I did my bit showing how to use 10 components in a 4-1 1-4 bridge. Seems too many folks don't get it. If you use only 4 components you get bad data if they all have the same distortion. It will have no output showing the distortion.
To calibrate the 10'er you can run it at V and V/2.
That was a bit I missed on the first go round. You can also move the components around in the bridge to verify if they all match.
The other advance is to match the values of the components to .1% and eliminate the need for a balance trim. That works great to check capacitors and reduces the FFT analyzer to only need 100 dB of range.
Don't know. Send me a bunch and we can add them one at a time until a difference is measured
Time to let out another secret of large scale sound systems!
In arenas they actually monitor carbon dioxide levels and adjust air intake fans to get the desired levels. Low for sporting events, left to drift higher during other events to keep the crowd less animated.
But it is easy to predict and measure dispersion in air! When you have dispersion you also have loss. In one particular stadium the loss at 200' and 20,000 hertz is 25 dB. Yes at that point there is easily measurable dispersion.
It is obviously (to some) not the monatomic gases. Also not really the carbon dioxide, but we could discuss the effect of humidity. Does this mean that a basketball arena has different properties than a hockey one? You bet it does. To compound the issue dual purpose arenas often put the basketball floor down over the ice.
Yes I seem to have been doing sound systems way too long to have this data. Also I seem to be the only one awake at this hour.
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Indeed, his involvement with secret government projects might have been in the field of psyops, rather than technology.
And there lies the danger for us! I am too, but earlier exploits scare the *rap out of me - looking back. Too many idiots on the roads today to even attempt many of those old exploits. I'll betcha that those red light cameras wouldn't catch any of these mighty beasts flying through an intersection at speed.
Hi Destroyer OS,
I'd also put a current engine into an old body style for day to day driving. 450 BHP today is a lot more controllable than it was when I was a lad. To get that same twitchy, nervous on-the-line stance in today's car might require a 650 BHP engine. Even then, it lacks that raw, barely in control application of power. Traction control, nice safety net that allows a young driver to reach truly destructive speeds without taking himself out getting there. So now he can take out a bunch of cars or pedestrians at the terminus of his journey. In the old days, guys like that usually put it sideways into something at lower speeds.
How fast did we go sometimes? One fella on a straight run drifted into a line of parking meters. He bent the first one over and that launched him into the side of a building about 15 ~ 20 feet up in the air. That goof survived in what was (compared to today) a heavy tank. Very impressive. Back seats went under the front seats. The drive shaft became a structural member holding the car in a "A" shape. Pretty unbelievable. That was into the second building from the meter. You really have to respect the amount of energy involved in high speed autos.
There was zero point in installing car stereos into these cars. You couldn't hear them with the engine running, even idling.
-Chris
That is a dream of mine.... a hot rod. Disc brakes and all modern under the hood. The ZZ Top song and video is great example. Listen at the intro when the Rod is stepped on... the sound of a perfectly tuned HiPO big block engine is music to my ears.
https://www.youtube.com/watch?v=Ae829mFAGGE
-RM
That's basically what I did with what for all intents and purposes was Yugo, an Italian design from the early 70-ies, with a brand new stregthened chassis, and the mechanics were true FIAT, but nothing like anyone ever put in a Yugo in any factory model. People call it a sleeper, but in reality it's much more than that, that vehicle is mental. A combination of old and new, carburrators gave way to an electrnic fuel injection, but God forbid witj any drive by wire solutions, strictly manual. The engine is a 1.6 litre FIAT OHC unit delivering 142 bhp at 6,800 rpm, warning limiting at 8,200 rpm and final limiting at 8,500 rpm. May not seem like much, but remember, the car weighs in at 820 kilos only, thus with an excellent power-to-weight ratio. It does 0-62 mph in 6.4 secn+onds, top speed has been measured at 211 km/h or 135 mph. Because it's small in proportion and light in weight, it is extraordinarily nimble and handles like a dream come true.
It is the horror of many a local wanna be speed kid, because it doesn't look like much but goes like stink and above all, its response to any command is literally immediate and very consistent. John should know a thing or two about that, he has a Porsche from those years. No ABS either, but I do have four oversized disc brakes all around, with power assistence, faciliitating excellent braking control from very little to very hard. It is in fact a tailor made car, crreated to my requirements. It just doesn't get any better than that.
And the look of other drivers' faces when I pass them is pricess. A Yugo? You gotta be kidding, what's that guy got under the hood?
It is the horror of many a local wanna be speed kid, because it doesn't look like much but goes like stink and above all, its response to any command is literally immediate and very consistent. John should know a thing or two about that, he has a Porsche from those years. No ABS either, but I do have four oversized disc brakes all around, with power assistence, faciliitating excellent braking control from very little to very hard. It is in fact a tailor made car, crreated to my requirements. It just doesn't get any better than that.
