utilise the Lenco components with a Gyro belt drive. Looking back on efforts, it was a pretty stupid idea......nevertheless, the guys on Lenco Lovers were encouraging , & no one actually came out to say the idea was bonkers!
My first deck I used a multi-platformed plinth affair in an attempt to isolate the motor vibes from reaching the platter:
The motor was mounted to the bottom plinth using a rubber band suspension system for isolation:
To run the belt, I cut some grooves on the shaft using a mini-lathe. This was tedious as the groove depth had to be the correct diameter to run at 33.3rpm......lots of trial & error:
The whole contraption worked rather well, but it was too complicated. My next effort the brief was to simplify the plinth arrangement and suspend the motor from the plinth.
........A simple twin layered plinth in the shape of a triangle, dubbed ‘Lenco-blerone’. It was also found the suspension system I had devised for the motor was so effective I could mount direct to the plinth. No vibes got through to the platter.
I did not like having the point of the triangle facing me during operation....it put too much distance between me & the record. A modification was done to reposition the deck with the flat facing forward, & an arm board mounted on the side:
Dumping the Lenco chassis & using the motor at the side was a field day for creativity. A few other designs that materialised on the same theme, the ‘Lenco-burger’:
....and a single layered ply plinth:
At this stage Ian came over to compare my belt drive efforts with his Stanley. After an afternoon of careful listening, we both agreed his Stanley had better pace & bass.
It was back to the drawing board for me.........😟
I decided to come up with a system to drive the platter from the side, but using an idler rim drive. I combined the suspension from the belt drive with the Lenco idler:
It was back to the drawing board for me.........😟
I decided to come up with a system to drive the platter from the side, but using an idler rim drive. I combined the suspension from the belt drive with the Lenco idler:
This was a self contained motor pod which would drive the Lenco platter from the side. It would only run at one speed, though, but was pretty quiet, although not Gyro quiet! I converted the Lenco-burger to this rim drive:
This combination gave me back the bass & pace of the rim drive but less motor vibes.
I felt this was as far as I could go with the Lenco motor & was itching to try a DC motor in this configuration. I had an Origin Live motor & controller I was using with the Gyro, so cannibalised this to make a new motor pod:
I felt this was as far as I could go with the Lenco motor & was itching to try a DC motor in this configuration. I had an Origin Live motor & controller I was using with the Gyro, so cannibalised this to make a new motor pod:
It was at this time I consulted with Frenk, an authority on DC who was fooling around with DC motor drive for the Lenco. He suggested using a flywheel for stability in this configuration as can be seen by the huge brass pulley.
This was the best sounding deck yet, with all the pace & magic of the Lenco, had 2 variable speeds, but was quiet like a Gyro! I loved the design so much, I made another using Lenco-burger using oak:
This was the best sounding deck yet, with all the pace & magic of the Lenco, had 2 variable speeds, but was quiet like a Gyro! I loved the design so much, I made another using Lenco-burger using oak:
This was my primary deck for a long time. My creativity was being diverted into revamping the Ladegaard arm into something that would work better with shallow platter (ie Lenco). Eventually Terminator was born with an inverted bearing & underslung carriage allowing it to work with the shallowest of platters.
In the meantime, I had been reading much about the Garrards & the new slatedeck plinths. When one appeared for the Lenco on ebay at a knockdown price, I made a beeline for it & immediately mounted a Lenco chassis onto it:
In the meantime, I had been reading much about the Garrards & the new slatedeck plinths. When one appeared for the Lenco on ebay at a knockdown price, I made a beeline for it & immediately mounted a Lenco chassis onto it:
The sound of this deck stunned & shocked me. I could not believe what I was hearing. As much as I loved wood, if what I was hearing was due to the slate, wood was dispensable. I have to admit from that day, I have not made another wooden plinth!
