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Post by mikhail on Aug 1, 2006 23:32:44 GMT
hello im interested in the meier crossfeeds - both of them in fact, the natural and the enhanced bass. at the same time, it would be cool to have a bypass so that the signal is unprocessed. is there any way to do all this - ie, have the options of [1] the natural crossfeed, [2] the enhanced bass crossfeed and [3] bypass. is it possible to do this by using dpdt or 4pdt switches and if so how? any advice would be truly appreciated as ive been scratching my head over this for a bit now. cheers
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xerxes
Been here a while!
Posts: 1,115
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Post by xerxes on Aug 2, 2006 0:26:59 GMT
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Post by mikhail on Aug 2, 2006 15:11:28 GMT
xerxes, thank you so much for that link - it can be done after all now i just need to absorb the schematic that you have on that linked page. the only niggling problem i have is that i have never worked with rotary switches in my brief diy'hood' - have built few tube amps and couple meier and linkwitz crossfeeds[single modules without a bypass] but not a single rotary switch in sight - so yes i do not know how they work not for long though i read that the 'BY' switch was actually a very low crossfeed processor- an unintentional one. would it be ok to stick in there an actuall crossfeed module - for eg, the meier natural crossfeed. the mid and the hi crossfeed could then be hooked up to the enhanced bass and the high crossfeed that 'pinky' had provided somewhere in the same link. thanks again for the help
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xerxes
Been here a while!
Posts: 1,115
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Post by xerxes on Aug 2, 2006 16:55:09 GMT
Oh yes. This was actually the second thing I EVER built! If you've built a couple of tube amps you should be well up to the task. I don't actually use the crossfeed filter. Having built it I found I prefer the sound without it. ;D Do you live in the UK? You can have it for £20.00, which should just about cover the cost of the parts and postage. I appreciate you probably want to build it yourself, but drop me a PM if you're interested.
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rickcr42
Fully Modded
Rest in peace my good friend.
Posts: 4,514
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Post by rickcr42 on Aug 3, 2006 13:55:16 GMT
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Post by mikhail on Aug 4, 2006 0:26:35 GMT
hi xerxes, not really [being up to the task that is] - i am able to decipher most schematics but have no clue otherwise thanks for offering the crossfeed but as you guessed it, i just need to build this one and besides, ive got about 80% of the parts. wtih all the effort that you put into the crossfeed and the way it looks, 20 quid is a pretty good though where is the pm button? thanks rickcr42 for the links - the meier schematic is interesting and am studying it. will be back with more questions cheers
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rickcr42
Fully Modded
Rest in peace my good friend.
Posts: 4,514
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Post by rickcr42 on Aug 4, 2006 2:34:10 GMT
fire away
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Post by mikhail on Aug 6, 2006 2:05:06 GMT
ok here are my not very brilliant questions 1. switch S1 – the first contact in the rotary switch is not connected? The same goes for S2 but in S3, it’s the last contact that is not connected? 2. left in and right are signal only and not signal and ground. 3. The output impedance resistors – R1,3,5,7 and 9 are all tied to S2? [ I’m not sure if R1 crosses over to S2] 4. R15 is tied to C1, R11 and R13? [same uncertainty as above but with R15] 5. If SO connects with C3, the crossfeed is bypassed completely? thats it for now, more inane questions may follow thanks very much for the help.
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rickcr42
Fully Modded
Rest in peace my good friend.
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Post by rickcr42 on Aug 6, 2006 4:52:37 GMT
1-S1 and S3 are strictly for the bass and treble trim and have zero effect on either the crossfeed selection or total device bypass.Disregard totally 2-correct.None of the switches shown switch both signal and ground but only signal as they should.when switching both you can get some pretty nasty "pops" unless you use what is known as a "make before break" shorting rotary switch which maintains a continous ground connection.A typical DPDT or "break before make" rotary will disconnect the ground when switching and that is just like as if you pulled the RCA plugs out while listening to music ! 3-these are bass trim resistors and change the tilt of the frequency response to compensate for any impedance mismatches.Disregard 4-R11,R13,R15 determine crossfeed level along with R17,R19,R21 fpr the left channel (plus C1,C3, and C5 which is common to both channels) 5-Yes.If you totally disregard the bass and treble trims and look at the actual crossfeed circuit (picture a straight line from the left input jack directly to S2 then S0 in the "down" (bypass) position toally shorts out R11,R13,R15,C1 and C3 while disconnecting R17,R19,R21 and C5 so in effect a straight line connection from the input jacks to the output jacks ready for you man,fire away my pleasure
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Post by mikhail on Aug 6, 2006 11:37:16 GMT
hi rickcr42, thanks for the detailed explanation if s1 and s3 are not required, then the schem. would look like this? hope the pic comes through. at the meier site, it appears that the output and input impedance network is to accomodate the various impendances to be found with different equipment. i will be using the crossfeed between my cdp and headphone amp. my present crossfeed, basically a meier natural crossfeed, without bypass, works fine. so i can leave them out of the equation? cheers rickcr42
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rickcr42
Fully Modded
Rest in peace my good friend.