And the look of other drivers' faces when I pass them is pricess. A Yugo? You gotta be kidding, what's that guy got under the hood?
Car talk shorts this place out again for days.
Gas Monkey Garage: 1974 AMC Gremlin V8 Selling on eBay | eBay Motors Blog
The pictures to prove the ball joints were replaced had me LMAO.
Gas Monkey Garage: 1974 AMC Gremlin V8 Selling on eBay | eBay Motors Blog
The pictures to prove the ball joints were replaced had me LMAO.
If you were a chronic procrastinator like me the metal shards would foul the grease fittings so then it was only a matter of time.
I, like all you, am pursuing the best in clarity, intelligibility, and appreciation of microdynamics when listening to Click and Clack reruns.
That's what we're talking about, right?
The Magliozzi brothers good old MIT boys gave you a place to fix the exhaust leakage in your Corvair.
Anyone else here used turbo maps and area/radius of impeller wheel to size/select a turbocharger for a given engine displacement? And, then program the A/F curves for a two stage pump (engine + turbo)?
And computed/measured the required water/alcohol flow rate to be injected into the engine to keep head temps at optimum. Used exhaust gas thermocouples to measure exhaust temp at head port to aid in optimizing A/F ratio's?
Everything becomes non-linear and isn't simple to get it all correct for wide rpm range and loading. How much initial timing and how much to retard and when.. ignition. Static CR for high boost (>25psi manifold pressure) needed.
When to add in a seamless way, 150hp nitrous oxide into the engine for zero turbo lag. Ignition changes under nitrous? Radiator upgrade and clutch upgrades, stronger diff etc Staged enrichment injectors. Upgrade brakes and tires. Obtaining 500+ HP from 2.5 ltr engine that is street driven. Every bit as challenging as a phono preamp.
-RM
And computed/measured the required water/alcohol flow rate to be injected into the engine to keep head temps at optimum. Used exhaust gas thermocouples to measure exhaust temp at head port to aid in optimizing A/F ratio's?
Everything becomes non-linear and isn't simple to get it all correct for wide rpm range and loading. How much initial timing and how much to retard and when.. ignition. Static CR for high boost (>25psi manifold pressure) needed.
When to add in a seamless way, 150hp nitrous oxide into the engine for zero turbo lag. Ignition changes under nitrous? Radiator upgrade and clutch upgrades, stronger diff etc Staged enrichment injectors. Upgrade brakes and tires. Obtaining 500+ HP from 2.5 ltr engine that is street driven. Every bit as challenging as a phono preamp.
-RM
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No, what's your opinion of Thomas Keller vs Grant Achatz? You can't use Google that's cheating.
BTW I would actually like to talk about noise, dynamic range and trade offs between the two, etc. you know electronics. There are probably numerous fora frequented by the NASCAR crowd that would jerk back and forth to this car talk.
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Just why is it that some consider all this noise making to be pleasurable ???.
To me these noise makers represent the worst in terms of embedded energy, limited product lifetime, exhaust gas pollution, particulate pollution, consumables pollution (tyres, brakes, oils), the list is long.
Granted, up to date there has not been viable alternative to burning hydrocarbon fuels, but it seems that relatively soon we will view current vehicle technology as we view the likes of coal powered steam engines...ie noisy, polluting and just too environmentally costly dinosaurs/relics.
I chuckle when I see the likes of Jay Lenos Garage collections, sure these are collections of interesting engineering of the times, but in short order they will become worthless, useless, even outlawed relics of a past era, only allowed to be driven to events and exhibitions, and even then only using renewable fuels.
The future model of personal transport will be pooled, light weight efficient electric self driving situation aware autonomous vehicles, called up via a smartphone app or similar.
A major application will be delivery of foods and goods ordered online, thus reducing total energy requirements of the population.
The downside of this will be major increase in wireless communications to support vehicle networking and journey on the fly planning.
We will be bathing in even more man made EMR, with the associated concerns of high EMR exposure....I believe there is a solution to rendering these RF/MW transmissions harmless, even beneficial.
At present, electric vehicles merely shift exhaust emissions from the tail pipe to the local power station smoke stack, but in time renewable energy will provide all of this power.
The era of greenhouse gas emitting personal transport is soon over, with two countries already mandating electric only new vehicles by 2025 and 2030.
Dan.
I had to Google.....my GF is the best chef ever, all organic ingredients and love.
Yup, all this car talk is fundamentally boring, how fast, how powerful etc, BFD.
Go ahead Scott, noise is an interesting subject.
Here's another take - There are Three Kinds of Highway Noise Emissions: Lies, Damned Lies, and Averages
Dan.
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