I schemed to make a deck using my DC motor pod, slate plinth & Lenco platter/bearing. This was my first mockup:
.............and realisation:
I schemed to make a deck using my DC motor pod, slate plinth & Lenco platter/bearing. This was my first mockup:
.............and realisation:
It starting to look a bit ‘Salvationy’....but I had a way to go yet. Round about this time, I started to get curious about direct rim drive. Enter the Teres Verus.........
The leap to this motor was almost as great as from Gyro belt drive to Lenco rim drive. I took this motor apart to investigate what it was making things sound sooooooo great. Experiments driving the platter directly or through an idler wheel showed that the magic was lost when the idler was introduced:
Now, there are MANY problems to overcome when you try to drive a platter directly from a motor shaft. A couple that spring to mind being the motor speed & transmission of vibrations from the motor through to the platter. In the case of the Verus, the motor is spinning at under 200rpm to drive the platter at 33rpm. No motor is going to be stable at that slow speed, but the Verus uses some very advanced electronics to create rock solid stability. I was certainly out of my depth here, but wondered if there was a simpler way. Using an interim idler wheel between the motor shaft & platter rim solves all the problems of gearing, speed change & vibration transmission in one hit.....but just doesn’t sound as good.
One of the major problems I had was manufacturing a pulley with integral O-ring that was accurate enough to work silently. Even the Verus suffers with this problem. The slightest eccentricity or flat spot will be heard through the platter as a ‘heart-beat’ at best, or rumble at worse. It is quite easy to machine a pulley with accuracy required, but once you mount the O-ring, everything is lost.
I developed a technique to grind the the O-ring on the lathe to achieve the accuracy required. Although a time consuming process, it worked well.
The leap to this motor was almost as great as from Gyro belt drive to Lenco rim drive. I took this motor apart to investigate what it was making things sound sooooooo great. Experiments driving the platter directly or through an idler wheel showed that the magic was lost when the idler was introduced:
Now, there are MANY problems to overcome when you try to drive a platter directly from a motor shaft. A couple that spring to mind being the motor speed & transmission of vibrations from the motor through to the platter. In the case of the Verus, the motor is spinning at under 200rpm to drive the platter at 33rpm. No motor is going to be stable at that slow speed, but the Verus uses some very advanced electronics to create rock solid stability. I was certainly out of my depth here, but wondered if there was a simpler way. Using an interim idler wheel between the motor shaft & platter rim solves all the problems of gearing, speed change & vibration transmission in one hit.....but just doesn’t sound as good.
One of the major problems I had was manufacturing a pulley with integral O-ring that was accurate enough to work silently. Even the Verus suffers with this problem. The slightest eccentricity or flat spot will be heard through the platter as a ‘heart-beat’ at best, or rumble at worse. It is quite easy to machine a pulley with accuracy required, but once you mount the O-ring, everything is lost.
I developed a technique to grind the the O-ring on the lathe to achieve the accuracy required. Although a time consuming process, it worked well.
With the motor pod design I decided to go with the Verus type gravity system rather than my rubber band system. This was simple to implement, although I had to encorporate some kind of lift system to disengage the drive wheel from the platter when not in use to avoid flat spots.
My first prototype next to Verus:
My first prototype next to Verus:
Detail of hinge arrangement showing simple cam lever mechanism:
I should point out I have a workshop in my garage with a small mini lathe & mill which will allow me to make simple working prototypes to experiment with.
I stuck the Origin Live motor in this pod, & operated with its power supply & controller:
By this time I had also ditched the Lenco platter & bearing for something I sourced from the Far East which was easier to work with having flat sides! I had one of those OMG moments when I switched platters. You wont like the next bit but it sounded one helluva lot better than the Lenco platter/bearing combo, & even my Gyro platter/bearing! I put this down to the acrylic platter which sounded so dynamic & live!
Anyway, this motor worked.....but not very well because it tended to fall off its hinge. It was too tall, too light & the pivot points were not spaced far apart enough.
