TYPES OF LOUDSEAKERS

[LVMAN777 352]

"... You've got three choices for speakers.

 

The cheapest speakers are made with cone drivers. 

  You pump electric current through a wire coil. You stick that coil inside a permanent magnet. Thanks to Maxwell's equations, there is an "e cross B" force that causes the coil to move in time to the music. This would be fabulous if the coil could move air. It seems that sound is a variation in air pressure and a coil doesn't make too many waves. So you glue a paper cone to the coil and then hope that the paper cone picks up the coil's motion. Well, it sort of does. Sometimes.

 

You can lay down a big string of magnets and then stretch the coil in a big long ribbon in between them.

Then you truly can use the current-carrying conductor as the sound radiator. These are called ribbon speakers. They tend to perform better, especially at high frequencies, than cone speakers. However, the moving parts of these speakers always end up being much heavier than the (mylar electrostatic speaker). Heavier implies more inertia which interferes with accurate tracking of the musical signal.

 

 The final option is...called an electrostatic speaker.

If you think back to freshman physics, you can probably remember that an infinite plate of charge create an electric field that is uniform everywhere. If you have another parallel infinite plate, oppositely charged, you get a gap where the electric field is perfectly uniform and then no charge anywhere else. This is how a capacitor is constructed. You just apply a voltage across the plates and it results in an electric field within.

...we...use Mylar...and sprayed-on aluminum.... The output of the amplifier can be transformed up to about 30,000 volts peak to peak and the Mylar can be charged up to a 10,000 volt "bias voltage." Now you have the Mylar really flapping back and forth in between the plates but it still won't generate any room sound until you punch holes in the plates to let the air out/in. This violates our "infinite parallel plate of charge" model but only when the music is very loud, i.e., when the Mylar is almost touching the plates.

The problem with electrostats is that the Mylar doesn't move very far. They don't have the excursion of cone speakers. So they have to be big. Very big if you want to play music at concert hall volumes. And a fundamental law of acoustics is that a driver that is large relative to the wavelength it is radiating will beam. The wavelength of a 20 KHz tone is about one inch. That means that a big flat electrostatic speaker will sound great if it is pointing at you but if you are off-axis you'll lose the high frequencies.

There are two ways of solving this problem. One is the brute-force American way. You just curve the plates and the diaphragm. Then the wavefront launched by the electrostat mimics that of a line source. So you get all the horizontal dispersion you need. You still have to make the things really tall because there will be no vertical dispersion..."

 

http://philip.greenspun.com/materialism/stereo 

[kve777 6,888]

Cone drivers are not always cheap, take the OHM F with it's very precise cone Walsh driver:

[loner_t 2,568]

Kevin... are these Ohm F the ones where you delivered some equipment?

 

And these ? 

 

 

[Balok 1,667]

I thought this thread was about people sea(e)king loudness. 

[LVMAN777 352]

 

Lincoln Walsh died a year before his radically innovative speaker technology made its commercial debut in the Ohm Acoustics F in 1972. The speaker featured an omnidirectional Walsh driver that projected a massive stereo soundstage. At the time of its introduction the $900 per pair Ohm F was hailed as one of the greatest speakers of all time by the international press. It sounded like nothing else, and the single 12-inch, truncated cone driver produced bass, midrange and treble frequencies (37Hz to 17kHz). The driver had a titanium top section, aluminum midband and paper bottom, with a single voice-coil at the top of the driver. Even today, bona-fide full-frequency drivers like that are rare. The Ohm drivers and cabinets were made in Brooklyn.

According to Ohm's President John Strohbeen, the early production Fs had "functionality issues." "They needed 300 watts to get going, and 301 to blow them up," Strohbeen said with a chuckle.  the F remained in production for 12 years, until 1984...

the price had more than quadrupled to $3,995 per pair!.."

 

(CARVER AMAZING LOUDSPEAKERS  WERE ONLY $2,195 OAK $2,495 Piano Black in 1990 back when I bought a set in Piano Black...new..

