Doug Schroeder Method, Double ic


I think this topic deserves its own thread , where use double ic through y adapters , from source to preamp, Can’t connect it from Preamp to Amp...For me the result is huge, I can’t go back to single ic....
128x128jayctoy
I got the cables from Audio Sensibility.....They don’t list it on their website but he will make the cables for you.....ask for Impact SE....get 2 cables for each channel (4 cables/stereo pair)...get them configured "single parallel pair".....  no need to use low quality Y connectors
Ah, very good! I'm glad that the Schroeder Method has passed muster! 
Based on the use of the Audio Sensibility Y cables I'm sure the double ICs are gorgeous sounding. 

The body of evidence continues to grow... 
I've got cables incoming too. Not discussing details yet. 
Some oldies are incredible with the Landscape rig and Schroeder Method. Phil Collins "In the Air Tonight" and "Another Day In Paradise" with stunning front to back soundstage depth. Etc.
I found the old RCA Dynagroove and RedSeal classicals to be much better than current records.   (Soundtrack from Peter Gunn, Fiddler on the Roof, Daphnis & Chloe, Bernstein Mass (Columbia) etc.)
I am now Schroedrized......I got all the cables now, plugged them in and nothing blew up.   My first worry was that I ordered too short of cable from my preamp to amp, but no, I measured right...whew...  (about 5 1/2 meters) The sound is congested, little bass, highes lopped off, but after an hour things are better.  I've been CD'ing an Elton John recording, and every song is better than the previous one.  It is so interesting how the cables are changing as they break in.  
stringreen, so now you have three occurrences of the Schroeder Method in your system? 


I have tried the double ic connection via AQ f shaped splitters, between cd and preamp. I hoped for positive outcome, but my somehow short and limited experience was that sound did not improve, I have noticed the change, but the sound I get would be best described as a kind of loudness effect. Perhaps its releted to the gear I use. (tube amp and preamp) I will not desmiss the idea completely, but for know I have no doubt that my current set up is better with regular connections. On the other hand, I am using the Franco Serblin Lignea monitor speakers with Yter speaker cables (same manufacturer,) and I ve read somewhere that doubling the speaker cables produced great results. Perhaps in the future I would be able to check that as well and report my findings.
alexatpos, thank you for relating your experience in regard to Schroeder Method and your system. Every contribution to understanding it is helpful. I wonder if the output of the CD player is a factor in the outcome you experienced. There is a possibility that the capacitance of the doubled interconnects was too high.

One thing that is very helpful in the overall assessment of the doubling of ICs is that it seemed obvious to you that the sound had changed. That in itself is important, because it reinforces the experience of others, that the sound changed noticeably. 

It would be helpful to me and the community if you would share the precise make and model of your CD player, Preamp and Amp so that the specifications could be found, and perhaps better understanding of what might be the issue can be discovered. 

I wonder if you are using a very low power amp and if that might be a factor in the result. I had discussed use of double ICs with Kevin Hayes of VAC and he said it would present no problem with his amplifiers. But, I hasten to add that the topology of amps, even tube amps, can vary dramatically, so this response certainly cannot be extended to all amplifiers. 

 Again, if we can see the equipment used that would be very helpful to everyone. 
Douglas, by all means,no problem. Here are photos with specs.
The tubes are 6550 and ECC 83, all Tung Sol

http://www.highendshop.gr/images/P/UnisonResearchp30.jpg

P30K Technical characteristics
  • Type : Stereo-mono Valve Amplifier.
  • Output Stage: single ended, ultraliner, parallel
  • Classe: A pura
  • Output Power: 30 watt ( stereo ), 60 watt ( mono )
  • Output Impedance: 4 – 8 – 16 ohm ( stereo ) 2 – 4 – 8 ohm ( mono )
  • Input Impedance: 47 Kohm / 50 pF.
  • Feedback factor: 15 dB.
  • Valves: 2 x ECC83, 4 x 6550 / KT88
  • Power Consumption di Potenza: 280 VA
  • Dimension: 275 x 460 x h 200 ( mm )
  • Net Weight: 28 Kg / 61,8 lb
C5P Technical characteristics
  • Type: preamplificatore valvolare line / Phono*
  • Class: pure A
  • Inputs: 3 line, 1 phono*
  • Impedenza d’uscita: 800 Ohm
  • Input Impedance : 47 kOhm line, adjustable phono*
  • Gain: 52 dB phono*
  • RIAA: passive ± 0.2dB*
  • Bandwidth: 10 Hz ÷ 100 KHz
  • Valves: 3 x ECC83 line, 3 x ECC83 phono*
  • Remote Control: radio for volume
  • Power Consumption: 25 Watt
  • Dimension: 10,7 x 21 x 7,9 inches
  • Net Weight: 22,5 lbs
Player is MF, modest one, its on the loan, I can check the model if needed. Its not near versatile, regarding its functions (changing of gain) as my previous Dcs player, so I express some reserve about it. The cables used are HiDiamond D2 xlr, configurated to rca. Here are the specs for them too

