Dedicated Stereo/Audio/Video thread

[John Kemker]

It has recently been announced that Schiit Audio (http://www.schiit.com) has discontinued the Sol turntable, of which I own one. They will honor the 5 year warranty, but will manufacture no more parts or support it after that.

 

[Hobie1dog]

it's a really simple turntable so there shouldn't be anything going wrong with it, but I would get any spare parts that you think you may need.

 

[John Kemker]

Definitely planning on buying a spare tonearm or two.

 

[FredA]

Definitely planning on buying a spare tonearm or two.

Do they go bad or something?

 

[tsmith1315]

It's a good looking turntable. You might want to price a spare motor. I have an old AR XA and AFAIK, there's only one source left for a direct replacement.

 

[Sandy H.]

And. . . if you buy a spare or two today and sit on it for 5-10 years, but don't need it, you might break-even/beat inflation. I bet a lot of people wish they were sitting on authentic/vintage transistors. . .not sure if a motor or tonearm would appreciate like the OOP active components, though.

Sandy

 

[tsmith1315]

I bet a lot of people wish they were sitting on authentic/vintage transistors.

Sandy

Yeah, I wish I had a stock of old Toshiba JFETs or Hitachi lateral MOSFETs right about now.

 

[OverTheTop]

We have an ICP spectrometer that makes a plasma about the size of your thumb with 1.5kW of RF power and is about twice the surface temperature of the sun. We had to do a control loop analysis on this and the normal way is to add some modulation and sweep the frequency while measuring the relevant parameters. We had it set to sweep from 1Hz to 50kHz with quite a low modulation depth and started it off. By the time it got to around 8kHz you could barely stand to be in the room and I hit the e-stop (pulled the cord from the wall) at around 12kHz. It was sounding like a jet engine spooling up. People came running from the other building to see what was going on. Seriously loud. I would not have believed it if I had not heard and seen it myself.

Because plasma is such a good transducer I had always thought it would be cool to have it say "extinguishing plamsa", using a speech synthesiser, when you turn the plasma off during normal instrument operation.

 

[Sandy H.]

Yeah, I wish I had a stock of old Toshiba JFETs or Hitachi lateral MOSFETs right about now.

I bought a bunch of 2SK170's and 389's (I think those are the right numbers, but don't hold me to it) in the late 90's when I first got into DIY. I say a bunch - probably about 20-30 of each. I assumed I'd have to spend a bunch of time matching and wanted to get perfect sound. This was for a Pearl Phono before there was a Pearl 2. . .

Anyway, never built it and around the time COVID shut everyone down, I decided to build the Pearl, but wasn't sure what to do about not having the transistors. I found that there were some options, but when pulling out my box of parts, I found the transistors. I think I paid about $1 ea and there have been people paying $10-20 each for real parts in recent history.

I built a matching rig and sure enough they were all legit (before the counterfeiting of those parts became common) and they were pretty well matched over the whole batch.

Still haven't finished the Pearl, due to a FUBAR on my case sizing, but I've got them all labelled and an excel sheet telling me which ones to use when I eventually finish it out.

Sandy.

 

[Sandy H.]

[snip]
Because plasma is such a good transducer I had always thought it would be cool to have it say "extinguishing plamsa", using a speech synthesiser, when you turn the plasma off during normal instrument operation.
[/snip]

That would be extremely awesome. Maybe also make it say "I'm sorry, Dave, I can't do that" if something was set inappropriately.

Sandy.

 

[OverTheTop]

I bought a bunch of 2SK170's and 389's

I have an amp I built back in the 80's that uses those. Flat (within 1dB) from 7Hz to 100kHz IIRC. Less than 0.003% THD at full power @10kHz I think. Very clean amp.

I might dig it out and post a pic.

 

[Hobie1dog]

 

[tsmith1315]

I bought a bunch of 2SK170's and 389's (I think those are the right numbers, but don't hold me to it) in the late 90's when I first got into DIY. I say a bunch - probably about 20-30 of each. I assumed I'd have to spend a bunch of time matching and wanted to get perfect sound. This was for a Pearl Phono before there was a Pearl 2. . .

Anyway, never built it and around the time COVID shut everyone down, I decided to build the Pearl, but wasn't sure what to do about not having the transistors. I found that there were some options, but when pulling out my box of parts, I found the transistors. I think I paid about $1 ea and there have been people paying $10-20 each for real parts in recent history.

I built a matching rig and sure enough they were all legit (before the counterfeiting of those parts became common) and they were pretty well matched over the whole batch.

Still haven't finished the Pearl, due to a FUBAR on my case sizing, but I've got them all labelled and an excel sheet telling me which ones to use when I eventually finish it out.

Sandy.

Cool! Be sure to post some pics when done.

2sk389 is the dual version of the 2sk170's. Good thing you found yours! I have a couple 2sk170/2SJ74 pairs, intended for an M2x build whose PC boards and input stage transformers were tossed out in a cleaning session while I was having surgery. Linear Systems still makes them in batches, but they're about the same price as the old Toshibas. Given the prices, I'd call 20-30 a bunch, too!