 

.and a NEW Carver Receiver MXR-130..

 

  "...the Carver Receiver was introduced in 1984...

 

combined the key technologies of two earlier Carver products...

 

...the Asymmetrical Charge Couple Detector design derived from from the TX-11 tuner...

...the Magnetic Field Amplifier first shown in the Carver M-400...

The original list price for this unit was $699.

...The Carver Receiver is one beast of a receiver.

Output at clipping tested at

 176 watts/channel at 8 ohms...

264 watts per channel at 4 ohms...

313 watts per channel into a 2 ohm load...."

 

 

 http://www.audioasylum.com/cgi/t.mpl?f=vintage&m=49662

 

 

http://www.cnet.com/news/forty-years-ago-the-ohm-f-speaker-was-a-game-changer-it-still-is/

 

 

[PMAT 2,040]

I would love to hear those Ohm Walsh speakers.

[UncleMeat 1,173]

What's strange about them is that the cone vibrates like a ribbon (or like linaeum tweeters), not linear displacement along it's axis. The result is as much off-axis sound as sound firing forward, the truest form of a point-source sound wave. I'd really like to hear them also; I saw a pair on CL few months back and should have bought them.

[LVMAN777 352]

MY OHM F'S ...purchased NEW IN 1974 when I was in the US Air Force cost $900 a pair...

SOLD THEM in 1978 after I got out...$450...4x365= 1460 days....31 cents a day

 

"...According to Ohm's President John Strohbeen, the 

 

early production Fs had "functionality issues."

 

"They needed 300 watts to get going, and 301 to blow them up," Strohbeen said with a chuckle.

 

Ohm couldn't repair them, so they replaced broken drivers under warranty.

 

(until the warranty ran out)

 

The engineers kept redesigning the driver to improve reliability,

 

but it was the introduction of ferrofluid-cooled voice coils that cured the F's reliability woes..."

 

 

http://www.cnet.com/news/forty-years-ago-the-ohm-f-speaker-was-a-game-changer-it-still-is/ 

 

BOUGHT NEW CARVER PLATINUM"S around 1988...around $2,200 

[loner_t 2,568]

If they were easy to ship, we could collectively buy the 1800 pair and put on a road show but shipping will be a PITA.

[dr_gallup 42]

I heard the Ohm F speakers back in the late 70's driven by some Citation amps.  I loved them but as a student they were out of my price range, particularly since they need a pricey high power amp.  Very cool design.

[LVMAN777 352]

I heard the Ohm F speakers back in the late 70's driven by some Citation amps.  I loved them but as a student they were out of my price range, particularly since they need a pricey high power amp.  Very cool design.

 

In 1973 I joined the US Air Force... and sold my Honda 750K2

IN 1974 I BOUGHT A NEW STEREO....and had it shipped to my room in Cheyenne,Wyoming 

 

OHM F SPEAKERS...........$900

PHASE LINEAR 4000.......$600

PHASE LINEAR  400........$500 

THORENS TD-160C..........$300

SHURE V15-3......................$50.

                                          --------

                                          $2,350 

[zumbini 6,147]

 

 

 

I heard the Ohm F speakers back in the late 70's driven by some Citation amps.  I loved them but as a student they were out of my price range, particularly since they need a pricey high power amp.  Very cool design.

 

In 1973 I joined the US Air Force... and sold my Honda 750K2

IN 1974 I BOUGHT A NEW STEREO....and had it shipped to my room in Cheyenne,Wyoming 

 

OHM F SPEAKERS...........$900

PHASE LINEAR 4000.......$600

PHASE LINEAR  400........$500 

THORENS TD-160C..........$300

SHURE V15-3......................$50.

                                          --------

                                          $2,350 

 

BX/PX pricing was awesome. I was stationed at a remote site (Camp Mercury, NV) but it was only 80 miles to Nellis AFB.