Posts: 4,514
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Post by rickcr42 on Aug 6, 2006 13:09:34 GMT
yes. Yes again.If your network sounds fine then the rest is just in the way.I have always used a 4PDT switch as a bypass but this method is much better being cheaper by far while working as well. Quicky product Plug : The Cross-1 is THE recommended commerial crossfeed network (actually the only one ) and the one I use in my system even though I rarely change any of the parameter switches.The addition of impedance matching/tonal balance makes the device more of a universal "any system" network that would definately be a plus when driven from a high-Z triode output stage though less so driven from a very low-Z solid state source. No affiliation with Jan Meier or Meier Audio but I took advantage of his months ago offer of free pc boards for the Cross-1 and made my own all-out assault version of (all caps off board being HUGE ) that has replaced my strictly DIY build crossfeed
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Post by mikhail on Aug 10, 2006 8:59:41 GMT
Thanks again rickcr42 for the help. i am going to breadboard the thingy first before making it a fixture in my system. yes i read about the very generous gifts by Dr Meier. im afraid i missed that one but good for you i came across a thread on this at headfi and found it very informative and i plan to go through it to the end soon [it is after all quite a long thread ] but there was a post by you contemplating kiwame resistors and some pretty quality parts for the crossfeed. how did it end up? and was it worth the extra cost - i suppose one would only know if a comparison was done with a stock version versus the 'all out cost no issue' version. i like kiwames and i went a little crazy in using nothing but kiwames in the last tubed headphone amp i did - but no regrets. hence my curiousity. cheers rickcr42.
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rickcr42
Fully Modded
Rest in peace my good friend.
Posts: 4,514
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Post by rickcr42 on Aug 10, 2006 14:48:04 GMT
came out very well and is a permanant fixture in my system.I ordered the Kiwames but they did not fit ANY of the pcb holes (should have known better ;D ) so I ended up using Holcos for everything but the 390 ohm and 3K9 resistors which are "off board" with the caps on a terminal strip mounted on the rear panel (drilled a hole between the jacks to mount it ) This terminal strip holds the above resistors which are NOS Allen-Bradley carbons matched up in L/R pairs and I ended up using Orange Drops for the caps due to a problem getting an exact match for the 0.0015 ( 1.5 nf) C3 and C4.I did not want the "tone" to change with network changes even though not my first choice in caps (can be a tad microphonic ). What I am proudest of though is how the cosmetics came out.I had two pices of solid oiled walnut end caps banging around the junk box since 1977 (part of a project box i picked up from the former Lafayette Radio which was once the main Radio Shack competition,the box was destroyed in the drilling,the wood remained ). These end caps are 4.5Wx2.5Lx3/8 inch thick and have a bevelled edge (outside edge) and a flat edge (inside edge) and it just worked out that the width was ideal for the Jan Meier supplied front and rear panels though the rear panel being less high than the front needed something under the bottom edge to get the whole deal to sit level so I used sheet cork with an adhesive side to line the bottom wood panel up to the front panel edge and constructed it thus= 1-built the main board 2-mounted the main board to the front panel 3-built the off board terminal strip module 4-drilled the rear panel hole and mounted the module+jacks 5-ran wires from the jacks and modules to the main board 6-attached the fron to rear panel with wood dowels 7-attached the top and bottom walnut plates "sandwich style" using brass hardware 8-attached four "pimple" rubber feet to the bottom plate 9-used NOS bakelite knobs for the rotary switches looks great though if I were to do it from scratch I would use hardwood panels that were closer to square to get a better front to back footprint but it is NOT ugly even though it does not stack well being shallow front to back. As to the sonics it works in my system (though i still may change the caps at some point ) well with the adjustment range being all I need in a crossfeed network so I can honestly say I am done experimenting in that area and just flip a switch if the mood hits or I plan on listening for extended periods (get a headache from headsphones without a crossfeeed ) The Meier Cross-1 is highly recommended for anyone who feels they need a crossfeed network in their personal audio system (headphone based system) and feels they want an amp other than a Meier audio or Headroom amp to get it.In combination with the bass/treble trim can be adjusted to suit damn near any source and amp combo (then left alone once adjusted ) and works as advertised. The price is in my opinion a bargain considering how much crap is out there for more and when you think about it is about the same as two pairs of middle of the road audio grade interconnects but does much much more for the system in real world terms with a scratch build from the plans an even bigger bargain though in this case the pcb is recommended to keep it tidy considering how many resistors are involved.
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