Vintage Electronics – Schematics and Suppliers

Vintage Electronics – the road left behind

I always envy people whom spend thousands of dollars on high end audio equipment in search as always for the best sound. Nowadays there’s a trend towards vintage audio. I do not know what drives this because it encompasses valve/tubes, semiconductors and always analogue, really old stuff. Nostalgia plays a big role. It has to, modern semiconductor amplifiers are far superior in reproduction quality to their older brethren. Vintage equipment had one vital difference, there was never any skimping on hardware – solid construction, over-rated power supplies and enormous cooling. (mostly).

vintage electronics
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I have heard bad things about class-D audio. I have heard exceptional things about class A audio. I believe SET (single ended triode) and OTL (transformerless tube) amplifiers are the best. I’m from old school – hype is a mysterious thing and we will remain like the mythical Lemming. My personal experience is that SET and OTL are hype, I have heard class A with exceptional quality and of course class A which sounded downright dodgy. We put it down to the output transformer, the transistors used, Chinese tubes, Silicon diodes and of course the magical speaker wire and even power cables.

Vintage Electronics Power versus modern speaker drivers with cones made from concrete

Here’s the thing though… as amplifiers (audio) go up in power the loudspeaker has become less efficient. Years back one could be reprimanded for pushing against the paper cone of a loudspeaker. Nowadays you can take a sledgehammer against the cone and it will hardly budge. Car audio must be the worst. Learn about SPL. Personally, I often wonder whether the SPL ratings as advertised are that accurate. Kapton voice coils, liquid cooling and gigaflux capacitors. Here, you pay for what you get. I have used two cheap 15″ bass drivers on a pro-audio amplifier and did a comparison with a much more expensive albeit 18″ pair of woofers and the pressure level difference measured at 200W RMS per channel was like night and day. (same program material). Modern materials has allowed much more powerful loudspeakers to be manufactured and in my opinion some of the better known brands can handle way in excess of double their power rating without failing. (do not try this at home).

Turntables – turning rumble into music

Having a great turntable on display, especially an expensive one, always enhances the snob value of your home equipment. I have one argument though – where the hell are those linear trackers? I did some research on turntables and unless you are specifically looking for a linear tracking TT you will find most audio equipment using conventional turntables. Many enthusiasts in fact don’t like linear tracking which I find strange. For more details on turntables go here… If you are really interested in getting yourself a top-notch turntable have a look at the images under Google and make your own. Maybe even buy one, direct drive or belt is the best and then apply the modifications. Garrard used to make quite good turntables at a very affordable price – unfortunately most of the turntables I either owned or came across in the Garrard line were ones with idlers. I used to DJ in the 80s and used two PS-X7 (Sony) – they were direct drives. Extremely reliable. Gave them away. Pity!

Best Buy on eBay or Vintage Electronics at a Price

The best way to do research on vintage equipment is through eBay. See a well known model, do a specification search, do another model, spec search etc. I have done this numerous times and the one thing that always stood out – modern audio from a well known manufacturer always works out cheaper. Modern home theater audio amplifiers lack the robustness of the older generation stereo units especially regarding the mains or power transformer’s load handling capabilities. It is after all the most expensive part in the chain.

Reel to Reel – But Tascam can be cheaper

Reel to reel and cassette recorders offer you the biggest challenge when purchasing without opening and testing. Idlers, belts and switches eventually give up the ghost. Front panels are difficult to restore unless you do it through a professional service. The sad part is that unless you are recording at very high tape speeds they just do not compare to a digital device with built in analogue converters or DSP. Even the more expensive RTR and cassette decks have atrocious signal to noise ratio. Often they require recapping and once this is all done and dusted you then need to find a supplier of good audio tape. Before rushing out please do some homework – classy audio tape is expensive. Can the bias handle the tape type? RTRs look really great but only have nostalgic value unless you go the whole hog and get a reputed professional unit. I think a Tascam MTR looks much better and of course, works better as well.  Have a 1947-48 Chicago wire recorder at home – any offers?

Vintage Electronics: Where to go, where to go?

Of course, eBay is a fine way to start. Know your seller and make sure you have a solid returns policy in place. Overseas shipping is always a problem, especially if you have to return it, usually at your cost.

Schematics:-

To sum up, unless you are really prepared to buy old vintage electronics understand the reason why first. Nostalgia does play a role and there is nothing wrong with this but going high end is going to see you grossly out of pocket for possibly mediocre returns. You may be shocked to find that your vinyl collection was a local and very inferior press. Buy the best program material. Your European copy may sound very different to the one purchased in Africa.

And yes, I just love big VU meters. Maybe that’s what makes vintage electronics that much more better looking!

Guitar Effects, stompboxes – suppliers

stompbox - the incredible GT-100 from BOSS

Stompboxes – Guitar Effects

This article is based on my own research on the web and snippets of building my own projects. Separating facts from opinions can be quite a challenge but one thing is definite, there’s lots of information on the net, lots of schematics, tons of opinions and buying the real McCoy is often cheaper than making your own.