[BillWojo 542]

Zumbini, PX pricing was awesome although I never was in the military. I used to go out to the Fort Dix base with a friend of mine who was a Major in the Airforce. At the time I wasn't into stereo gear but stuff was heavily discounted. My friend George was a Carver salesman at the base when he purchased a lot of this gear. He was able to purchase the Amazings for even way less. After you were a salesman for Carver a certain period of time, you could purchase ONE piece of Carver gear for the factory cost. Of course George made the correct decision and purchased the most expensive piece they made. LOL He told me that he was going to buy the Silvers but when he was on the phone with Carver he decided right than and there to go for the Plats. He didn't want to spend the rest of his life wondering how much better sounding the Plats would have been. Even than it was a lot of money for a normal working guy.

Back in the day you had to be a serious audio guy or be pretty loaded to buy this stuff.  

 

BillWojo

[LVMAN777 352]

When I first moved to Las Vegas I lived two blocks from the Nellis AFB Main Gate on Craig Road..

I go to the new Va Hospital now....the Px prices are higher than Fry's or Newegg or Amazon..or Walmart

I used to sell HDTV's...

You can beat the PX prices now at any discount store...times have changed. 

[UncleMeat 1,173]

 

 

You can beat the PX prices now at any discount store...times have changed. 

 

That's because nothing is made here anymore; Walmart is China's "PX"

[dr_gallup 42]

 

 

 

I heard the Ohm F speakers back in the late 70's driven by some Citation amps.  I loved them but as a student they were out of my price range, particularly since they need a pricey high power amp.  Very cool design.

 

In 1973 I joined the US Air Force... and sold my Honda 750K2

IN 1974 I BOUGHT A NEW STEREO....and had it shipped to my room in Cheyenne,Wyoming 

 

OHM F SPEAKERS...........$900

PHASE LINEAR 4000.......$600

PHASE LINEAR  400........$500 

THORENS TD-160C..........$300

SHURE V15-3......................$50.

                                          --------

                                          $2,350 

 

Even at that pricing Ohm F's were out of my budget.  I spent ~$400 on my complete system in 1975, that was before I heard the Ohm speakers.  Even when I got out of collage and had a real job my next pair of speakers cost less than $900.  I had cars & motorcycles to buy too.

[UncleMeat 1,173]

In 1974 couldn't you buy a new car for $3500+tax? That would mean that the price of a $2350 stereo would be an equivalent cost of about 25,000 today.

[LVMAN777 352]

In 1971 I bought a NEW Chevy Camaro for $3,000 cash in LA...and got a $300 rebate check back from Chevy..

MY 1972 Honda 750K2 was about $2,000 NEW in LA

My 1974 Moto-Guzzi 850T "Interceptor" Motorcycle was $3,000 NEW in Denver, Co.

 

 

 

 

 

 

 

[UncleMeat 1,173]

That's telling, it sounds like people actually had cash in their pockets back then, not just credit and debt due to inflation. Not very many middle class people can walk in to an auto dealership and pay cash for a new car today. I like how the auto industry masks the inflation by 'offering' low finance rates and price rebates (like they are trying to give you a deal).

 

1974 Inflation continues to spiral out of control around the world reaching 11.3% in the USA and 17.2% in the UK and the global recession deepens. The famous skeleton "Lucy" is discovered in Ethiopia which lived between 3.9 to 3 million years ago. More and more smaller digital based consumer products appear in the shops and the earliest forms of Word Processors appear which resemble a typewriter more than a computer. After the findings of the Watergate Scandal Richard Nixon becomes the first US president forced to resign from office.

Cost of Living 1974

How Much things cost in 1974 Yearly Inflation Rate USA 11.3% Yearly Inflation Rate UK 17.2% Year End Close Dow Jones Industrial Average 616 Average Cost of new house $34,900.00 Below are some Prices for UK guides in Pounds Sterling Average House Price 10,990 Gallon of Petrol 0.42

A few More Examples Cost of a gallon of Gas 55 cents Average cost new car$3,750.00 Samsonite Case $62.00 Average Income per year $13,900.00 Average Monthly Rent $185.00

 

[PDR 1,194]

I remember a lot of people walking around with cash in the late 70s and 80s.

