Regarding Turntable

The Dual 1219 Likes the Stock Mat

Recorded on April 4th, 2016

photo of LP on Dual 1219 turntable

After the inner-rim polishing experiment last night, I was able to do more listening today. Without a doubt, the noise floor is vastly lower with the polished inner rim. I’ve finally nearly achieved the same inky-black background with the Dual 1219 that I loved with the Thorens TD-165. When I crank up the volume, I can faintly hear the rubber idler driving the inner rim, but it’s way quieter than it was in the past. And when I put my ear up to the platter to listen to it “airborne”, the only thing I can hear anymore is the motor. No whirring/turning from the idler + rim interface.

With that improvement in the bag, the other big a-ha moment today was going back to the stock Dual mat. Until now, I had a thin strip of drawer-liner mesh from Target lining one of the voids in the mat, to deaden the space underneath a record and give it some buffer from the metal platter. With everything quieter in the first place, I thought I’d remove that strip of mesh. Immediately, everything got brighter and more alive. It was like night and day. A vinyl record must want to have the solid, hard foundation of the the stock Dual rubber mat. Even better than that, as shown in the photo above, I made a “clamp” from a wine bottle cork, a small sheet of mesh, and a circular scrap of leather. I put that on the spindle and it pushes the disc down to the mat. The important thing to remember is that stereo grooves are not just lateral. Half of the groove wall information is contained in an up-and-down axis, so you really want a hard surface supporting the record. It might have been quieter having a more squishy mat underneath, but I’ll take a hint more rumble if it means crystal-clear highs come with it.

You may want to say, “But why don’t you just put a hockey puck or a weight on the record if you want to press it against the mat?” Ah, yes, I have a hockey puck. But it’s a little too heavy, and anything with enough mass to use gravity to press the record down is also going to drag the platter. I’ve done it, but the sound loses its life, and sometimes I can even hear it slow down. The trick with the cork + mesh scrap + leather scrap is that it weighs almost nothing, but it hugs the spindle cap and pulls the record down close to the mat, so there’s no air gap, no give, and no resonance. The vinyl stays coupled to the mat radially, and up and down.

I also fixed the tonearm wire so that the side forces on the arm were more equal from either side of the pivot. It’s not perfect – I need to get some more lightweight Litz wire from England to replace the relatively stiff, shielded, cannibalized FireWire arm wire – but it’s better.

The result for now: The Doobie Brothers sound like they’re in the room. Totally hallucinatory.

Dual 1219 Inner Rim Polished with Good Results

Recorded on April 3rd, 2016

photo of Mothers Mag & Aluminum Polish

I couldn’t leave well enough alone and had to get out the metal polish tonight. I was inspired by this old post from Seth (a.k.a. NoTransistors) on AudioKarma, where he recommended polishing the inner rim of Dual idler turntables to a mirror finish. I liked the idea of it for reducing rumble, but was afraid it would make the idler rubber less grippy. Well, I should have done it long ago, because it sounds excellent. I didn’t get it quite as smooth as mirror-shiny, but after a bunch of times around it with some Mothers Mag & Aluminum Polish and some pieces of old t-shirt, it’s way smoother now than when it came out of the factory.

It must be something about the tiny contact area where the idler meets the rim that likes a buttery-uniform transfer of power through the whole revolution of the platter. The high-frequencies were unleashed and I could hear the actual tip of the drumstick on the hi-hat in the right channel on “Here to Love You” by the Doobie Brothers. That definitely didn’t come through before. It’s like the detailed goodness of a belt drive combined with the underlying force of an idler. I think it’s quieter now, but it was so windy tonight that it was hard to evaluate background noise. I’ll listen more tomorrow.

Unfortunately, my hands were too dirty to take any in-process photos of the polished rim. I was too excited about getting it done to think about taking pictures anyway. The gross photo above shows what cotton rags look like after polishing the platter.

Baerwald, the Conrad Hoffman Arc Template Generator, Wine, WineBottler, and Perfect Alignment

Recorded on March 24th, 2016

screenshot of Conrad Hoffman arc template generator software

Things have reached a new level of crazy in this house.

I had been using 1/4” of underhang on the DIY tonearm, with the AT120Eb mounted parallel to the arm, but with yesterday’s listening tests, I could hear that the cart was way out of alignment on the first couple of tracks on most albums. I could see it, too, but initially chose to ignore it, thinking that the trade-off in reduced side-force on the stylus would be worth it. It wasn’t.

Thus began what we call “hotbrain”, where I would do rapid-fire research on the iPhone and append every promising page URL to one entry in Drafts. That draft got quite long by the end of the hotbrain.

