Details on the remarkable PROTON D540 Integrated amp's huge 530 watt power output.

Gentle reader,

I have written about the marvelous series of amplifier that PROTON once produced with their exclusive and very effective Dynamic Power On Demand or DPD as they called it.

I wrote in the first article: They designed the power amplifier section with two transformers and sets of capacitors. In normal operation it is Class A. When a crescendo (I love that word, say it out loud: cre-shen-doe) happens, super-high-speed switches cut in the second transformer and it provides the needed power, up to 150 watts into 8 ohms, 280 into 4 ohms and a staggering 530 watts into a 2, yes a TWO ohm load! It will last up to 1/2 second! It revolutionized audio thinking. Hirsch concluded that this design practically negated the need for large heavy expensive and power hungry amplifiers. It was more than capable of meeting 99% of music needs for a fraction of the size, weight and price of far more powerful amps.

First, here are some photos of one of mine, I have two, one as a spare:

Less often used controls are hidden, above.
Above shows their DPD logo.

There are those that refer to PROTON products as being NADs of another name. I was looking at NAD amps on eBay and came across one that was very similar on the rear as PROTONs. The differences are inside. I should have saved a photo of the inside to show you, but didn't. Just because a factory uses the same chassis and other common parts does not make them the same items. I saved this photo from one auction of the rear.
Very similar indeed. I wish the D540 had these proper three-way binding/banana speaker terminals. Otherwise, I choose PROTON.

Those U shaped devices connect the preamplifier section with the power amplifier portion. The D540 can be used as an integrated amp, preamp or power amplifier, simply by removing those connectors and connecting to either a preamp into the MAIN-IN or to a power amp from the PRE-OUT RCA terminals. The manual asks that you plug the unused terminals in this case with what's called "shorting plug". I did so when I have used the D540 as a preamplifier.

Now, I will show interior shots and describe what you are looking at:
Above shows the entire interior. Interesting heat sink design with those curved vanes. The heat sink disipates the heat that the power transistors produce while amplifying the music. The large black cylinders are capacitors that store energy from the transformers. The smaller four are for normal 40 watt max operation. The larger two are for DPD output.
The board above is the phono (turntable) section.
Above are the two power transformers that make up most of the weight of the amp. One powers the 40 watts and the below transistors, the other powers the DPD's above 40 watts crescendo signals.
Above and the two photos below show the bottom of the components. Unusual design in having the power transistors on the bottom, but it helps make the chassis more compact.
Above and below are the previously mentioned music power transformers. The smaller (C2837) units provide Class A performance up to the 40 watt threshold. The much larger (2SA1215) transistors enable the music to remain undistorted during peaks of loud music.
I recently had a problem develop with my first D540: In one channel while playing records, a sound like loud Pink Noise started joining the music. An audio expert friend of mine told me the main transistor in the phono section, shown again, below is at fault. Well, I assembled kit equipment when I was young and even troubleshot and repaired our first color TV long ago, but getting into fixing that issue, I will pass.
As a result of that issue, I pulled out the "spare" D540 and swapped the two. But since I wasn't using my super rare Dynaco Stereo 200 power amplifier, I decided to use the new D540 in a preamplifier role. I found it too has a quirk. The balance control works backwards! All right channel sound comes out of the left side and vice versa. So, I simply swapped the cables connecting to the inputs on the Dynaco and all is right in the stereo system again. Below is a link to that blog post:
Stereo System: Time to make some changes: Dynaco Stereo 200 PLUS Banana Plug lesson.

Thanks once again for looking, there has been unprecedented readership lately since I joined the now-closed FaceBook group: Vintage HiFi and Stereo. The quickly are generating multiple hundreds of page views. Your taking the time to read my humble blog truly warms my heart!

Scott  
at 6 comments:

Stereo System: Time to make some changes: Dynaco Stereo 200 PLUS Banana Plug lesson.