Interest rates were so high here then....who would take a loan for anything at 12%?

I bought my first house from a guy for 1 dollar in 1983, the rates were 11% and he

just couldnt afford the $700 a month.....I just assumed the mortgage.

It seemed like a good deal at the time.....a few years earlier rates hovered around 20% 

[LVMAN777 352]

In 1974-1975 I made  $400 a MONTH....(less than $5,000 A YEAR)....workin for my "UNCLE SAM"....USAF

 

But Free room and board....

 

Used the Base Credit Union in 1974 to finance the Moto-Guzzi... 

[UncleMeat 1,173]

It's only gotten worse; that was interest-based inflation and those that chose to utilize credit had it tough (like to buy a home or car you had not saved for), but today we have monetary inflation (devaluation of the dollar) that puts everyone behind the eight-ball, for every purchase.  Look at this graph; it all started in the early 70's.

 

 

 

 

Lots of Inflation, Not So Many New Jobs - Source Here

This chart compares the percentage change in non-farm payrolls with the percentage change in the consumer price index starting in January of 1939. The two track closely together for over 30 years, until they begin to significantly diverge around 1970. This coincides with the collapse of the Bretton Woods Accord in 1971 and the move to a floating currency exchange system.

Data Sources: Bureau of Labor Statistics

 

THANKS GLOBALIZATION!

[helicopter pilot doug 110]

The chart above clearly shows "Nixon's Colossal Monetary Error: The Verdict 40 Years Later"

 

Back to the original topic and the OHM speakers.  If you are going to Carverfest, go visit Eddie in Cabin 7.  Last year he had his OHM Walsh speakers and I'm sure they will be there again this year.  Great sounding set up!

[UncleMeat 1,173]

 

 

 "Nixon's Colossal Monetary Error: The Verdict 40 Years Later"

 

I agree and I would have said "left the gold standard" except our exit from the gold standard started many, many years before Nixon.  Breaking the last tie to the gold standard gave the government the ability to print even more worthless dollars and (probably) steal all of the gold held in Ft. Knox. If the dollar has no association with gold, then why is the government sitting on stored gold that was given to them by taxpayers?  We as Americans should demand that the gold be given back!  

 

That was supposed to be a temporary suspension of the gold standard, but the government found it convenient to continue printing more de-valued dollars so they could continue spending more money without it being tied to the amount of gold that was in the reserve.  By 1976 the US dollar had lost all association with gold for it's value.  Since giving citizens worthless paper works to make people feel happy they have more money in their pocket while becoming poorer, all other countries who used a gold/silver standard followed suit, today no country uses a gold or silver standard.

[LVMAN777 352]

 

 

GERMAN PHYSIKS UNLIMITED II LOUDSPEAKER

King of the Bending Wave

Equipment report

by

Dick Olsher

 | Feb 10th, 2014

"...In the late 1970s Peter Dicks, an inventive German engineer, took up where Walsh had left off with the express goal of improving bending-wave driver performance. Many of his experimental cones used thin titanium sheets and after several years he managed to develop impressive-sounding prototypes. Initially industry interest, however, was nonexistent, and Dicks had to wait for nearly a decade before a loudspeaker company took up his design. Holger Mueller was the right man to commercialize the Dicks Dipole Driver (DDD). After all, he was not only an established conventional speaker manufacturer but also an owner of a pair of vintage Ohm Walsh Model F loudspeakers. He clearly understood that Dicks’ design surpassed the performance of the original Ohm Walsh driver. Mueller proceeded to license Dicks’ driver and worked for two years to refine the industrial design of a new loudspeaker while Dicks continued to perfect the driver. Finally, in 1993 German Physiks was formed to exclusively manufacture DDD-based designs..."

 

"... a slice of sonic heaven at a fair price...."

 

"...Price: $13,500..."

 

http://www.theabsolutesound.com/articles/german-physiks-unlimited-ii-loudspeaker/