NOSValves Posted November 17, 2002 Author Share Posted November 17, 2002 Mobile, I was reading thru this post and I new you were getting some coaching from somewhere !! " As my friend Jeff said, "if this is true, the bass boost provided by a RIAA eq would make your CD sound like a hiphop song played full blast in a yellow souped-up Honda with purple tinted windows." I was amazed when I looked at the schematic that you were indeed correct. But now I see someone else was correct LOL !!! Quote Link to comment Share on other sites More sharing options...
mobile homeless Posted November 17, 2002 Share Posted November 17, 2002 Craig, I dont understand why you were so definite on this. I KNEW the PECs had NOTHING to do with the phono stage or especially the RIAA since ALL the inputs go there and they are on the tone controls, hence the line inputs would ALSO pass through these same PEC units giving the line stage the RIAA boost as well. Nothing but common sense here and this part of the schematic was EASY. I said this from the first post. As for isolating the phono parts to the switch, we both worked on this... I sent him some of the discussion, hense his response. He agreed that the PECs had ZERO to do with it. It is the following resistors and capacitors that appear to be advantageous to go ahead and perhaps put some high Q stuff in there if someone is to use the Phono. No need to muddy the issue with the Scott vs EICO mess. See recs in the graphic. Perhaps more could be done to make it better. Yes, these is STILL uncertainty here as well... but this seems right. Maybe more to come. kh Quote Link to comment Share on other sites More sharing options...
NOSValves Posted November 17, 2002 Author Share Posted November 17, 2002 Mobile, actually the confusion for me with this Item is Scotts later models like 222C and 299C and there kit versions have a pec that look exactly the same as this and like I guess I should never assume were indeed tide to the phono section. I never really investigated it further after that and then when poking around and the hum dropped when messing with the PECs it just made sense I guess but whatever. Now I still think that those 4 components per channel may not be all the culprits involved with the RIAA circuit. Wish there was a way to no absolutely for sure. What's strike me as maybe a issue is that my unit and Chris's are humming identically and from the same channel. Wonder if its the channel mounted closest the say the Output transformer. Just a thought. I have physically messed with everyone one of these parts on my amp and there isn't any sign of microphonics from that. I really wonder if the problem also could just be all the connections made thru this switch not making pefect contact and outside interference bleeding in there. On the Scott units I've done like 299s that have point to point wiring of the RIAA circuit I have never had to mess with any of the parts on the RIAA circuit there dead silent but also well sheilded. These parts are not subject to hardly any current at all so the parts shouldn't really suffer like others. So theoretically speaking the parts should not be the culprit. Tha saga goes on ~ Craig Quote Link to comment Share on other sites More sharing options...
mobile homeless Posted November 17, 2002 Share Posted November 17, 2002 I have two EICOS and am going to use the phono stage on both to see if I get any hum from one channel. Also, I think these parts could be moved to the actual 12AX7 area which might really improve things. On the other hand, perhaps the best thing would be to simply put some really top notch parts in the RIAA stage. Film and foil with some top notch resistors. Perhaps the hum can be reduced in other ways. kh Quote Link to comment Share on other sites More sharing options...
NOSValves Posted November 17, 2002 Author Share Posted November 17, 2002 I'll be working on Paul's HF-12 in the next few days it will be curious to see if the hum can be eliminated on these mono versions. Quote Link to comment Share on other sites More sharing options...
mobile homeless Posted November 17, 2002 Share Posted November 17, 2002 I am listening to it right now. I am getting almost ZERO hum but it is VERY VERY important to have a good GROUND with TT ground wire. It has to be securely fastened big time. Without this, there is residual hum that is obtrusive. And there is a light bit of hum left... I bet it can be tracked somewhere. But besides the hum, I think the phono stage needs tweaking with at least a rebuild. I think the RIAA parts need to be very good along with the pre rebuild. I really recommend putting something of quality there. I need to mess with this some more. But yes, there is still some low level hum. But it does sound damn nice but the line stage is better without some nice parts inserted. kh Quote Link to comment Share on other sites More sharing options...