Gentle reader,

I just posted a list of all my blogs about my stereo equipment adventures. After this, why not take a look: UPDATED Every Stereo Equipment Blog post I have done!

Here's the deal. I started looking into PROTON equipment because the same company that made them also made the revitalized Dynaco line when Panor Corp. bought the name rights. I always wanted some of that new Dynaco equipment and at last found a Stereo 200 power amplifier on eBay and snatched it up! It was part of the all-new audiophile equipment they were putting out as well as selling new Stereo 70 tube amplifiers. By the name, one can tell a Dynaco amp's output, the 200 is 100 watts-per-channel.

So, I found a PROTON D540 integrated amplifier which has their phenomenal "Dynamic Power On Demand" circuitry. I bought it to use as a preamplifier to replace my Yamaha C-45. After a while, I decided to try it as it was designed. Well, the stuff works. That little amplifier is amazing at producing prodigious power! It took everything I threw at it and asked, "Is that all you got?" OK, I may be being a little silly. If you Google PROTON D540, you too can learn about the magic they achieve from a 40 watts-per-channel amp.

So, anyway, I was playing LP after LP and all of a sudden there was a roaring noise, like Pink Noise, along with the music, but only on the Phono circuit. Fortunately, I had bought a spare D540, via eBay, so I wasn't too concerned.

Since I was going to unwire everything I decided to put the Stereo 200 back to work. I rearranged somethings too. Took me many hours. Here's what it all looks like now, and yes, I DO have the cover for the Discwasher components:
The OPPO universal player (has headphones on top of it) and the Adcom power supply were moved from the right side. The TDK CD recorder was moved from the left side and the D540 was moved (and replaced) from the top right to where you see it now. The Dynaco (and the D540 before) has to be on top to hook up all the speaker cables.

Here's the wide angle  view of the above photo for reference:
And here's what it looked like before, except those Philips speakers now live elsewhere:
One thing I do not like about the PROTON models is the speaker terminals LOOK like they have three-way banana/binding posts, but they do not. They accept bare wire from the top down into the terminal OR some fancy bent-pin terminals as seen below:

As you can see, it makes for some odd restriction on how one hooks up speakers. Nope, one cannot slide banana plugs in those holes. They do not fit, and there is no continuity in those holes either. They just allow the red and black knobs to rotate.
Below is a close-up of the best conducting banana plug in the world next to the bent-pin terminal. Both are made for Nakamichi in China. I know, I had to get the bent-pin terminals all the way from China.
You see that split zig-zag? They make for ultimate connectivity. Sometimes a little too much as they can be hard to pull back out. Note how the outside cover for the bent-pin units have to be slid onto the wire/cable before putting the terminal on the bare copper. The banana plugs go on first and then the outer cover screws on. For the BEST banana-shaped banana plugs, Nakamichi also sells these:
No, they are not levitating. Though the magic of Photoshop, I rotated the photos 180 degrees. MOST banana plugs, even Monster Cable's do not look like these. If you look closely, the have a little bump on the end and the expanded part can spin around. This makes for easy assembly but poor contact. 
Banana Plug lesson is over. Please let me continue the tale by showing how I wire my system to be able to drive up to four pairs of speakers with no danger of too low impedance for the amplifier to handle.
Above and below is the LEGEND LE412 speaker switch I found years ago. Go ahead and try and find one yourself. They seem to have been all sold. What's unique is it has three-way binding/banana terminals AND they are spaced 3/4 for using double-banana plugs which is what you see plugged into it. They are Monster Cable brand and yes, they have spinners.
To secure the switch to the top of the amp, I made round feet out of Blu-Tak which is sticky Playdoh-like material. It sticks but does not leave residue. Those funny looking things on top of the front of the switch are iron weights. I do not remember what they came out of, but they are perfect to prevent the LE412 switch from rearing up like it's doing a wheelie. The LEGEND switch designers never figured someone would use heavy cables like I do. 