My next prototype addressed the issues:
........but the base was still too light. This was solved using a slate base:
Anyway, this motor worked.....but not very well because it tended to fall off its hinge. It was too tall, too light & the pivot points were not spaced far apart enough.
My next prototype addressed the issues:
........but the base was still too light. This was solved using a slate base:
......but this was too expensive!
Eventually, the base was redesigned to encorporate the lift mechanism & was machined out of a solid billet of aluminium. This was my first production prototype which I was very proud of!
.....however, the speed was not stable & was affected by stylus drag which is greater at the beginning of the record than at the end, so the record tended to speed up as the stylus approached the inner grooves.
The main problem was using the motor in this direct rim drive configuration meant that it had to run relatively slow. In my case, I was running a 32mm pulley which was the minimum size I could use to clear the motor pod & make contact with the platter. This meant the motor was running at 300rpm, using only 7V & was not generating enough torque.
I tried various mechanical means to create drag. At first, grease instead of oil in the bearing. This would work initially, but I found as the grease warmed, its drag capability diminished. I tried all sorts of greases & additives. Some were stable for 2 weeks, & I thought I had the found the solution, but eventually they broke down too & became unstable.
I then played around with an oil braking system........
The main problem was using the motor in this direct rim drive configuration meant that it had to run relatively slow. In my case, I was running a 32mm pulley which was the minimum size I could use to clear the motor pod & make contact with the platter. This meant the motor was running at 300rpm, using only 7V & was not generating enough torque.
I tried various mechanical means to create drag. At first, grease instead of oil in the bearing. This would work initially, but I found as the grease warmed, its drag capability diminished. I tried all sorts of greases & additives. Some were stable for 2 weeks, & I thought I had the found the solution, but eventually they broke down too & became unstable.
I then played around with an oil braking system........
.....a magnetic system....
....all with limited success.
By this stage i was losing alot of hair...........!
A friend of mine suggested some method of electronic control. My knowledge of electronics is extremely limited. However, I had managed, with help, to make a very stable, simple & clean variable voltage DC supply that sounded great. It was a big surprise to me that the type of output capacitor on this controller affected the sound of the turntable......so several capacitors were tried to tune the sound.
By this stage i was losing alot of hair...........!
A friend of mine suggested some method of electronic control. My knowledge of electronics is extremely limited. However, I had managed, with help, to make a very stable, simple & clean variable voltage DC supply that sounded great. It was a big surprise to me that the type of output capacitor on this controller affected the sound of the turntable......so several capacitors were tried to tune the sound.
This simple board was replaced with a feedback control board which sensed the speed of the motor & compensated for stylus drag.
This was an amazing update. You could feel the motor fight with you as the spinning record was cleaned with a dust brush! Speed was finally stable too & drift was banished! At last, I had found the solution!
.............BUT, I was not happy. Something had happened to my sound. The bass was not as snappy & tight as I was used to, & music had lost focus & became smeared. Was the feedback control doing this? It would appear so, because when I put my linear supply back on, everything was restored.
At this point, it appeared the compromise I would have to accept was either a great sound with speed drift, or a worse sound with speed stability.
I chose the speed drift for many months. By this time though, I was getting enquiries from Terminator clients who were interested in the turntable, so felt a bit of pressure to find a solution that would mean great sound & speed stability.
I reasoned I had to get the motor spinning faster. I could not reduce the size of the drive wheel anymore, but could increase the size of the platter! Lets have a go!
.............BUT, I was not happy. Something had happened to my sound. The bass was not as snappy & tight as I was used to, & music had lost focus & became smeared. Was the feedback control doing this? It would appear so, because when I put my linear supply back on, everything was restored.
At this point, it appeared the compromise I would have to accept was either a great sound with speed drift, or a worse sound with speed stability.
I chose the speed drift for many months. By this time though, I was getting enquiries from Terminator clients who were interested in the turntable, so felt a bit of pressure to find a solution that would mean great sound & speed stability.