First was research into whether a 12” tonearm really needed an offset cartridge, or if straight would be good enough. I found a very religious, heated thread about “Tonearm without off-set” on Audiogon, where I learned that:

The sonic benefits of highly accurate alignment are huge. Search this forum for “Mint” or “MintLP” protractor for a wealth of information and testimonials across a wide range of tonearms and cartridges. You’d be shortchanging yourself not to have the best possible alignment, which won’t be feasible without a properly angled headshell.

This led to a hunt for the Mint LP protractor, a rather expensive custom-generator protractor they mail you after getting your turntable and tonearm model numbers.

Ah, but then this post about the Mint on the Steve Hoffman boards:

I own a Mint but prefer to use an arc protractor generated by Conrad Hoffman’s software, which is what I was using before I purchased the Mint.

Now I was fully converted to abandoning underhang in favor of using overhang + Baerwald alignment. The only problem was the highly-regarded – and free – Conrad Hoffman custom arc generator only ran on Windows. All I have are Macs.

This is where the crazy starts. I didn’t want to deal with downloading a copy of Windows and then a trial of VMWare to install the Conrad Hoffman software, so I was actually this close to signing up for a free trial of a Microsoft Azure hosted virtual machine. But then I read about the hurdles you have to go through to install third-party apps on such a service, and kept looking.

I thought later, “What’s the simplest thing that could work?”, and re-discovered Wine/WineBottler, a way to run some Windows programs on a Mac without installing Windows. I tried it, ran the Conrad Hoffman generator, and was surprised when it ran!

Only thing to figure out was what I wanted my spindle-to-pivot distance to be, since that’s the only parameter you enter about your own system. If I wasn’t doing underhang anymore, I had to come up with a suitable overhang for a roughly 12” straight arm. I found a post mentioning one of the Nanook 219 iterations, and someone said they designed theirs to have 14mm of overhang, and their arm was a similar length to mine. That seemed good enough, so I moved the arm pivot, measured the spindle-to-pivot distance as 308mm, and plugged it into the generator. Conrad’s readme file said that if you didn’t want to make a research project out of it, to just go with the DIN setting and Löfgren A (Baerwald). Those inner- and outer-groove measurements looked close enough when I measured a real LP.

I held my breath and clicked “Print Arc Template” and was relieved to see our wireless printer listed in the Windows print dialog. I clicked “Print” and heard printing noises starting up in the next room. I had to print one more copy after correcting for the Y-axis scale. I put it on the turntable, temporarily taped down the platter (per the instructions), lined everything up, and pretty easily got the cart aligned with the arc and the guides. I moved the stylus over a real LP and could see that the stylus was actually very closely aligned with the grooves all way way through the arc. Never got that close before.

I tightened it back in the headshell, put on Minute By Minute by the Doobie Brothers, and was carried away by the sound of perfect alignment all the way through the album side. It was involving and suspenseful, like a live performance that I didn’t know the outcome of. Every voice and instrument perfectly defined and weightless. I heard ambience cues that I never noticed before, and at the end of each song, lots of details that were masked previously. I’m a believer.

If you suspect you need alignment help, go for the Conrad Hoffman custom arc generator. And don’t be scared off if you have a Mac!

There’s a Spirit Level in the iPhone

Recorded on March 17th, 2016

A while back, I bought one of those small, round-bubble spirit levels to keep by the turntable. Your turntable must be exactly level so no unwanted side forces pull on the stylus as it rides across the LP. This avoids all kinds of terrible things: uneven wear as the stylus careens into the valleys of the groove walls and gouges into them, a bent stylus, unbalanced left/right signals, and a smeared stereo image. I won’t even talk about uneven stress on the platter bearing. You do not want any of this. You need a spirit level.

photo of spirit level

The level I have has worked ok’ish. As with a lot of the cheap ones, there seems to be some internal friction with the liquid inside it, so the bubble gets a little “stuck” until you tap the thing to loosen it up, and never seems to read the same thing twice. I’ve never fully trusted it.

I started this morning with a browse of The World of Bespoke Idler-Wheel turntables - Garrard, Lenco, EMT, etc. on Facebook, of course. While there, I was delighted to see a photo of Martina Schoener using an iPhone to level a L’Art du Son 301 Transcription Reference turntable. But what app was she using?

