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[Scott Holtzman]

I have been cleaning out my basement-and starting to throw away the old stuff I build decades ago.

I took a few photos before it went in the dumpster-but these were pulled out and went to the metal scrapyard.  Maybe some of it will end up in an amp in YOUR future

NO LAUGHING JR!!!!!!!!!!!!!!!!!!!!!!  All I had was simple tools and only my own experience to go on.

I used to collect sweep tubes out of TV's on the curb when I was a young teen and build 100W Linear Amplifiers for the CB crowd.  Sold them at the flea market.  Made good money at it to.  Kept a hi fi and a fast car habit going into college.

I thought that circuit design was a lost art but there seems to be a resurgence of microcontroller project boards. They have all sorts of A/D converters.  The kid I hired out of electronics school last year knew the difference between RS-232 and TTL voltages.  That and knowing the binder wrap colors on a 25 pair phone cable got him an instant job. 

Embedded software/hardware engineers are the highest paid in the industry and near impossible to find.

We had a lot of fun, but so does this generation. 

 What blows me away is the value.  If I recall a little 8 or 6 input allen and heath mixer was over a grand in the mid 70's

[Steve M Smith]

I used to collect sweep tubes out of TV's

I assume these are what we refer to as the line (horizontal) and frame (vertical) output valves. In the UK, this was usually a Mullard PL504.   I have heard the term sweep tube before but we don't use it here.

Luckily, when I was at high school and got interested in this stuff, I could get EL34s, EL84s and 6V6s fairly easily so I didn't have to re-purpose TV valves.

Later today, I'm going to try to get some pictures of an all valve/tube mixer I built for a friend a few years ago.


Steve.

[Jim McKeveny]

I assume these are what we refer to as the line (horizontal) and frame (vertical) output valves. In the UK, this was usually a Mullard PL504.   I have heard the term sweep tube before but we don't use it here.

Luckily, when I was at high school and got interested in this stuff, I could get EL34s, EL84s and 6V6s fairly easily so I didn't have to re-purpose TV valves.

Later today, I'm going to try to get some pictures of an all valve/tube mixer I built for a friend a few years ago.


Steve.

My dad had a repair manual for our 1962 Ford Falcon. The day I leaned how to calculate (pre-calculator BTW) volume of a cylinder in school, I raced home and flipped to the page that displayed Bore and Stroke.

I checked my math again and again. "Ford wouldn"t be wrong! They're not kids like me!"

I was sadly disappointed when our advertised 144 cu. in. car really turned out to be 142 and change...

Years later, when I purchased a calculator with, OMG! exponential function, I traced coordinates for a horn flare on graph paper. I didn't match what I saw on commercial horns. WTF??

[DAVID J. SYRKO]

If you had a Tapco 6 channel mixer with ALtec A7s-you had hit the big time.

Add in a Crown DC300 and WOW-you were cool. 

Oh how times have changed.

Now any idiot with a couple of bucks can buy a system that makes a lot of noise-but that is about it-noise.  Not quality sound.

While the gear had gotten much better-I don't feel that the "average" sound quality is any better-in fact I think it is worse-since it is so easy for people to get into the business.  At least years ago it took a decent amount of money to get a sound system. 

That weeded out some of the people

When I got out of Tech school I worked for an AV company that put on shows for clients to introduce their products.  The guys that were putting together the amp racks used the DC amps.  They said they would have to fabricate a bracket to support the transformers in the rack because the transformers would snap off of the amp during transport.  I also noticed  when you would push the amp the front lights would dim.

[Stephen Kirby]

Poverty is the mother of invention.  Does anyone remember Tiger amps?  Around 80W SS thing you got plans for and parts from Allied or Heath.  Build a couple cabinets with some sort of horn flare and power with one or two of these and rock the gym.  In the early '70s Acoustic came out with a cabinet that had a stack of 6x9 car speakers playing into a plastic flare.  A buddy copied these but made the flare with 1/4" ply and they sounded much better.

Some folks here may remember the small "line-arrays" I built 6-7 years ago based on planar tweeters.  Those are long gone but there's still room for money saving experimentation.  I still have the neo 8's from those and my next project is to figure out what sort of dome tweeter is in the AccuGroove cabinets (I think they're Audax units) and build some small bar band wedges.  These days you can get a plate amp with DSP, hook it up to a computer, run Smaart on your deck and tune the DSP to pretty good effect.

The concept behind those wedges is that in bars and other situations where you're right on top of the monitor, the intelligibility isn't very good.  Even if you get the angle so it's pointed straight up at the singer.  I've been doing some gigs lately as a drummer and notice that I can hear the monitors pretty clearly from further back.  Having heard the AccuGroove cabs from on stage I get their assertion that horn loaded treble units have more throw but are less good in the nearfield.  It makes sense to me that the same thing happens when the singer is right on top of a wedge.  Another garage project at least.

[Ivan Beaver]

Poverty is the mother of invention.  Does anyone remember Tiger amps?  Around 80W SS thing you got plans for and parts from Allied or Heath. 

The "real guys" built THIS.  It had "all the power you need to fill a stadium with sound"

http://www.tigersthatroar.com/?page_id=59

[Chris Hindle]

The "real guys" built THIS.  It had "all the power you need to fill a stadium with sound"

http://www.tigersthatroar.com/?page_id=59

Nice one Ivan. I remember building a couple of the Dynaco kits. Wern't they around 400W a side ??
A lot of things are a bit foggy about "those days" Used them on home-built A-7's
Chris.
 

[Scott Holtzman]

Nice one Ivan. I remember building a couple of the Dynaco kits. Wern't they around 400W a side ??
A lot of things are a bit foggy about "those days" Used them on home-built A-7's
Chris.

SWTP was a big player in early computer kits too

[Ivan Beaver]

SWTP was a big player in early computer kits too

I have one of their old catalogs.

Their "BIG DADDY" was something like 64K.  I need to find it and look it up.

Oh how times have changed

[duane massey]

Built several Dynacos and Tigers. Like some of us, they were a stepping stone to bigger things.