https://www.dagogo.com/hidiamond-d2-and-d7-interconnect-cable-review/
Right Doug....2 -1 meter pair (phono to preamp, silver disc player to preamp) and 1- 5 1/2 meter pair from preamp to amp. Still not broken in.....interesting the 1 cable that is oldest is phono to preamp.... phono sounds WAY better than CD.  All balanced XLR cables
alexatpos, thanks for providing the info on the specs. Those look like very fine components with class A tube power; I'm guessing very sweet sound. 

One thought that strikes me is what appears to be three outputs, 4,8, 16 Ohm. Are you by chance using the 16 Ohm output with the Schroeder Method cables? I'm wondering if that would introduce the effect you are hearing. Is your system appropriate to try the 4 and 8 Ohm outputs, i.e. speakers appropriate? It would be interesting to see if the output influences the result of the Schroeder Method. Please confer if needed prior to attempting. But, it sounds like you know what you are doing. 


Stringreen, by saying phono sounds WAY better than CD, are you suggesting that the CD got worse, or only that the phono is enhanced more greatly? It is hard to understand your comment the way it is worded. I'm asking because alexatpos is using a CD player and is not getting a good result currently. It may be correctable. 


Even my wife says she doesn’t understand me.......My thinking is that the cable from the turntable being the oldest of the Schroeders has reached a higher level of performance because the new ones (from the CD player) are still opening up. At this time, the CD player is not what I think it can provide in sonics. With my older silver cables, the turntable sound was better in some ways than the CD player, and the CD player was better in other ways....all depending on the recording. Also, all sound is going via the long preamp to amp new cable.  Of coarse, I’m open to any of your suggestions. ...just as an aside, I’ve played the Purist Audio and Ayre break-in discs but without any progress.
Douglas, the speakers I use, Franco Serblin's Lignea  have minimum impedance of 7,9 ohm, so I have them conected on 8 ohm outputs. I do not think (correct me if I am wrong), that conecting it on either 4 or 16 ohm outputs would be helpful. Perhaps it would be interesting to know if all the people who do not hear the positive change have the similar sounding experience and on which kind of gear
alexatpos, unless there is a reason to take caution with operating a particular speaker on the other outputs, I make it a point just to see what the resultant sound is like to try speakers on all amp outputs, i.e. 4,8,16 ohm. The results can be surprising, and often I prefer one setting that is not aligned with the minimum impedance of the speaker. You will definitely have a different result with each of the outputs. One might be superior. In many instances speakers that were rated 8 Ohm sound much better to me as the 4 Ohm outputs are used. One simply has to try in order to determine which is holistically superior. My point was that it may help to isolate an influence why the double IC is not to your liking. 

Stringreen, if both of the Schroeder Method ICs are similar type, ie. XLR, you could swap the short one with the longer to see if there is an immediate degradation due to the length. Set up the rig and get used to the sound again at baseline. Then swap the two double ICs for comparison. Could be interesting. 



Douglas, speaker outpus on tube amps are not exactly correct. It is generally known that factorys declare a ’middle’ impedance. The lower the impedance of the nominal is the bigger problem, so the transformers are counted with that in mind, typically the 4 ohm output is calculated for about 3.2 ohms and 8 ohms for 6-7 ohms. So, one level of flexibility is already included in any construction. 2) The operation of the speaker impedance above the declared on the amplifier increases the damping factor, decreasing the output power and distortion - until the moment of clipping. Working with lower impedance reduces the output power but also increases distortion. Having all that in mind, I prefer to stick to predictable solutions (right output for known impedance)
But, thank you for your advice, I do believe that is important to have an open mind, more so in audio, because there are lots of things that laymans or even experts cant explain and yet they are audible
doug - do you plan on reviewing any of the Exogal Vortex streamers ? Simple yes or no will suffice . Thanks,mike
Doug....there is no doubt about it now. The Schroeder cables are the very best I’ve heard in my system. I’ve tried many levels of Cardas, Kimber, Purist, Wireworld, Audioquest (interesting to me is that the ultra high level of Signature cables was not nearly as good as their top lesser grades), etc., etc. None have the openess, dynamics, depth, etc. as your cables do....and far less money. Bravo! Perhaps each system just has its preferences...I don’t know. It takes a couple of days to find the gold, but for those who are trying it, be patient and enjoy. It was so interesting to hear the journey. At first....rolled highs, no real, but tubby bass, no air. All the sound seemed to be coming from the left speaker grill cloth. I even checked the attachments to see if I wired it correctly. I really couldn’t hear as it was changing....just a realization that the soloist was now dead center...then came the openness..... The low bass was next. I have Vandersteen 5A speakers which was set up by Vandersteen himself who proclaimed my room was just not capable of those really low tones....yet...they are now evident....they are clean, pitch specific, and fully incorporated in the sonic picture. I can go on, but I simply encourage all to try these cables in your own system.
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There is certainly something going on with the Schroeder double interconnect (DI) arrangement.
I'm have two sets of DIY DI's which I've made up with low cost Mogami w2534 star quad microphone cable - terminated to single xlr connectors, i.e. no 'Y' adapters. The DI's are between my Benchmark DAC3L, HPA4 pre and bridged mono AHB2's
I'm getting greater apparent dynamics/impact, better separation and dimensionality to instruments/voices  - which seem to be presented in bolder relief with better timbral detail - and a more expansive feel to the soundstage but without loss of focus. There is also a non-fatiguing quality to the music that doesn't seem to impact detail.

