Audio components manufacturing?

[great white]

I’m in to vintage audio. Part of that means vinyl records.
I’ve got a couple retail quality turntables, but I’d like to try building one myself.

It seems the tone arm is the biggest challenge as it needs to be weighted and balanced properly. “Professional” ones can run in the tens of thousands. Not sure who would pay that, but someone must or they would be out of business.

Has anyone here attempted such a project and if so, a few pointers woukd be appreciated.

 

[GeneT45]

I have not, but as an electronics engineer I have frequently laughed at the ridiculous (and un-quantifiable) claims made by those in the high-end audio market. (I'm saying "I", but it was really many of us at work, and we'd trade links to stupid junk like 'silver rock potentiometers, and 'acoustic varnish' and other such snake oil). I'd bet a dollar that any tone arm you made that was half-decent will perform as well as whatever umpty-thousand dollar BS is for sale...

Think the audiophiles claims are real? How 'bout the $700 kapton-insulated power cord - that you plug into your wall, where the power flows along $0.30/ft romex for a hundred yards.

High end audio is one of the biggest areas of hyperbolic claims and absurdity that I've encountered.

GsT

 

[homebrewed]

There are several challenges when it comes to making a turntable. One of the issues is the type of spindle used for the platter. You may have seen a "rumble" specification for turntables. That's low frequency noise generated by the spindle rotating. A spindle running with bearings will generate lots of rumble so you want a bushing in there. Another issue is the motor, it also needs to generate very low amount of noise while it's turning. That's one reason why most turntables are belt-driven, to reduce coupling between the motor and spindle. The periodic "push" of a brushed/brushless motor may introduce too much rumble. Then there's the challenge of getting accurate 33- 1/3RPMs for LP's. Another specification for turntables is "wow" -- frequency variations caused by variations in the RPMs. Variable drag on the spindle, perhaps due to machining marks, is one source of this. Of course, the drive motor has to be very stable, too.

Then there's the tonearm. I'd always thought that a so-called tangential style arm would be pretty good for a home-made tonearm. It avoids issues like the need for anti-skating mechanisms that pivot-based tonearms have to deal with. One elegant tangential scheme I read about was to place the tonearm on a slowly rotating rod. As the arm is pulled over by the stylus riding in the record groove, the rotation causes the arm to behave like a version of a "rohlix" style actuator so the arm follows the groove. You'd want to make sure that the runout groove doesn't cause problems with the arm, like causing the stylus to jump out of the groove. Electronic methods would work too but the rotating-shaft scheme is pretty darned elegant. As for the motor/spindle issue, rumble from the shaft drive mechanism and motor could be a problem, too.

One problem I see for the rotating shaft approach is figuring out a relatively easy way to return the arm back to its starting point. The most straightforward would be to do it manually. Using the Rohlix-style setup as a real linear actuator would permit the use of a more automated return scheme, but then you need some sort of feedback to keep the arm lined up on the record groove. Then there's the issue of the wires coming out of the phono cartridge, they can't introduce much drag on the arm or the tracking won't work right.

I don't see why all these challenges can't be solved with some careful choices of components and good design/machining. I think the biggest challenge would be to reduce the rumble induced by the spindle+motor (and maybe tangential) mechanisms. Due to their nature phono cartridges are very sensitive to vibration.

 

[great white]

Yeah, i’ve akways taken the 5,10,15,20 grand tone arms as a “there’s one born every minute” sort of things…

 

[great white]

fancy!

 

[tq60]

My favorite was the speaker wires with fine strands on the outside with larger ones in the middle, monster cable maybe?

They claimed skin effect caused the high frequencies to go outside and ride the finer strands.

Not at audio frequencies...

Andrew LDF 4-50A is rf transmission line that has copper plating over the aluminum center, skin effect there.

Sent from my SM-G781V using Tapatalk

 

[matthewsx]

I started as an audio engineer at 19 and have heard hundreds of audiophiles tell me about their $30k home systems. My response was always, do you have $30k ears to listen to it with? Also, really loved the guys who put tons of money into their car stereos, talk about a waste putting high end audio into the worst listening environment you have....

IMHO, building your own turntable would be a fun project but unlikely to provide much better sound than a "retail" unit. If you want to improve your listening experience invest into your listening room. Set your speakers at the proper distance from your chair and pay attention to the hard vs. soft surfaces in the room. I'm assuming you have a decent amp and speakers already so "tuning" the room is likely your best investment.

Either way, let us know how it works out and post some pictures....

John

 

[great white]

I started as an audio engineer at 19 and have heard hundreds of audiophiles tell me about their $30k home systems. My response was always, do you have $30k ears to listen to it with? Also, really loved the guys who put tons of money into their car stereos, talk about a waste putting high end audio into the worst listening environment you have....

IMHO, building your own turntable would be a fun project but unlikely to provide much better sound than a "retail" unit. If you want to improve your listening experience invest into your listening room. Set your speakers at the proper distance from your chair and pay attention to the hard vs. soft surfaces in the room. I'm assuming you have a decent amp and speakers already so "tuning" the room is likely your best investment.

Either way, let us know how it works out and post some pictures....

John

Sansui 8080db and quad AR4x speakers. I use either Sansui SS-35 headphones or a set of pioneer monitor 10’s when I want a more private listening experince.

I have a preference for the 70’s era Sansui stuff…Pioneer is a close second.

30 years if flying helo SAR has nuked my hearing. 2000hz is almost gone and over 5000hz I’m deaf. Still like my audio vintage and quality though. I tend to feel bass more than hear it. I can hear nothing and neither can the wife for bass, but I’ll “sense” it even a mile or two away…

 

[StevSmar]

I have ringing in my ears (Tinnitus) which sounds like static on an old TV, or thousands of crickets. Normally I don’t notice it, unless I’m thinking about it.

I really enjoyed hearing “high fidelity” music when I was younger and thought that with the ringing in my ears that I would not enjoy that aspect of recorded music again. That is until recently…, when I happened to play music from my phone in our vehicle- I was hearing things I didn’t know were present in the audio.

So I purchased a headphone amplifier and some reasonably good quality headphones- what a difference!!! The music now sounds “alive” (hard to explain).

The point being that even with the ringing in my ears, I can still hear details.

 

[C-Bag]

As an acoustic musician my ears have always been one of my prized possessions. Ive loved music since a small child and did my best to protect my hearing, For my favorite music the only time I used my turntable was to record to my BIC or Teac 2 speed cassette recorders or my Teac reel to reel. All three had no loss of highs and often in the case of the two cassette players had less hiss than the original vinyl. By the end of the 70’s vinyl was admittedly garbage with so much surface noise it drove me crazy. I personally was ecstatic when digital came along, if done right. I have my Technics direct drive turntable along with 3-400 albums in storage. I was a Dynaco man back in the 70’s and updated to Hafler pre and power amp through a set of ESS speakers. To my ear that combo sounds like I’m in the room with them. So yeah, to me vinyl and turntables are snake oil that I just don’t get. But to each their own.