The built-in Compass app! She was on the initial compass screen, which has a tiny crosshair in the center relative to the larger crosshair to indicate how far out of level your phone is.

screenshot of Apple Compass app

That is pretty cool by itself. Even cooler is what happens when you swipe to the next screen to get to the dedicated bubble level. In real life, it moves around a bunch until you settle it down.

screenshot of Apple Compass bubble level

When you’ve leveled your phone, it turns green and looks like this.

screenshot of Apple Compass bubble level

It’s really sensitive, and doesn’t appear to get stuck like my physical level does. The one thing to watch out for with the iPhone is that pesky camera lens that sticks out of the back. If you have a hard case that smooths that protrusion out so it’s flush, you’re fine.

So, there. No need to buy ugly third-party spirit/bubble levels. It’s all built in, and has been there since iOS 7. Go forth and level that turntable.

The DIY Tonearm Actually Works

Recorded on March 16th, 2016

Not much more to say about this, other than sorry for the shaky video. And that I shall be consumed this weekend with ways to make a DIY tonearm lifter. There will be Delrin involved!

My Favorite Idler Wheel Turntables

Recorded on March 14th, 2016

Here are the idler wheel turntables I research repeatedly and drool over on YouTube the most. For more info about idlers and why they’re magical, read About TJN by Jean Nantais.

Dual 1219

My dad and I both have 1219s. His was the turntable I grew up listening to whenever I needed to hear something better than the 8-track stereo I had as a kid. Anytime you see people gushing over Duals, they always talk about muscle and impact. The 1219 has both, and with some tweaks to the wiring and a restored idler wheel, can be nearly Lenco-quality.

Garrard 301

When you hear piano rendered with rock-steady pitch like that, you know you’re listening to an idler. What a gorgeous machine.

Garrard 401

James Grant of Analog Instruments in New Zealand designs, fabricates, and sells his own high-end, stunning tonearms. Here’s a photo of an early version of his Apparition 12” arm, which I 100% copied for my own first DIY arm.

photo of Analog Instruments Apparition tonearm

My favorite videos of his are the ones where he demos a prototype of an arm on a Garrard 401. His designs are a perfect match for this amazing turntable. All of James’s tonearms are devastatingly good.

Lenco L75

Swiss. My holy grail. Someday I will have an L75. Because it is so great and transparent, you get two videos.

Neat Shield MO-19

I don’t have any videos of the Neat Shield MO-19, but I have it on good authority from my uncle Greg at AudioBoyz that this one is a sonic giant. If you ever see one at a yard sale, grab it!

Thorens TD124

Not strictly an idler wheel drive. It’s a combination of belt + idler, but boy, does it work well. I heard one this past summer and it is probably the best turntable I’ve ever experienced in person. Perfect combination of grace and drive. In this video, it just sails through the track.

The Return of the DIY Tonearm

Recorded on March 13th, 2016

photo of DIY tonearm

I got the bug again and bought an Audio-Technica AT120Eb to go with the DIY tonearm I made last year. I had given up on the arm because I didn’t want to move the Denon DL-110 from the Dual 1219 stock arm and all I had otherwise was an old used Stanton 681EEE cart of unknown lineage. I was actually afraid to play records with it because the stylus was in such bad shape, but I tested it on the wooden arm with a few LPs I didn’t care about. I knew the Stanton was hiding what the DIY arm could do. It sounded dull and unbalanced. Tonight I installed the AT120Eb and was blown away.

Everything about this tonearm was purposefully un-optimized because I wanted it to be a proof of concept. But even with the cheap/temporary choices and materials used (unvarnished cedar arm, a vise holding the Parker pen refill, a zip tie for a finger-lift, wiring cannibalized from an old FireWire cable, and a Craftsman wrench socket acting as a crude counterweight), this arm completely overwhelms the stock Dual arm (where the Denon cart still lives). I’m now a unipivot believer. Cymbals and vocals are focused and smooth, mistracking is gone, and there’s an air above everything where before it was suffocated. This setup sounds more like a Lenco L75 with an expensive arm than I thought was possible.

photo of DIY tonearm

I’m positive that all the improvements are not just because of the AT cart. It’s regarded as a great tracker, maybe even better than the Denon, but the huge correction in time alignment is something the cartridge can’t be responsible for by itself. The arm is just getting too many things right that the old arm couldn’t.

The only thing I think it’s missing for now is in the low end. It’s not as strong as with the Dual arm, but I think that once I shellac it or varnish it a bunch of times, it will firm up. It’s amazing that the soft cedar wood is able to sound decent at all. With some tweaks and with some break-in hours on the cartridge, it can only improve. There will be many more details to come, but for now, this project is a complete success. Everyone should try it. I don’t know why I didn’t do this sooner.

photo of DIY tonearm