The gray, (or is it grey?) cables are Monster Cable M-Series and are 10-gauge copper with different sizes of wires making up the conductors. The theory is bass will flow on thick wire, treble on thinner. Can't prove it, but is sells cables.

Here are the various cables on the wall waiting to be reattached: 
The black cables are Monster Cable Z-Series and go to the subwoofer and from there to the modified Minimus 7W speakers. Both Minimus speaker sets and others I have modified can be found in the links as seen in: UPDATED Every Stereo Equipment Blog post I have done!
Here is a close-up of the Monster Cable Z-Series:
"Z1R Reference Energy Time Coherent Time Correct Winding" is what it says. Again, it sells cables. And they DO sound fantastic which is why they connect to the incredible and ONLY ones in the world, modified Minimus 7W speakers.
The thicker blue and white ones are the larger BLE Design units comprised of ten separate conductors woven together. They are for the Cerwin-Vega LS-12 speakers. The ones sheathed in clear plastic which my wife says looks like umbilical cord, go through the attic into this room and connect to the BOSE 301 speakers in here. My wife bought the 301 speakers for me. She's like that, and yes she does have two older sisters. One is not married. The smaller BLE Designs cables go to the modified Minimus 11 (silver) speakers.  

Below shows the much neater cabling as plugged into the Dynaco with proper speaker terminals:
Those particular Monster Cable M-Series cables are not marked for polarity. So, red and black Sharpies to the rescue. If you are into stereo/surround speakers, buy a digital ohmmeter. They make it easy to determine polarity on speaker wiring.
So you may be wondering just how can I run up to eight speakers at a time? Well, I don't actually. The Dynaco and PROTON both have speaker selector switches which are designed to handle two pairs of speakers in parallel. The LEGEND LE412 speaker switch also has internal resistance for the same purpose. The load never drops to a dangerous level.

You also may be wondering what's up with the black cables plugged into the double-banana plugs on the inputs of the LEGEND LE412 speaker switch? As stated above, the cables go to the subwoofer and then on to the Minimus 7W speakers. To play just those speakers, I choose B on the amp and do not press either switch on the LE412. Should I choose to play the Minimus 11 and/or the BOSE 301 speakers, I simply slide the red plugs out of the double-banana plugs and choose switch 1 or switch 2 or both on the LE412. Also, of course choosing B on the amp. Confused yet? Believe me, it works and I measured the impedance in each case, all is well. Here are the terminals on the back of the subwoofer:
Aren't Nakamichi speaker terminals lovely to look at? They truly are the best and I highly recommend them. As you can see, the Monster Cable Z-Series IS marked for polarity.

To quote the famous and fictitious, Forrest Gump, "That's all I've got to say about that."  

Thanks for looking!

Scott 

 
at No comments:

INDEX PART ONE To Every Article: Stereo, Quad, Home Theater, Speakers And More

Updated April 3, 2020

Gentle reader,
The largest collection of articles are a passion I have had since 1975: Good stereo sound on a budget. As a result, I have had to divide the list of links into THREE PARTS.
 
Early on, I did not know how to add photos to the articles and I was not very verbose in my titles. I have learned a lot since 2008.
 
PART ONE: The list starts with the oldest at the top to newest at the bottom.
 
Thank you SO much for your interest in my humble blog!

Scott
April 3, 2020
at No comments:

BACK to: My First Stereo 1976 Dynaco PAT-5 SWTPC Tiger 01

Gentle reader,
My previous post: COMPLETED: Creating a searchable database of all my thousands of LP recordings. has generated unprecedented response from readers with almost 400 page views the first day which pushed page views to over 100,000! I am VERY grateful to you and all the others around the world that take the time to read my humble blog. When I started I figured very few would be interested. You all have proved me wrong and I am SO happy about that!

