macdlsa Posted October 28, 2014 Share Posted October 28, 2014 _____________________H6 TUBE PRE-AMP... It's just a small idea sprang from my “twisted” mind just a few days ago, when I decided I had to bring something new to the "Brusaporto Retrocomputing", a small italian retrocomputing/gaming expo. Well, there would already be something new : the three modded heavy sixers I recently set up also with internal stereo audio system. But for me it would be not enough … With an operation of "joint" between two of my hobbyes, I designed, developed and built a stereo preamp with a low-voltage vacuum tube buffer (to avoid having to take to a public event an object with an internal voltage of above 400V, as I usually do…), which fits inside a frame made entirely of Medium-Density-Foam wood and with the FRONT shape of an Atari VCS H6. I had a very-limited available time (3 days, almost 4/5 hours per day…) so I had to abandon the idea of a decent power supply because I was not able to eliminate an annoying "humm" background noise... Then, I replaced it with a normal switching transformer… good quality but not too much “audiophile”… For the rest I have to say… IT “SOUNDS” GOOD : input Mundorf MKP "entry" 2.2uF capacitors ; output MKP AudynCap "entry" 10uF capacitors ; ECC86 Telefunken vacuum tube, selected and with matched triodes . I set up two different outputs, selectable by a 2-way bipolar “ON-ON” switch: one with the two “classic” L/R female RCA PinJacks and the other with a stereo headphone jack, which also made this pre-amp a good-sounding “Output-Transformer-Less” headphone amplifer, but for only headphones with an impedance of more-than-300Ohms… Hope I did it well ! ________________________________________________________________________________ And HERE IS a little "report" of the "Brusaporto Retrocomputing 2014" Really a great day, and, according to the natives, this event had never seen a sunny day like yesterday, so it was great also for the weather ! Oh well, yes, morning was cloudy, but in the early afternoon the sunlight was even annoying (see the first pic) ... but, hey, it’s the end of October, so we couldn’t ask more ! Many exhibitors, of course, each of them highly qualified in their specific subject, many gorgeous materials and also many visitors !!! Here are some pictures of our tables/stands of “l’Alba dei Videogiochi” / theRetroGamesMachine / comPVter / RetroCampus and, OF COURSE, AtariAge ! On this table you can see almost only BOARD GAMES secured by Dino Baldi of the comPVter association and my "usual" Dragon’s Lair Atari-European mini-cab "prototype cab", which I made just last year in occasion of his 30th' anniversary.*** [The DK board game (Italian) and Dragon's Lair (US-Canada) are mine] *** Then, you could see the Marabelli (me) / Miccoli table with some of the newest games for the AtariVCS/2600 and the Mattel Intellivision.Well, Inty’s Space Raid is REALLY BEAUTIFUL !!!Space Rocks for the VCS is a masterpiece !!! Great Darrell Spice! The AtariVox gave voice to Miccoli’s modded 2600Jr. ... playin’ Juno First and hear the "talk" of the enemies is something rather "special"! Thrust + *LIMITED EDITION* has a GREAT stereo audio track, which is pretty unusual for the "poor and simple" audio chip of the VCS ... excellent, therefore, to test the MODDED HEAVY SIXERs : compositevideo, S-video, stereo audio outputs and internal stereo audio system with the two built-in speakers !For t his particular occasion ( almost NO ONE here had never seen an NTSC H6, and PAL H6 are way RARE ! ) I built up the new STEREO TUBE PREAMPLIFER I just talked about at the beginning of the thread, made with the shape of the H6, which provided a nice vintage audio quality together with the two small speakers and a SW, both with a modified livery matched to the amp and the VCS ! My autographed Atari/Sears PONG concludes the exhibition. [ other pics, provided by Stefono Paganini of "Archeologia Informatica" here : https://www.facebook.com/l.php?u=https%3A%2F%2Fwww.flickr.com%2Fphotos%2Fstepaganini2%2Fsets%2F72157648984673361%2F&h=MAQH4kmgY ] ... and the “group photo” outside of the Brusaporto "Multipurpose Center", which sign is missing the first “N”… ! 5:30pm: the sun was almost gone, and a little later we begun to put all our stuff in its boxes and we finally went to our houses, tired but extremely satisfied ! 1 Quote Link to comment Share on other sites More sharing options...
Albert Posted October 28, 2014 Share Posted October 28, 2014 That pre-amp looks awesome, and even better that you created the case from scratch rather than sacrificing a Haavy Sxer! Looks great sitting next to a genuine Heavy Sixer. I love the vacuum tube popping out of the case. Would love to hear how Thrust+ sounds with that setup! Thanks for taking the time to post this. ..Al Quote Link to comment Share on other sites More sharing options...
macdlsa Posted October 28, 2014 Author Share Posted October 28, 2014 (edited) It was my first though, Al ! It would have been a kind of SACRILEGE if me and/or anyone would sacrifiy an H6 or an L6 or even a Vader for such a purpose [ while junior consoles are too small *** and not too much "nice" *** to "accomodate" an audio tube (pre)amplifer inside... ] . Some people told me that it seems like a "fully-restored" console, compared with the other "real" one which shows the signs of aging ! Oh, it sounds as other stereo setups probably do... It could not be possible to talk about "audiophile sound" in this case, but the "magic" of the ("popped out") tube together with the woody finishing give it all a "full-vintage" feeling ! Edited October 28, 2014 by macdlsa Quote Link to comment Share on other sites More sharing options...
macdlsa Posted October 28, 2014 Author Share Posted October 28, 2014 AH ! ... the opened H6 placed on the top of the shelf just next to the TV is the one which has the video issue I talked about in this thread : http://atariage.com/forums/topic/230450-heavy-sixer-strange-behaviour/ It's still in this condition, 'cause I'm waiting for some "hints" to solve the issue... I would not put my hands inside it again until I know what I could exactly do ! Quote Link to comment Share on other sites More sharing options...
0078265317 Posted October 28, 2014 Share Posted October 28, 2014 Very nice. I wish I knew how to do this kind of stuff. Quote Link to comment Share on other sites More sharing options...
macdlsa Posted October 30, 2014 Author Share Posted October 30, 2014 Just a bit of D.I.Y , not much skill is required. Quote Link to comment Share on other sites More sharing options...
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