sprocket Posted June 28, 2004 Share Posted June 28, 2004 The under the skirt view of all these Moondogs and Erik somehow can somehow follow all the wiring. Very cool Eric. The one with the battery bias is indeed mine. It was assembled by an experienced builder from NJ and not by me. Eric is correct the input was moved to the top plate and the voltage switch on the side plate is for KR tubes which tollerate greater voltage to the plate resulting in some increasde in power. Some report 4.5 watts. The C-5 cap is removed with this mod and perhaps R-2 also. Here is an under the skirt look at her sister. Reg B. Quote Link to comment Share on other sites More sharing options...
jazman Posted June 28, 2004 Share Posted June 28, 2004 ---------------- On 6/28/2004 8:30:40 AM sprocket wrote: The under the skirt view of all these Moondogs and Erik somehow can somehow follow all the wiring. Very cool Eric. The one with the battery bias is indeed mine. It was assembled by an experienced builder from NJ and not by me. Eric is correct the input was moved to the top plate and the voltage switch on the side plate is for KR tubes which tollerate greater voltage to the plate resulting in some increasde in power. Some report 4.5 watts. The C-5 cap is removed with this mod and perhaps R-2 also. Here is an under the skirt look at her sister. Reg B.---------------- Reg, I could have had the battery bias as part of my Moondogs, but chose not to in order to avoid the tweak required every 6 months or so. What are your plans for candidates to replace your Moondogs, if you don't mind saying. Given the nature of things around here lately, I can understand if you'd rather not say publicly. You can always send a PM. Klipsch out. PS. After reviewing the posted photos, it seems the underside of your amp, and the one listed for sale are different amps. I only went back as far as Deans posted shot and should have gone further. So I guess you're not selling yours. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted June 28, 2004 Share Posted June 28, 2004 What do you guys think of the most recent pair of 300B welbornes on audiogon. They have SS rectification, is this a big no no, or are they worth checking out? Smilin Quote Link to comment Share on other sites More sharing options...
sprocket Posted June 28, 2004 Share Posted June 28, 2004 Jazzman, is the 6 mo tweak you mentioned replacing the AA batteries? If so I may have missed that as a requirement for having amps with a battery bias. The batteries have been in my amps for aprox 2 years. About half a year ago I developed a problem with one of them. I removed the batteries which requires some easy desoldering and tested them. They tested ok and the problem was discovered to be just a poor contact between the input tube socket and the tube pins. The problem was solved and I reinstalled the same batteries. However maybe I should have replaced them seeing they were out. Eric what do you think? The batteries should be replaced eventually, but don't they get recharged as the amp plays? Jazzman,I think the picture of my Moondogs was included in this post just to compare wiring skills, not shure. They are not for sale at this time. I like'en too much. Reg Quote Link to comment Share on other sites More sharing options...
Erik Mandaville Posted June 29, 2004 Share Posted June 29, 2004 Hey, Neo: I'm here for some email information, and checked the Moondog thread. I knew you wanted some feedback on the wiring of your amps, and saw the picture you have posted. Based on your initial description, I have to say I expected something much different. Those look FINE! Leave them as they are and enjoy, the builder did a good job on those, and you got that monster Black Gate, torpedo of a filter capacitor, too. I think you got yourself an outstanding pair of Moondogs. Erik Quote Link to comment Share on other sites More sharing options...
Erik Mandaville Posted June 29, 2004 Share Posted June 29, 2004 Neo: I just had another look at the output transformer secondary tap connections on the amps shown in the picture, and they are wired for 8 ohm speakers...but with Electra-Print OPT color coding. Who knows, maybe the two companies use identical color coding schemes as far as the multiple impedance taps on their output transformers(?) I've only seen one pair of Moondogs with MagneQuest OPTs, but they did not have teflon sockets or the upgrade filter capacitor. In any event, those are nicely wired Moondogs. What aspect of the construction are you not happy with? Quote Link to comment Share on other sites More sharing options...
Deang Posted June 29, 2004 Share Posted June 29, 2004 Smilin, If you go the Welborne site, you'll see that Ron Welborne really down plays the rectification issue with the DRD's. According to him, he actually prefers solid state rectification with the DRD's. OTOH, when he goes on the road, what he shows and uses are the tube rectified versions. I suspect this is more the accomodate the hardliners than anything else. I know Kevin ordered his DRD's with solid state rectification, and he's obviously very happy with them. Quote Link to comment Share on other sites More sharing options...
jazman Posted June 30, 2004 Share Posted June 30, 2004 Reg, Sorry,... I took time off for good behavior. I did not pursue the battery bias because I understood the life of them to be generally 3 yrs., maybe as long as 5. I "assumed" bias of the tubes would need to be checked every 6 months or so, but did not pursue it since the original owner had tried it and felt benefit marginal, even though it would be "purest" bias and a "subjectively" blacker backround. Do you have a way to adjust bias for your 6SN7's? I have however found good interconnects from monoblock to pre and amp power chords to be very beneficial to realizing audible improvements. Klipsch out. Quote Link to comment Share on other sites More sharing options...
sprocket Posted July 1, 2004 Share Posted July 1, 2004 Hey Jazman No on the 6sn7 bias question. I don't know of any Moondogs which require bias adjustments. HUM pot yes, BIAS no. Then again M-dogs seen to come in slightly different flavors in accord with builder tweakage. Anything might happen. I have heard that some manufactures with units that require bias adjustments make an easy and cleaver access point through a headphone socket. You use an adaptor connector to the multimeter into the headphone socket and adjustments are made by way of an external screw adjuster. Simple, no need to open up the box. Anyway my M-puppies don't have any adjustment requirements and are silent even connected to my 84 Cornwalls, which we all accept to be 100db/m/watt. I have made some power cables as per Chris VanHaus web instructions. They were fun to make and cheap. I may detect best results with the power cable to the Preamp. Hard to say with confidence. Still fun and cheap works for me. I have never tried any silver interconects even though the wiring inside is silver. More money may be used to explore in this direction someday. Reg Quote Link to comment Share on other sites More sharing options...
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