I attended High School in the Mile High city of Denver, Colorado in the 1970's. My family moved from there right after I graduated in 1974, to Richmond, Virginia. At the time, I had a plastic fold-up suitcase style stereo that I was perfectly happy with. Or so I thought.

Then I met Phillip. He invited me to see/hear his stereo. His poor parents and neighbors. Phillip had constructed huge plywood speakers with eighteen inch woofers, a six inch midrange and I don't recall what kind of tweeter. Driven by a Pioneer integrated amp that put out 60 watts per channel. He had a Revox fifteen inch reel-to-reel tape deck and I don't recall what type of turntable. He played Pure Prairie League's Two Lane Highway for me and I was completely blown away! It was SO LOUD and clear! I went home, looked at my plastic piece of crap and sighed.

Being short on money, I started with a Quadraphonic receiver, Electrophonic, I think was the brand, it was cheap, had a built-in 8-track which also played Quad tapes, and had a ceramic phono input. Came with four matching speakers. Sounded OK to me. Here is a link to one that seems to be the same one I remember:
Vintage Morse Electrophonic AM FM Multiplex Stereo Receiver 447 & 8 Track Player • $51.00 - PicClick

I found an ad in Stereo Review for a book called Audio Alternative by Mark Tobek and ordered it. With knowledge gained by that book, I set out to build a stereo. 

After thoroughly studying the book and the author's results from his testing and listening, I decided upon a kit Dynaco PAT-5 which was their new flagship solid state preamplifier. Since I couldn't also afford their ST-120 power amplifier, I instead chose South West Technical Products Company's Tiger .01 mono amplifier kits. Two mono 60 watt amps verses the Stereo 120 which had the same output in one stereo chassis.

I built the PAT-5 first which was a good thing because it was much easier and gave me lots of soldering practice. I took it to Audio Art in Southside Richmond. Here is a link to their FaceBook page: Audio Art They tested it and pronounced it ready to use.

Next, I tackled the two Tiger mono power amp kits. I was just 19 and had little electrical knowledge, but even so managed to get them both built and Audio Art stated they each slightly exceeded their rated output.
Above is a photo of a later PAT-5 I owned for a while. Here is a photo of the rear:
I won't go into all the specifics of the PAT-5, but note the speaker terminals which allowed for switching to another pair via a switch on the preamp.

Below are a couple of photos of the plans for the SWTPC Tiger .01 mono amps that I found on the "Tigers that Roar" website:

A clever compact design made so four side-by-side could fit on a 19" wide rack-mount shelf for a Quadraphonic system. Remember, Quad was all the rage in the 1970's a was what eventually became Dolby Surround Sound.

I did not own a camera, other than a JCPenny 110 film camera in the 1980's, until April, 1995. So, below are photos of my stereo in the basement apartment I lived in:
Note that my first PAT-5 had a silver faceplate without the beveled top and bottom edges seen on the one at the top of the page. It is all that remained of my original stereo. The Tigers had died of some unknown reason.
Note one of the two Dynaco A-25 speakers that I also chose based upon Audio Alternative recommendations. I bought the pair from Dixie HiFi also in Richmond. They were floor samples so I got them for $99.00 for the pair. I found out decades later that they had substituted the drivers in one with cheaper ones and stuffed that cabinet with fiberglass. The grilles were glued on at the factory so it wasn't until I detected a buzzing in one woofer and pried off the grilles did I see what they had done. So much for my having "golden ears"! 
I don't recall the brands of any of the other components, other than the Dynaco FM-5 I added later. Note in the photo below that the PAT-5 is missing. One channel had stopped working and I eventually sold it via eBay.
Below the FM-5 is my first CD player. Below is the genuine SEAS woofer and tweeter from the unmolested A-25 that I sold on eBay as well. The cabinets were so bad, I didn't consider finding and buying a pair of the correct drivers. I wish I had.
As far as turntables, and the book's advice, I chose a B.I.C. 940 and I sprang for the walnut base and smoke dustcover. It came with a cartridge, but I don't recall which one it was. Here is a photo from the web of a 980 I found on this blogger's page:POLITICS / THE USA / SPORTS / WEATHER / TRUCKING / LIFE / HEALTH / FAITH/ GOD: 12/1/09 - 1/1/10
I do not know how to credit the photo other than including a link to the page I found it on. I hope that he/she is OK with my using it.
Above is a photo of one of our "mitten kitten" cats, Leah, squeezing past one of the reel-to-reel tape players I owned later. Not clear enough picture to tell any brands. This photo was made with that JCPenny 110 camera.