Cautionary Note: Effects pedals do need to comply to FCC regulations pertaining to radiation. Read here. FCC case against EHX here. In the forums I read this covers digital equipment. I do not have the facts before me but an astable multivibrator running above 9kHz may be constituted as digital although it is used in an analogue circuit.

stompboxes - the incredible GT-100 from BOSS
Flagship stompbox from Roland, the GT100

For those new to stomp boxes and electronics in general I do recommend this web site DIYstompboxes….

Before you even embark on a stomp box or effects pedal project ensure that you have a local supplier of aluminum (aluminium) die-cast or sheet metal boxes which will withstand abuse. Yes, you will stand on it and yes, they do get thrown around. Having said that, if you know a machinist or metal worker with a sheet bender, all the better.

My own opinion is that in many listening tests the older analog effects pedals sound cleaner than digital – it is an opinion though. Digital electronics has made capturing the settings for a multitude of effects a breeze, even including analog sounds. See cautionary note above.

Snob Value on Stompboxes

Snob value climbs into almost every forum – do not be afraid to say that you have a cheap pedal, it’s about you and not them. Each person to their own style. Hearing is like a fingerprint – what sounds you hear may not necessarily be what the other hears. (or perceives to hear). Our hearing is all different. Blind listening tests have blown many an ego apart.

There has been a lot said about germanium transistors and diodes (germanium semiconductors in general) used in older pedals. Their switch-on parameters are different to silicon, they switch-on at a lower voltage (0.2V to 0.3V unlike silicon’s 06V to 0.7V), they are not cheap and they do not like heat. The die hards of audio prefer them for their soft switch on characteristics, again the great semiconductor vs triode and pentode debacle. The truth is, they do sound different. We’ll find a way around this later.

BOSS DS-2

stompbox - the BOSS DS-2
BOSS DS-2

Cost of making versus buying the ready made product. In Cape Town, South Africa my build of the famous BOSS DS-2 cost me close to 100 U$ compared to the locally available unit for 95 U$. Making a one-off circuit is always more expensive than mass production. I could have got an equivalent Joyo for 60 U$ locally. The big difference is in the enjoyment of after build modifications. The circuit is fairly comprehensive. I do believe it to be an infringement of copyright so will not post any details here suffice to say I doubt I would do it again.

The Free Information Society has a wonderful selection of schematics under Schematic Archive (right hand side menu).

Thinking local: South African website by Benjamin Craig selling under the name of Craig: Craigamps – interview with Benjamin Craig, Doughnut Magazine – nice read and insightful for those wanting to build their own stuff.

So you decided to build your own against all advice and now run into a small problem – where to get a germanium diode? On my side of the world a small signal diode cost 1.40 U$ but I urge you to read this very well written article on Germanium Vs Schottky diodes on the Rezzonics website.

Stompboxes – Building your own…

The reality is people want to build their own. The reality is that there are suppliers and if you know what you want there are even kits out there. Here are some of the better known, although maybe outside your country or region you can get a general idea as to what is outside there, pricing and of course – knowledge on the products. If anyone wants to add stores to this list please contact us at parts-ring.

Stompboxes on You Tube

Almost 9 times out of ten the sound that you want through a listening test will be available to you on You Tube. There are comparison tests and there are stand offs. I have come across some engineers whom are totally biased because they work for the company doing the marketing of that particular product and then of course you get the muso – sometimes even more biased. Do the rounds, listen to the different pedals, synths, whatever but also note that certain amplifiers also sound different. They are designed to sound different. Trying to get that Knopfler or Gilmour sound is never easy – they have their systems often re-engineered to sound different. This is not a cheap exercise but this is where your expertise as a DIYer comes in. If you are working on battery powered equipment the permutations to circuitry is endless and you won’t get electrocuted. Don’t try this with valve gear though.

Although copyrighting of schematics must be a very difficult and expensive exercise there are copyrights on certain material so be cautious. BOSS which is part of the Roland company I am sure will not be happy to hear you have been infringing their patents and selling off cheaply. Reverse engineering products nowadays with laser and 3D printers is a very common practice and should not be encouraged but such is the way of the human, if it can be done it will be done.

The three major websites which have really great reviews and product documentation is Sweetwater.com, SoundonSound.com and Musiciansfriend.com. You Tube will have whatever product you want to listen to reviewed and tested to the hilt, somewhere. Germanium diodes can be obtained for a cheaper price elsewhere but do try Schottky and LED technology. If you do need germanium try to buy in bulk to get discount. They can always be used elsewhere in any event – they haven’t disappeared entirely.

The conclusion – Glenn DeLaune on David Gilmour

Because I am a Gilmour (and Waters) fanatic I had to conclude with the great sound of Pink Floyd on one of the highest ranked stompboxes of all time, the BOSS GT-100. Glenn is pretty phenomenal too!

https://www.youtube.com/watch?v=jccogK_–GU