I have an amp I built back in the 80's that uses those. Flat (within 1dB) from 7Hz to 100kHz IIRC. Less than 0.003% THD at full power @10kHz I think. Very clean amp.

I might dig it out and post a pic.

You're not waiting on us, are you?

 

[Hobie1dog]

 

[John Kemker]

It's not that the tonearms are particularly fragile. It's that you can mount other cartridges on them and swap them out very easily.

And, the wiring harness for the cartridge can be a bit fragile, so spares are nice.

Belts. I need to find out about spare belts. On my to-do list.

 

[Sandy H.]

I wonder if using a vacuum sealer and/or refrigeration would help with belt life. Oh wait. . . this is the rocket forum, not the audio forum. . . must talk about glue. . . .but then again, I wonder if using a vacuum sealer and/or refrigeration would help with belt life. Dang it!!!!

All meant in jest. The obsessions we have make us who we are. (Don't even look at my posts on the lawn sprinkler forum. NSFW. . . )

But in all seriousness, what is the best way to store a belt for years/decades? Not joking this time. They have to dry out or oxidize. I know woodworking tools are often stored in vacuum bags and metal shop stuff is often stored covered in oil and/or a tar-like substance. From work experience with hydraulics you either store seals in the type of oil to be used or in a ziploc bag. Parker asks for the date code every time you ask for a replacement/warranty. . .

Sandy.

 

[FredA]

Anybody vacuum your turntable mat to make it sound better?
Or own[ed] a Tice Clock?

 

[tsmith1315]

Or a ground box?

 

[Woody's Workshop]

If anyone has an Altec Lansing ADA-305 Speaker System that is in working condition and would like to sell it, send me a PM.

 

[boomtube-mk2]

So how many of you are thinking that the one on the left would make for a good start on a scale model of an "Orion"* spacecraft?

*Wiki: "Orion Nuclear Spacecraft".

 

[Hobie1dog]

Anybody vacuum your turntable mat to make it sound better?
Or own[ed] a Tice Clock?

No, but that reminded me to take my rubber stock mat off my Revox TT and clean it really good.
Thanks.

If anyone has an Altec Lansing ADA-305 Speaker System that is in working condition and would like to sell it, send me a PM.

The small computer system?

 

[Woody's Workshop]

The small computer system?
No, Speaker System. Has a Sub Woofer & 2 Sats. w/High & Mid Speakers in both.
Works off any speaker Jack for 3 lines, or any USB. Not wireless, it's too old.
Has 2 modes, Surround Sound and Stereo.
I have the original install CD so I also have all the sound effects.
Mine works fine, but I need one to hook up to the TV.

 

[Hobie1dog]

sorry I left out "speaker" system and yes I was talking about the small speaker system for the computer

 

[OverTheTop]

Pulled the old amp out to get some pics for this thread. Specs were not quite as good as I had remembered on an earlier thread, but still exceptionally good.






I remember I had to fix a blown FET and never got around to getting the cable ties back onto the wiring. I also lost the aluminium extrusions that hold the top cover in place, during a house move.

 

[tsmith1315]

Pulled the old amp out to get some pics for this thread

Cool, thanks! Those Hitachi lateral MOSFETs have been hard to find for a long time. I'd like to have several pair of them for a couple of old projects.

And dual mono... is that a Borbely Servo 100?

 

[OverTheTop]

And dual mono... is that a Borbely Servo 100?

No. Homebuilt, Electronics Today International magazine, Series 5000, circa early '80s.
Here are some more details on it:
https://www.stereonet.com/forums/topic/255837-series-5000-mosfet-stereo-power-amplifier-upgrades/
I have the preamplifier around somewhere also.

 

[tsmith1315]

Electronics Today International magazine, Series 5000, circa early '80s.

Neat, I love to see homebuilt stuff! Please post the preamp, too, if you run across it!

The Borbely Servo 100 and DC 100 amps were also homebuilt, published for DIY in Audio Amateur magazine, and similar age. PCB's and kits were sold through Old Colony Sound Labs here in the US. I don't recall the layout, but the output transistor compliment was the same as the Series 5000, and I'm pretty sure the supply voltage was the same.

 

[EPflyer]

There is a lot of cool equipment here. I have a turntable that I purchased in 1978. It is a Pioneer PL-570. It is full auto with direct drive. I am happy to say that it still works great. The cartridge is a Grado G1+ also from '78.
The album is All things must pass 50th anniversary edition. Just released last week.

 

[John Kemker]

It's not that the tonearms are particularly fragile. It's that you can mount other cartridges on them and swap them out very easily.

And, the wiring harness for the cartridge can be a bit fragile, so spares are nice.

Belts. I need to find out about spare belts. On my to-do list.

So, I got a response from Schiit:

Tonearms seem to be the problem with manufacturing them. They're a carbon-fiber tube with some other stuff added. I wonder....

The spares I can buy:
Set of 2 belts for $3.00
Platter: $30.00
Grease: $2.00
(all plus the cost of shipping)

Now, who do I know makes carbon-fiber tubes? Hmmm....

 

[Hobie1dog]