I reasoned I had to get the motor spinning faster. I could not reduce the size of the drive wheel anymore, but could increase the size of the platter! Lets have a go!
VIDEO IN ACTION
Enter the Uber Platter!
This was a mega monster with a 14” diameter & weighing 9kg!
Not only did this give the Salvation a huge authoritative sound, it also reduced speed drift to an acceptable < 0.3%!
For the final production Salvations the drive system & electronics have been further tweaked to improve the sound & increase speed stability.
One of the main problems I had was producing an O-ring for the motor idler that did not thump. Machining the rubber was hit and miss....not only that, but if I managed to produce a perfect idler that did not thump, it did not remain so. The rubber was not stable.
I racked my brain for a solution when I suddenly thought.....why not transfer the O-ring to the platter so the idler could just be a one piece solid unit? This solution proved to be revolutionary, and is what you see today. I maintain this direct idler drive system, with the traction belt on the platter, remains unique to Salvation. I am not aware of any other manufacturer ever producing such a system, and is when gives this deck its solid, dynamic sound.
The motor idler size was reduced to around 10mm which allowed the motor to run at 20V which further improved torque and speed stability, but did not increase vibrations.
The journey has taken a long & tortuous path, but I have learned much from the experience. All I will say is Salvation has satisfied ALL my creative audio desires!
Below is latest iteration with Panzerholz plinth, carbon manifold, stepped platter, suspended wand and Isoplat. You may have noticed I am using a Gophert bench power supply for the motor on the left (the right one powers phono stage). One of my clients played a lot of 45rpm records and asked if something could be done without swapping idler. With Salvation, because the power supply was limited to 20volts with fine adjustment only, a larger diameter idler wheel needed to be swapped over to achieve 45rpm. This was clearly a pain & I reasoned if the voltage could be increased, would the 33rpm idler achieve 45? Clearly it did @ 27Volts. I think with a higher voltage power supply it would reach 78rpm too, but that might affect the Time/Space continuum! The motor, BTW, is good for 48V.
Below is latest iteration with Panzerholz plinth, carbon manifold, stepped platter, suspended wand and Isoplat. You may have noticed I am using a Gophert bench power supply for the motor on the left (the right one powers phono stage). One of my clients played a lot of 45rpm records and asked if something could be done without swapping idler. With Salvation, because the power supply was limited to 20volts with fine adjustment only, a larger diameter idler wheel needed to be swapped over to achieve 45rpm. This was clearly a pain & I reasoned if the voltage could be increased, would the 33rpm idler achieve 45? Clearly it did @ 27Volts. I think with a higher voltage power supply it would reach 78rpm too, but that might affect the Time/Space continuum! The motor, BTW, is good for 48V.
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NOVEMBER 2023 Updates
Latest update here. In my obsession to reduce rumble, I created the ISOPLATTER. This was very effective, and very little rumble could be heard through the speaker. Nevertheless, rumble could be 'felt' coming through the woofers if I touched the cones on the run-out grooves of the record.
Luckily, the cones are within reach of the motor pod so I could outstretch my arms and reach both at the same time. Isolating the metal pod by resting on different types of foam would alter the strength of the vibes coming through the woofers, some being more effective than others. Moreover, if I held the motor pod in my hand and held against the platter, the vibes practically disappeared. This told me the vibes coming from the motor itself were minimal, but the metal pod resting on the slate platform was somehow amplifying the vibrations. My idea was try various forms of motor suspension that would quell the vibrations. The picture below shows the different permutations the motor pod went through, starting with the metal pod/base, rubber base/ O-ring suspension, Hard foam & finally Soft foam:
The soft foam proved to be very effective, with hardly any vibes coming through the woofers. This was easy to test by simple disengaging the drive wheel from the platter. One thing I did notice was that some records are quieter than others..... rumble was actually recorded into the grooves!