Below, are the A-25 speakers atop a pair of the infamous "white van" speakers I found in a thrift store. Again, since I do not have "golden ears" those sounded fine to me too:
This image is from this room. At the time, the kids still lived here, so no listening room.

A LOT of equipment has come and gone in the decades since. I've lost a lot of hair too! We do tend to nostalgically wish we could go back in time and tell our then selves to NOT get rid of things, don't we?

Of course, my current components blow away anything I had then, as seen below:
The Philips speakers are gone now and the modified Minimus 11 speakers now sit there.
Since completing them, the screws/washers have been painted black. Here is a link to the final results of the extensive rebuild: NOW finished: Upgrading old diecast Realistic Minimus 11 speakers Part 2.5 

Thanks for looking!

Scott 
at No comments:

COMPLETED: Creating a searchable database of all my thousands of LP recordings.

Gentle reader,

After many, many hours over several days, I have at last completed the task of entering every LP record (plus the few ten and seven inch records) into a searchable database. It was a daunting task, but one I vowed I would complete once I was retired.


Rather than have you have to go back to the first one, here are photos of the LP collection:
Above is the Classical records. Housed in the only commercially made shelf.
 Above is Jazz, Herb Alpert, Baja Marimba Band, Al Hirt, Big Band, and others.
Above is the Classic Rock/Pop on the top shelves and film/TV scores/soundtracks on the bottom shelves.

The shelf I made in 1976 or so, with the help of my then-girlfriend's father. He was a wonderful man and shaped my life in several positive ways. He sold me the white walnut board that were from a tree he felled and had a sawmill cut into rough boards.

I'd started with the Classical records because they are the largest group and I had to start somewhere. Then the Jazz, etc. shelf both of which are in the listening room. I finished with the horizontal shelf (directly above) is next to me in the other room that comprises my double-man-caves.  Below are the results. There are many more fields that they could be broken down to, but frankly, I'm kind of tired!

While all my numbers were perfectly lined up in Word Perfect, here in Blog land, that doesn't happen. My partially-COD brain is SO OK with that.

CLASSICAL RECORD COLLECTION
860 INDIVIDUAL RECORD ALBUMS CONSISTING OF:

BOX SETS                                                    66
DOUBLE ALBUMS                                    14
TOTAL                                                         80

TOTAL ALBUMS                                     860
1+EXTRA DISCS                                     256
TOTAL DISCS                      1116   
PROMOTIONAL                                         8
AUDIOPHILE                                            22
DIRECT METAL MASTER                       2   
COLORED/CLEAR VINYL                       2
NOT RIAA CURVE (NAB)                         1
1812 OVER. W/CANNONS                      18
MONO                                                       136
QUADRAPHONIC                                    26
FOREIGN                                                 344
JAZZ RECORD COLLECTION   

ALBUMS                                                 384
DOUBLE ALBUMS                                 19
TOTAL DISCS                      403
PROMOTIONAL                                     11
AUDIOPHILE                                            1
DIRECT METAL MASTER                     1   
COLORED/CLEAR VINYL                     1
MONO                                                       68
QUADRAPHONIC                                    1
FOREIGN                                                 30
HERB ALPERT RECORD COLLECTION

