Mallette Posted September 20, 2013 Author Share Posted September 20, 2013 Or you can try the setup in the pdf that only uses an additional rear speaker and an l-pad to control the level. That was Hafler's original inspiration, simply connecting rear speakers out of phase to recover and route the delayed returns and a level to control them. The rest of the QD-1 is niceties and convenience factors. Dave Quote Link to comment Share on other sites More sharing options...
DizRotus Posted September 20, 2013 Share Posted September 20, 2013 Dave- Now I wish I'd beaten your friend Ron on that QD-1 for $15.51. As the attached photo shows, the QD-1 I "won" on eBay after making a best offer of $35 ($48 including shipping) was a kit that appears to have been built by Stevie Wonder . . . when he was still "Little." The soldering is abysmal. Note the completely unconnected wire in the lower right. Most of the the red wires . . . wait, they're all red . . . have soldering iron brands on the insulation. Like yours, mine lacks the little black plastic handle from the BALANCE CHECK, otherwise it's all here. I'll clean it up and replace all of the wires. It should be better than new. I doubt I'll get to the point of testing it this weekend. In addition to resurrecting this, I need to reassemble the second pair of single driver BR speakers. EDIT: 9/21/13 My usually empty social calendar now has a gathering of old (that's redundant) college friends to watch MSU lose to ND, while demonstrating just how mediocre both teams are, as well as the rest of the B1G (not including the Buckeyes, which might be the real deal). I'd like to hear about Ron's score. He got a good deal. Actually, I don't feel too bad about this purchase, especially given the prices that some QD-1s have fetched on eBay. One eBay optimist is currently asking $9.95 for the sticker from the bottom of one of these. Quote Link to comment Share on other sites More sharing options...
DizRotus Posted September 20, 2013 Share Posted September 20, 2013 ARGH! Well, that soldering can be fixed up pretty quick. Shouldn't be too bad. Those knobs have been used on many things. You might be able to scare one off an old tube tester or old low end reciever with slides. Hope it works out. Mark, Fortunately, the round metal knob is there. The black plastic knob on the BALANCE CHECK has been replaced by the white plastic thingie. You'll notice a ready supply of new red wire. I'll try to keep this original in case I want to enter a conours d'elegance. [] Quote Link to comment Share on other sites More sharing options...
DizRotus Posted September 21, 2013 Share Posted September 21, 2013 Due to the need to totally rewire the newly acquired QD-1, I located a pdf version of the manual that includes the assembly instructions. The version attached earlier in this thread (and ubiquitous on the Internet) was from a factory wired unit and lacked the pages regarding assembly. After repeatedly finding the pdf of the manual with the same serial number, I stumbled upon: http://www.hifiengine.com where I located a pdf version of the manual that included the assembly instructions. Pages 14 - 23 of the full length version are attached in 2-3 page segments to this and the next three posts. The size of the entire pdf required that it be broken down to smaller files, each within the limits of the forum's server. BTW, the Hi-Fi Engine site looks to be a valuable resource to the audio hobbyist community. I'd not run across it before. I'll post a separate thread in the Updates & Modifications section about the site. Quote Link to comment Share on other sites More sharing options...
DizRotus Posted September 21, 2013 Share Posted September 21, 2013 Pages 17 - 18 Quote Link to comment Share on other sites More sharing options...
DizRotus Posted September 21, 2013 Share Posted September 21, 2013 Pages 19 -21 Quote Link to comment Share on other sites More sharing options...
DizRotus Posted September 21, 2013 Share Posted September 21, 2013 Pages 22 - 23 Quote Link to comment Share on other sites More sharing options...
DizRotus Posted September 21, 2013 Share Posted September 21, 2013 Nice find for both the assenbly and the HiFi engine site. BTW, that little "high hat" knob for the slider was used on zillions of older instruments in that era. That's not a Dynaco unique part. If you have an electronics junk yard of any kind in your area, you could probably prowl it and find one. The last tube tester I had used the exact or very similar knob. Good luck with the project! Thanks for the tip Mark. I'm sure I can locate an acceptable black knob. I don't want to lose points for originality.[] Quote Link to comment Share on other sites More sharing options...
whatever55 Posted September 21, 2013 Share Posted September 21, 2013 Just checked ebay and looks like they are about $50 + Quote Link to comment Share on other sites More sharing options...
DizRotus Posted September 24, 2013 Share Posted September 24, 2013 The QD-1 has been re-wired. The solder connections are now good. The pots and 3-position switch were cleaned. The DVM indicates the wiring, switches and pots are functioning as intended. I won't know for certain until I try it, perhaps by the weekend. I have to prepare some speaker leads to work with the crowded binding posts on this thing, as well as re-assemble a pair of speakers. I briefly battled the urge to substitute heavier gauge wire for the solid copper wire. But, fortunately, I've been inoculated against testosterone poisoning (doesn't a vasectomy have that effect?). Given the size of the tiny soldering tabs on the 3-position switch, anything larger would have been extremely difficult to solder and would have resulted in a messier project without commensurate benefits. Quote Link to comment Share on other sites More sharing options...
