Hi Nico, Like most nerds, i've done crazy stuff to get the "best" sounding Hifi system while studying at Delft University. That is now over 30y ago. More and more I realized that i'm not buying stuff because my supplier tells me that its the best, but that I buy it so I actually ENJOY the music I'm listening to. I found that I like music played in the style of Monet, rich strokes that touches ones emotions. I dont give a SH*@$ about mesurements anymore. Actually owned an SME30 with 12" SMEV arm and some fancy carts. Moved that stuff out once I found that it stripped the emotion from the LP's. Threw out my DSP for correction and now designed an analog filter for my Orion speakers. Dumped 8 channels classA amps in favor of smaller ones barely capable of producing 5 watts. but it brought back the joy end emotion in the music.
And sure I recognize some of the other stuff as well that you are telling. It is sometimes a struggle to not let that define your life and I thank my wife for helping me with that.
And sure I recognize some of the other stuff as well that you are telling. It is sometimes a struggle to not let that define your life and I thank my wife for helping me with that.
Hugh, my current and only e-mail is nico@ras.mobi There were no .co.za available any longer that I could use my name, hate anyone to think I am hiding something. It is basically a mobile e-mail address. I am on WhatsApp as well, still don't know precisely how to use it, but progressing. It uses my Phone +27 82 415 5002 you are most welcome. I have received a few e-mails from you, but really was not in the mood to debate anyone at that point, don't think I ignored your mails, there was just a time that I could not care **** about anyone.
You are slowly transforming, from what you wrote you had it, then became astray and are now regaining it. A weird change in lifestyle/health triggered my transformation. In reality, I would never dispute that some thought me an audiophile, heck I don't care. I just started to feel unrelated to the movement and decided I had enough, besides it cost me a fortune. That fortune slipped through my fingers in less than 2 years. Keep it up my man, you're doing great!
Your wife must be a darling! I only found my wife real character after 47 years of being married to her (when I stopped being an audiophile)
Just as a side note: I have been in Delft several times and love what we call Holland I can almost speak the language being similar to mine, just some peculiar phrases such as asseblief, which we use as please while you use it as thank you. It always made me wonder how we got it wrong. Many taxi drivers, said assebleif after paying, made me - a bigger tip? Anyway, my wife got lots of Blues and White Delftware) with my every visit. She thought it was antiques... You only see it as heirlooms here, and not very often.
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Since, Hugh let the cat out of the bag, I would gladly write and publish my audio career and subsequent mania, eventual design and philosophy as well as products I spent years on developing using the most sophisticated Test & Measurement equipment available at the time and put my slide rule away at the inception of the HP35 which, at the time cost me more than two months salary while the ZAR was worth twice that of the US$, and SA was the heaviest sanctioned country on earth, except for Gold and Diamonds which the USA needed desperately. Then being laid off by HP due to this absolute sanctions of travel and for any person from or to SA.
This journey was a long and difficult path which led SA to become totally self-sufficient in every respect, becomingthe bread bin of Africa, also a technology giant at weapon manufacture. Developed weapons of mass destruction, super analogue smart munitions that until today remains unchallenged for both accuracy and could not be jammed by any ECCCM measures, even by today's standards.
Our buddies walking the tight rope remaining our only friend, developed spread spectrum technology and frequency hopping military comms, eventually copied by Siemens & Halske., became wide used by the rest of the world regardless of sanctions, developed the first guided cluster bombs with an absolute accuracy of 5 meters and bette We developed the exocet missile, bought by Argentina and sunk a British warship from some distance. I visited our buddies on and off for many years, for obvious reasons. Had them to develop SAW our delay line through tight security, performed many test blasts with them on a Rock Island owned by SA near the South Pole.
Personally befriended and worked with some top nuclear and electronic scientists aeronautical designers, and manufactures, whom also bought weapons grade Uranium from SA from technology we had almost probably since 1960 at Pelendaba, which is now wrecked by the current ANC Government and import fuel for our only nuclear power station Koeberg, simply sold off stuff, neglected maintenance, cadre employment for their personal gai,n cars, buying, offices, funding personal vehicles etc, Zuma had a watch collection of several million Rand.
Our, buddies knowing exactly what Iran is up to and strikes their enrichment facilities as often as they need. Still have the most severe Apartheid laws in the word, but nobody seems to care. Why only us?
I developed FAT CAT the name speaks for itself using SAW technology that was not available from the USA to anyone radar student. Smuggled a handbook book via our buddies, written by Prof John Cambel and Prakash Das from some Canadian polytechnic, still have it today which was the grass root of our ECCCM on our airborne platforms.
RSA was the first country to sign the Nuclear Proliferation Agreement, I signed an NDA not to divulge any tech developed, Today you find SAWs in TVs and any RF equipment at a dime a dozen, but cost us millions to develop, was shared with our friends from the out set. Changed the substrate from quarts to lithium neobate with the assistance of some very smart physicists. Our only buddies had the most advanced production facility to fabricate interdigital fingers within our sphere of friends and made three units to my spec. Cost us several millions at the time.
Personally tested the altimeter using a Cessna flying straight to vertical rock faces in the Drakensberg and only pulled away at 400 meters, while the sliding door was open, trying to simulate actual Doppler shifts for a spread spectrum echo return. Nerve wrecking for Peter, pilot an assistant, and I am hanging out of the open door. Never having life insurance. This was my Initiation to audio characteristic, reflection, phase inversion, specifications and some jargon used on the forum today, obviously also my real life interest for the next 40 odd years. If you feel the need to know my audio background as, and I will take some time to write it. Happy days, to all you enthusiasts.