Deang Posted November 18, 2002 Share Posted November 18, 2002 I think this tube amp business is ridiculous. Why would anyone in their right mind want put up with this nonsense. I'm selling everything and buying a nice Sansui integrated. Humming, buzzing, ringing, hot-flashing glass, and Lord knows what else. Whatever benefits in the sound gained are offset by the shear madness of it all. Yes, a nice polite SS integrated amp that just turns on and off and does what it's supposed to -- speaks when spoken to -- and otherwise invisible. Damn, 15 hours until I can fire up the Apollos and try out the Halos. Think I'll heat them horns up real good tomorrow. Punish those whimpy amps for the crap they've put me through this past week. I can hardly wait. Quote Link to comment Share on other sites More sharing options...
No Disc Posted November 18, 2002 Share Posted November 18, 2002 Dean - heh, you got a point there. I'm selling my EICO and getting a Bose roomate. - tb Quote Link to comment Share on other sites More sharing options...
NOSValves Posted November 18, 2002 Author Share Posted November 18, 2002 Mobile, There's a point here that I think should be made. What speaker are you using with your HF-81 ? If there the Monitors I remember you having in your second system aren't they rather ineffecient ?? If they are in the low 90db your not going to hear the noise that I can hear with Lascalas I can barely hear this stuff with my 96db Heresy's but its very noticable with Lascalas and Khorns I'm sure. What makes me question your silent phono section is that its impossible that its silent unless your speakers aren;t very effecient. I had the TT grounded I would appreciate if you would quite treating me like I'm stupid. I'm not trying to start another riff here it just bugs the sh!t out of me when you treat me like I have no clue here. I know a turn table has to be grounded for christ sakes. Craig Quote Link to comment Share on other sites More sharing options...
Deang Posted November 18, 2002 Share Posted November 18, 2002 Craig, this is pretty important -- I wanted to remind you to make sure that turntable is grounded. Quote Link to comment Share on other sites More sharing options...
Deang Posted November 18, 2002 Share Posted November 18, 2002 Craig, BTW -- it's probably the 'black' wire, but I'm not sure. Quote Link to comment Share on other sites More sharing options...
mobile homeless Posted November 18, 2002 Share Posted November 18, 2002 The defensiveness is almost glaring and transparent as a La Scala. I was NOT attacking you at all, just saying if anyone is having hum they need to first find an EXTRA good grounding connection. I had to try several places on my amp to get it lower and lower. Some preamps like my Cary SLP-70 don't even require the damn ground cable at all but the EICO seems especially sensitive to it. Craig, can you drop this defensive response syndrome? If I was as defensive as you in this thread, we would have been in serious trouble 20 posts back. My language in that post was not attacking at all yet you have been critiquing my knowledge of the EICO/reading a schematic/etc since the third post in! And when you were wrong through the entire EICO phono stage debate, I didn't ever say "you don't know what you are doing" or imply as much until you became a bit indignant. On the other hand, you implied THIS concerning my following a schematic as well as knowing the EICO (meanwhile what you were saying was incorrect). Now, when I make a suggestion that I think important, i.e. the importance of finding a VERY good ground contact, it's taken as some form of insult; please, being defensive reveals just what you are trying to avoid so why do it? Besides, I DID say there was still hum to be gotten rid of in my post. So I am agreeing that there MIGHT be a problem with low level hum on the whole if not addressed. Still, for owners, it imperative that you get the TT cable on the best ground you can find on your EICO; move it around and see. This is what I found, at least. On average, I believe the phono stages on all EICOs need to be optimized with QUALITY parts to get the phono stage to match the quality of the line stage. Part of this (getting better sonics if not hum reduction), I believe, should involve replacing the RIAA with VERY good parts such as super quiet resistors ala Holco and film foil caps. Only 8 parts I believe and this might help along with the good stuff in the actual phono pre section. If anyone hasnt done so, the phono stage needs the parts treatment as well (which Craig has done for Chris besides the RIAA). As for the hum, I still think it might be some grounding issue internally as well or perhaps more shielding needed (maybe it is layout). Actually, leaving the parts on the switch might not be too bad but I believe replacing them might be a boon to the sound, hum or not. kh ps- my low level hum is coming from both channels. Also, it appears much like the above examples, mainly when I get over 6-7 via volume. The monitors are not as sensitive as the La Scala by any measure but I tried on both systems to compare my Cary to the EICO last eve. This is mainly what I am referring to although the hum was still noticable a bit on the 90dB 8ohm monitors. Quote Link to comment Share on other sites More sharing options...