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After discovering I could quell the vibration from the motor by using a lightweight foam motor pod, I decided to look at the rest of the suspension system for the deck.
Salvation rests on MagLev feet which basically consists of powerful magnets repelling each other:
From the diagram you can see that although the magnetic repulsion will offer a suspension, the magnets will touch the sides of the cups. This creates a direct path through which vibration will travel. It is not possible to eliminate this contact because the repulsion of the magnets is not stable, and all the designs of this type of MagLev suspension will have some sort of stabilisation method, be it a shaft or enclosing cup as above.
I think a much better system in this application would be a rubber O-ring suspension similar to this:
The rubber O-rings are the only thing connecting the plinth to platform it sits on. There is no hard contact, so should provide TOTAL isolation.
I set about to test my theory with a similar system which I knocked up in the workshop:
Dialling in was a bit tricky as I discovered because all three of the legs needed to support different weights with basically the rear leg taking twice the load of the front pair. The Left front leg was taking slightly less load than the Right one because this was being offset by the weight of the Terminator. Luckily, this system lends itself to adaptation. Using different number of O-rings and different tensions sorted this, plus I had a height adjustment knob which I could use to fine tune.
Testing was revealing. Not only was the background quieter, but tapping the shelf that supported Salvation resulted in no noise breakthrough! This was a pleasing outcome and I spent the next few hours listening to my favourite records. The system sounded the best it had ever done.
I was annoyed that some records I could hear rumble, but this turned out to have been recorded into the vinyl grooves themselves, presumably at the time the record was cut as the rumble persisted even after I disengaged the motor. Hmmm.....
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SUMMARY OF THE LATEST UPDATES TO SALVATION THAT HAS TRANFORMED THIS DECK
I thought I would do this summary for clarification. All these updates have been done to try to minimise vibrations getting through to the stylus which IMO is one of the most important factors to influence performance.
1. Magnetic bearing update:
This was the oldest update. The idea here is to eliminate the bearing thrust-plate which is a physical contact which can generate mechanical noise due to its rotation, and also creates a direct contact with the plinth through which vibrations can find its way to the stylus.
This was simply done by a pair of powerful ring magnets, one attached to the base of the platter, and one to the bearing cup which was modified to accept the magnet:
2. Magnetic feet update. Similar as above, but with feet:
Won't spend much time on these as were recently superseded. Again, the idea here was to separate physical contact between the plinth & whatever Salvation was resting on.
3. Isoplatter
This was a breakthrough for me.....isolation the record from the platter surface. This would provide an extra layer of separation to prevent vibes getting from the platter to the record surface. Resomat already did this to a certain extent, but in common with all turntable mats, does not isolate the spindle. Here I created a 'false' spindle which is not in contact with the platter spindle.
This Isoplatter went through various prototype stages to reach this final design. Here we were getting CD-like silence between the tracks!
4. Suspended wand
Another break-through...again..... trying to minimise vibration reaching the stylus through the tonearm. Although the Terminator wand is supported by a cushion air, the gap is too small to prevent low frequencies from getting through.
Here, adopting a twin rail design allows the headshell & counterweight to be suspended on O-rings:
Some people out there say a tonearm should be rigid everywhere to ensure the cartridge does not move so the grooves in the record may be faithfully reproduced. I think more is to be gained by preventing extraneous vibrations from reaching the cartridge. I have not noticed any detriment to having a floating cartridge, only benefits!
5. Foam motor pod
This may seem a bit strange, but I discovered raising the motor off the platform it shared with the turntable noticeably reduced vibes that could be felt by touching the woofer cones.
I went through various motor pod iterations from the original metal bases heavy aluminium pod, to rubber based AL pod, to O-ring motor suspension to stiff foam & finally light foam..