You may wonder at me wearing a Russian general uniform, was that of a friend met in Angola then years later in his restaurant in Magdeburg (East Germany) he was a military advisor in Africa. We were at war with the Cuban defence for in Angola, totally Russian sponsored. Only had a few mirage 1's modified because we could not buy anything due to sanctions. The Ruskies deployed serious SAM7 to Angola, was not even our war, but the CIA insisted on intervening in a local war that had some petroleum interest and keeping it from falling into the enemies hands. We mobilized our citizen force (conscription) invaded Angola, Heavy skirmishes with the Cuban forces outnumbering us almost 9 to1. had very advanced Russian MIGs. Our SAAF could never gain air superiority, they deployed batteries of SAM7s, We developed, toss bombing using seaplanes, the Buccaneer because of its ability to fly at tree top then toss it into enemy lines at steep pull-up. They were cluster munitions, their MIGs became useless since they used then Russian methodology of the time remaining secret in case of COMINT and only gave the pilot instructions after take-off, by then the Buccaneers were gone. SAM's could not see them at this Low altitude. It probably was nerve recking for our pilots. We conquer Luanda within approx 3 days from the order of step-up. CIA gave us nothing, denied all involvement, all at own cost and risk. Sanctions continued until the idiot ANC became government. Yes, seen it, had a note from my doctor, never bought a T-shirt.
Ronald the Russian I met at signing the Peace accord, shook hands with him, he outranked me by far, nice. We became pen pals, sharing much wartime experience, to the extent that we visited each other every year for two weeks at a time. I got sick, caring nothing for anyone, lost contact, maybe he was executed by Putin who knows. That was a pose in his uniform.
I posted in this thread umpteen times, maybe one last time because I am too much will include how nuts I was. Speaker's Isobaric, transmission line, digs down to 16Hz. Tinkering and tweaking this system for close to 20 years, the stand includes quite sophisticated horn loaded Mid-bass to augment the sharp leading edge because the woofer has so much mass. I have zero sound problems', hut suffered from faint hum. now and again. Paced a chart recorder in the power line and soon solved it completely. Noise floor now close to -103 dB, below full out. Not a TV guy just plonked it there incase I want to see album art.should it be there. I have no woodworking skills, and our local wood supplier made it to drawing, that was never listened to until their arrival. There is no simulator anywhere to analyse the speaker cabinet. Power is derived from 8 power amps preset to max 20 watt per amp, 10 dB below clipping. Never crawled round on the floor to hear bass, was never needed. This is a simple three-way design, utilizing Linkwits-Railey topology. My reference amp RAS-ELD. Few years after posting its basic topology encountered now infamous amp with massive DIY following being identical to ELD, my initial topology followed Toshiba app note, which was very simple but modified heavily now very complex, not even resembling the App note. These are all class A, as you may notice, I opted using Seebeck effect that drives small low noise fans as soon as temperature differential between this and ambient reach a preset threshold. Case temp is only 8 deg centigrade above ambient and remains infinitely stable. Higher bass mid in sealed cabinet above woofer. A little edge refraction from tweeters, but later solve with a bit of self-adhesive foam. Internal stuffing, real sheep wool and 20 mm thick bitumen panels.. Open speaker reveals ISOBARIC chamber. Speakers were a pain to find, four of these matched is almost impossible, but doable. Cross over set to 30Hz.; 70 Hz followed by 3000 Hz (mid/bass to tweeter. Was almost impossible to design a crossover with so many elements and poles to integrate have ruler flat frequency response as well as their effect on each other, then opted for active using the best sounding op-amps available to me including two Krellish KSA 50 amps, which turned out not so super as I imagined and needed heavy-handed mods to bring them in line with what I liked. Used an actual Grand Piano directly coupled to amp, to calibrate the system with no mics only accelerometers and Spectrum analysis. Adjusted networks as required. Measured speaker movement with differential instrument amps also by accelerometers until the output resulted in zero difference. Room Effects has nothing to do with it. Think of it as anechoic........
Holy Sh** are sure you have enough capacitance there? I am guessing each being 10 000uF. I am curious which output devices you chose. What rail Voltage did you use? That is absolutely stunning build! Well done!
The amount of energy stored can spot weld a railway line together. Class A is an almost constant current load. Problem is you don't gain any headroom at near clipping. However, increase in rail voltage will, as well as improve THD and available Energy. There are optimum capacitance Calc on manufacturers websites. They must have cost you a small fortune.
Class AB behaviour is different and changes everything, I said.
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Hi Nico,
The rail voltage is +/-45V and the project is a Class A/B power amp that use on my case MJL3281 and 1302, the total cost of the cap bank for two power amplifier is around 400Euro, then there's 4*800VA Toroidy supreme series....
I just studing now how to connect in a good way using solid Copper 3mm but cnc machining is very expensive and add PI Filter
The bridge rectifier are 2*120Amp IXYX VBO125-12NO7 each channel
@SDF
In your NVA clone you connected the Safety Earth on the bolt of the xformer.
This is the worst Site to do it! Connection a Instrument e.g. a Scope with safety
Earth creates a shortage of the xformer . Burning the instrument🤖. On the left
there is already a hole on the chassis for better conection.
Stay safe
Ingo
In your NVA clone you connected the Safety Earth on the bolt of the xformer.
This is the worst Site to do it! Connection a Instrument e.g. a Scope with safety
Earth creates a shortage of the xformer . Burning the instrument🤖. On the left
there is already a hole on the chassis for better conection.
Stay safe
Ingo
Hi ingo50 and Zen mod! You're totally right about the earth on the transformer bolt, it's not the best thing to do but I took care to not have a ground loop (it's a wood case). I did it 15 years ago by simplicity to rapidly try the amplifier and it is keeped like that and works pefectly since!
Hello,
I design them myself and add speaker protection. I oder them at jlpcb.