ALBUMS                                                 55
DOUBLE ALBUM                                   1
FIVE LP BOX SET                                  1
TOTAL DISCS                      60
MONO                                                       8
FOREIGN                                               15


BAJA MARIMBA BAND COLLECTION

ALBUMS                                                12

TIJUANA BAND SPIN-OFFS/TRIBUTES COLLECTION
ALBUMS                                                 6
FOREIGN                                               3

AL HIRT RECORD COLLECTION

ALBUMS                                              24
DOUBLE ALBUM                                1
TOTAL                                25
FOREIGN                                             4
BIG BAND RECORD COLLECTION

ALBUMS                                           182
DOUBLE ALBUMS                           12 TOTAL                              220
5 LP BOX SETS                                   2
TRIPLE ALBUMS                              1
6 LP BOX SET                                     1
10 LP BOX SET                                   1

COMEDY RECORD COLLECTION

ALBUMS                                           48
DOUBLE ALBUMS                           2TOTAL                               50

INTERNATIONAL + BLUEGRASS RECORD COLLECTION
ALBUMS                                         18
FOREIGN                                       15
BLUEGRASS                                   3

MISCELLANEOUS/TEST RECORD COLLECTION
ALBUMS                                       18
DOUBLE ALBUM                         1TOTAL                                          19

CLASSIC ROCK/POP RECORD COLLECTION
ALBUMS                                    257   
DOUBLE ALBUMS                   15
TOTAL                        270
FOREIGN                                   81
MONO                                          7
QUADRAPHONIC                     1
AUDIOPHILE                             1       
CLEAR/COLORED VINYL      1

MOVIE/TV SCORE/SOUNDTRACK COLLECTION

ALBUMS                                 328
DOUBLE ALBUMS                 15
TOTAL                       343
PROMOTIONAL                     11
MONO                                       50
PICTURE DISC                         2

GRAND TOTAL                                      2,199
TOTAL DISCS                                         2,554
                   I decided that I might as well at least COUNT the CD collection. 
I did not count the INDIVIDUAL discs, nor any other parameters such as I have with the LPs.
COMPACT DISCS

BIG BAND                                11
CLASSICAL                           280
COMEDY                                   3
COUNTRY*                              2
HERB ALPERT                       27
JAZZ                                       260
POP                                           35
ROCK                                       59
SOUNDTRACK/SCORE      195
TEST                                         12
WESTERN                                 5
TOTAL                      890
SACD                                        22
HDCD                                       18
GRAND TOTAL                                       3089 
That number is total CONTAINERS holding one or more LP or CD, regardless of the sub categories such as STEREO, MONO, QUADRAPHONIC, FOREIGN,SACD or HDCD, etcetera. 

I decided to stop actively collecting LP records when I looked around and gauged how many I already had. I have bought some CDs but I never cataloged them.

I DID buy a replacement for a Doobie Brothers LP because the one I had was in bad shape. Plus, I plan to buy a replacement for another Classic Rock LP for the same reason. Finally, I plan to buy two Steely Dan LPs to complete the collection. That will bring the LP collection to 2,101.  

I'm almost 61, now retired and even if I played TEN LPs a day, which would be hard to do, it would take me more than 200 days to do so. I DID decide to start playing ALL of the SOUNDTRACK/SCORE LPs starting with the first 007 soundtrack/score. Once I have listened to all 343 LPs and 195 CDs, THEN I will decide what to listen to next.

Thanks once again, for your kindness and patience with my humble blog. SOON another milestone will be passed: Page Views are rapidly approaching 100,000! ALL THANKS TO YOU, MY GENTLE READERS!

Scott

June 30, 2017 
at No comments:
Subscribe to: Posts (Atom)

I bought a NEW Yamaha CD Player! Build Date of April, 2026. Check it Out!

  August 19, 2026 #551 Gentle reader, Most of you are aware that I have been in the home audio hobby for fifty years now. Thanks to the thri...