@silverfox@ Posted November 18, 2002 Share Posted November 18, 2002 Definately a humdigger of a problem, not setting myself up to know anything. sometimes a seamily stupid suggestion could solve a problem.have you tried running a seperate ground wiresay from closest plug to amp&tt.just a tought. Quote Link to comment Share on other sites More sharing options...
NOSValves Posted November 18, 2002 Author Share Posted November 18, 2002 Mobile, I'm not being defensive ! I'm trying to find out what speakers your listening to and getting a Mild hum. If you are using your less effecient monitors then your not going to hear the hum. Besides I seriously don't think this has anything to do with the grounding of the turn table since it only comes from the right channel of my amp and Chris's and has to be turned up to 6 to get noticeble. The left channel has the normal fuzzy type phono section noise like my scotts produce maybe slightly more but nothing to right home about. I don't think parts changes will solve this hum. But when I have time I will trace it with my scope. This will narrow down where its coming into the signal at. If anyone is being defensive here its you. Earlier in this post I just made a wrong assumption big deal !! It doesn't bother me why are you bringing it up. Whether you realise it or not you tend to treat people like there stupid about the obvious. It just bugs the heck out of me that you would just assume I hadn't researched the grounding of the amp. Heck the amp does the Identical thing with nothing hooked to the phono inputs. Craig Quote Link to comment Share on other sites More sharing options...
mobile homeless Posted November 18, 2002 Share Posted November 18, 2002 "Whether you realise it or not you tend to treat people like there stupid about the obvious. It just bugs the heck out of me that you would just assume I hadn't researched the grounding of the amp." That's me, always treating everyone as if they dont know the obvious, driving the obvious points home, unaware of the person's postition, perspective, or place in the picture. Yep, no help from this end; I'm just out to make a fool out of anyone I can find. You got me! Your dagger-like perception into my psyche has struck so close to the bone, marrow is exposed, and soft at that. Pass the salt, my midwestern buddy! kh Quote Link to comment Share on other sites More sharing options...
NOSValves Posted November 18, 2002 Author Share Posted November 18, 2002 Whatever Mobile I give up !! You know Mobile I really think I am the only one with the guts around here to call you on this habit of yours and thats where the problems begin. I had 4 emails when I got home today from other members ribbing me about hooking wires up right(they thought you were being redicules too !!). I'm not the only one that thinks you can be a little extreme here !! I'm just the only one that calls you on it. Peace Craig Quote Link to comment Share on other sites More sharing options...
mike stehr Posted November 18, 2002 Share Posted November 18, 2002 What I don't understand is how you guys get into those ancient worn out vintage tube amps with worn caps and tubes. My god, it's the year 2002, don't you know transistors rule the land?!! You act like it's 1962 or something! Pull out of it!! Cool! Love opening smilie. Quote Link to comment Share on other sites More sharing options...
NOSValves Posted November 18, 2002 Author Share Posted November 18, 2002 Mike, Your absolutely right I'm selling all this old junk. especially since I just bought 2 more in the last week or so !! This is addicting Craig Quote Link to comment Share on other sites More sharing options...
JCturboT Posted November 18, 2002 Share Posted November 18, 2002 ---------------- On 11/18/2002 9:12:26 PM NOS440 wrote: Mike, Your absolutely right I'm selling all this old junk. especially since I just bought 2 more in the last week or so !! This is addicting Craig ---------------- Whatcha get Craig?? Jeff Quote Link to comment Share on other sites More sharing options...
NOSValves Posted November 18, 2002 Author Share Posted November 18, 2002 Well last week I bought another 299A and this week much to my suprise while I was at work I sniped a real nice 299B I had forgot I even had a snipe setup for it. I thought for sure it would go for $300 or more. I'll be selling at least one of the 299A's when it all settles down. I'll have a 299A in my Livingroom and a 299B pushing my Lascalas. The other 299A will have to get sold and the LK-72 will be auctioned off also. I will of coarse make them avaiable here first. I should sell my Heathkit AA 151 also. Its a sweet little amp but takes a certain person to love its 57 chevy dashboard look. But it has a nice sound to it very much like the HF-81 and is in perfect condition and recapped I would probably let it go for $175 the Scotts will be much higher ! I might sell the HF-81 also but it will have to be offered to the guy that sold it to me first and then to the guy that donated the parts unit to fix it second. I promised them both first and second dibbs. Craig Quote Link to comment Share on other sites More sharing options...
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