Vibrations from the motor & this system of direct idler drive has always been a bugbear of mine. I resigned myself to the fact this was always and issue, and although it was quieter than the Garrards & Lencos I had had in the past, it was never going to be as quiet as my Gyrodec. I need to quantify I am running subwoofers that go down to 20Hz, and that most people would not be so OCD about it. From the seating position with the mods I had already done, there was no noticeable noise in between tracks, certainly below vinyl roar. I was surprised that separating the motor from the slab of slate it shared with Salvation had such an effect on motor vibes. I can only conclude the heavy original pod was somehow amplifying the motor vibes and transmitting it through the slate up the magnetic feet and into the stylus. So much for mass and sinking vibration. The light, soft-touch approach paid dividends here.
6. Finally, O-ring Suspension: my latest mod with replacement of the MagLev feet.
Following on from the Foam Motor Pod trying to break the vibration path to the plinth. These O-ring feet provide another layer of isolation and proved to be way more effective than the MagLev feet, virtually eliminating motor-vibes being felt at the woofers. There is more rumble recorded into the vinyl from the cutting lathe than what is getting through from my motor!
All I would say is you can't have enough isolation with vinyl. These mods have brought my vinyl-rig in line with my digital set up, matching resolution, detail & soundstage. Doing A/B comparisons of the same track I would say the vinyl is a touch warmer and obviously, some records are noiser with clicks & pops. The Puffin Digital Phono Stage I use is effective at reducing them, and the Goldring 2500 cartridge is renowned for having very low surface noise, so playing vinyl is a very enjoyable alternative to streaming & CD's.
Will keep updating this blog should I think of any other ways of isolating!
PS. By the way, I did try isolating the mounting column for Terminator, but this was not a success. Resolution & dynamics seemed to suffer, so maybe isolating everything is not a good idea.....
To Summarise, what I learned in TT design:
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UPDATE DECEMBER 2023
Now that I had reduced noise level of Salvation I decided to turn my attention to the drive mechanism....in particular, the drive wheel. This historically was set at 11mm diameter which gave a speed of 33.3rpm at round 20V. I while back I changed the power supply to a Gophert CPS-3205 which reached 45rpm without changing drive wheel as this PS would reach the 27V required for 45rpm.
Anyway, the fact that this PS would reach 32V motivated me to attempt 33.3rpm with a smaller drive wheel and what effect this would have on the sound. I found a diameter of 7mm gave a speed of 33 @ 31V.
Effect of this increase in volts was remarkable. Big increase in dynamics. Leading edges became more percussive and defined resulting in and increase in bass detail and texture.
Of course, requiring 30V to reach 33rpm meant I could no longer get 45rpm and I was near the maximum limit for this power supply. I have ordered the 60V version which will allow a higher speed which I estimate to be around 38V. I will report back on this, but the motor is well within its limits of 48V max.
At this stage I decided to service the bearing and replace the oil. I had been using Mobile SAE30 synthetic, but after researching I found most people were using DTE oil (as recommended by Thorens) which is slightly thinner.
After servicing and modifying the idler wheel, it was time for a speed stability & WOW test using my phone app. The effect of these changes was dramatic. Speed stability was never Salvation's strong point, and many attempts to correct with electronic feedback & other means all had a detrimental effect: the magic the direct idler drive system brought to the table was noticeably compromised. Now, she holds her own, and is on a par with the Garrard 301:
Ok, I finally found the solution to belts being thrown off the platter while rotating. I always assumed this would not happen if everything was perfectly level. In fact, the motor needs to be slightly higher on the left side than the right. This seems to solve the issue:
Getting the platter level in all planes is essential to optimise performance of the magnetic bearing and ensure friction is minimal. This tool was easy & reliable to use, and having a readout to tell me how far I was off made levelling a much less laborious task!
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Have now revised Salvation with a new shaped wooden plinth.
The original plinth design was based on non-suspended hard feet. Using the old plinth on suspended feet means the back foot is taking a much higher weight. The new design balances the weight evenly on all 3 feet, so the bounce is even and synchronised. Photos to illustrate:
Warm regards to all!
Vic
Vic