Mallette Posted September 24, 2013 Author Share Posted September 24, 2013 The QD-1 has been re-wired. The solder connections are now good. Looks great. Looking forward to hearing your response. Remember that my experience is to turn it down if I really hear the rears. Just enough where they aren't simply an echo of the front. Also, I've seen little effect on most digital sources for reason I don't fully understand. But on good LPs, especially single point stereo miking, you can get some real depth and sense of space. Interestingly, the opposite extreme of heavily mixed and overdubbed stuff is where you get discrete, sometimes downright startling, discrete stuff from the rears. Just live with it an experiment for a while. Regards, Dave Quote Link to comment Share on other sites More sharing options...
DizRotus Posted September 24, 2013 Share Posted September 24, 2013 The QD-1 has been re-wired. The solder connections are now good. Looks great. Looking forward to hearing your response. Remember that my experience is to turn it down if I really hear the rears. Just enough where they aren't simply an echo of the front. Also, I've seen little effect on most digital sources for reason I don't fully understand. But on good LPs, especially single point stereo miking, you can get some real depth and sense of space. Interestingly, the opposite extreme of heavily mixed and overdubbed stuff is where you get discrete, sometimes downright startling, discrete stuff from the rears. Just live with it an experiment for a while. Regards, Dave What effect, if any, does it produce with stereo FM? Also, have you ever tried it with mono recordings? Quote Link to comment Share on other sites More sharing options...
babadono Posted September 24, 2013 Share Posted September 24, 2013 I briefly battled the urge to substitute heavier gauge wire for the solid copper wire. But, fortunately, I've been inoculated against testosterone poisoning (doesn't a vasectomy have that effect?). Given the size of the tiny soldering tabs on the 3-position switch, anything larger would have been extremely difficult to solder and would have resulted in a messier project without commensurate benefits. Neil, [Y] on the rework and soldering of the wiring. I also agree that with as short as the wires in that box are that any increase of gauge would matter. Eric Quote Link to comment Share on other sites More sharing options...
Mallette Posted September 24, 2013 Author Share Posted September 24, 2013 FM would likely depend on the source, which is mostly digital these days. As mentioned, it won't hurt anything. With mono, I can assure you it will do nothing. I've mentioned before I use mono to judge stereo imaging quality. If your imaging is good, a mono recording will have an uncanny presence dead center between your front speakers. With the QD on, at most it will move towards you a little depending on rear level. You can't have out of phase info with only one channel. Remember, we aren't synthesizing anything here, only playing what is there in the orgional context. That's why it's so effective with two mike stereo. The reflections of the direct sound of the instruments arrive back slightly delayed setting up a phase difference with the direct signal...mirrored, but much lower in amplitude and a few milliseconds out of phase. The QD circuit uses that difference to route the out of phase stuff primarily to the rear and the result is sort of "stereo on steroids" with a depth dimension. Stuff recorded in heavily treated studios won't improve much, and stuff with lots of mikes and mixes will be a bit unpredictable...sometimes really cool, other times you may find a drum or guitar to your right rear or something. Engineers correct me if I am wrong on that. Dave Quote Link to comment Share on other sites More sharing options...
DizRotus Posted September 25, 2013 Share Posted September 25, 2013 Dave, Do you use it with R2R and/or other tape formats, as well as vinyl? If so, how does it work? Which produces the best results? Thanks, Quote Link to comment Share on other sites More sharing options...
Mallette Posted September 25, 2013 Author Share Posted September 25, 2013 Anything analog seems best. You know I am not a digital basher and enjoy great digital, but I don't hear much happening even to high res digitized analog. As mentioned, the analog experience varies depending on the nature of the recording, but even when it does little it hurts nothing, and at it's best it really provides a hint of a true 360 degree sound field. Played a classic Firesign Theatre LP a week or so back and was totally startled by a very discrete sound appearing to port and astern. Actually glanced that way before I realized what was happening. Back in my stoner days that sort of thing could really get you going. Dave Quote Link to comment Share on other sites More sharing options...
DizRotus Posted September 25, 2013 Share Posted September 25, 2013 No, but the fox did. Squeeze him here, maybe he'll pass another. Now I have to get a turntable. In a moment of weakness, Years ago I gave away my AR XB with SME 3009II and Shure V15 III. Must've killed too many brain cells in my stoner days to do something that stupid. I'm into this project too far to quit now. A turntable is in my future. I've got my eye on one on eBay just like, including cartridge, one of the two I used in my mobile DJ biz 37 years ago. Quote Link to comment Share on other sites More sharing options...
Mallette Posted September 25, 2013 Author Share Posted September 25, 2013 No, but the fox did. Squeeze him here, maybe he'll pass another. Hey...don't be passing fraternity stuff in public. Dave Quote Link to comment Share on other sites More sharing options...
Marvel Posted September 25, 2013 Share Posted September 25, 2013 We're all bozos on this bus... go ahead and squeeze the wheeze... Quote Link to comment Share on other sites More sharing options...
DizRotus Posted September 25, 2013 Share Posted September 25, 2013 We're all bozos on this bus... go ahead and squeeze the wheeze... That's the truth. "We can't talk here" Regnad Kcin Quote Link to comment Share on other sites More sharing options...
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