I'd still like to do further listening to see if there are any negative consequences to these changes.
What strikes me the most about is not that these changes cover a wide range of attributes or characteristics of sound quality; I find that cables globally influence the system's sound. What amazes me is the degree to which these changes happen with the Schroeder Method. The effect is far beyond what I might have predicted. I thought there might be a deleterious effect, but instead there is a very strong improvement across the board.
I have been looking to update this thread with recent activity. Steve from Audio Sensibility has been sending me Y cables, both RCA and XLR, for assessment and write up. That is underway. He has also been working on a Schroeder Method double IC with his own particular twist. 

Meanwhile, I have used the double IC on a very heavy hitter speaker system with outstanding, nay, spectacular success. I will say this; it was paired with the previously mentioned Benchmark AHB2 amplifier, and the result is glorious. Other amps tested to follow. 

The outcome of all this is so far beyond expectations. I'm still looking for input from another manufacturer to see how far I can take this. This is no minor improvement, this is an ultra-efficacious method. 

(For those just joining, please see the discussion on appropriate systems for use with Schroeder Method. Do not presume any and all rigs are appropriate. At this point there is in place a caution regarding class D amps. That may change in the future, but not at this point. This is a do at your own risk activity.) 

My responses from manufacturers, designers, etc. in regards to the suitability of trying, and the efficaciousness of Schroeder Method has covered the full spectrum. Some laugh it off, while others discuss potential issues that they feel the Schroeder Method should be avoided. Yet others find it fascinating and say they will try. Some feel it's benign in terms of what equipment it could be used with, and the most recent tech with a background in electrical systems said it will always improve a system. He feels I stumbled on to one of the few absolute ways to improve signal transfer.

That's not an official go ahead to try with class D amp! 

Has anyone tried the SM cabling from a preamp to a NuPrime STA200 amp? This NuPrime amp as a bandwidth of 10 Hz to 100kHz (-3dB at 900kHz). Could be magical....
I fell in line with the Schroeder Method and am reveling in the spectacular performance.   The aural picture is so real I feel as though I've stepped into the performance.  I can follow each single instrument and appreciate what it brings to the piece.  I replaced uber expensive silver interconnects....and would not change back.

Let's bring this back to the foreground. I'm not surprised that it is sitting quietly now; there are enough cautions that many will not try it. I suspect that only the most adventurous have done the Schroeder Method. I also suspect there are others who have tried and not reported back yet.

Meanwhile, the results have gone from wonderful to astounding. I just put together a Schroeder Method XLR with Clarity Cables Organic ICs and I'm astonished at the result.  I'm building better and better systems with it and there seems to be no limit in sight for improvement of the sound. 


I run mogami balanced cables . I have a spare set here.  How do I I incorporate the second set ? 
Just wanted to share I have made some for my customers and they love them. Folks are contacting me about these so there is still interest.  Folks reading here don’t neccessarily post. 
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Hello everyone.  Tried the basic Schroeder method 3 weeks ago but did not post then because I am the skeptics skeptic.  I removed and replaced the cables 3 times because I disbelieved my own ears.  I finally invited 3 audiophile friends and did a "blind" test.  They were shocked to put it mildly.  All three have read this thread as Grannyring surmised and all three doubled up on ICs to pre amp.  Since I am bi amping Hi's and Lows thru a Marchand crossover I am trying to solve the mechanics of doing a "Schroeder" to each amp.  Thanks Doug--such a vast improvement to an old school system.  PS.  I am using a TBI sub amp that is class D but only running that off a pre amp with a single rca.
Very nice feedback, especially from our "skeptic's skeptic"! Kudos for trying! Yours is the kind of response that should get people thinking. I presume your friends found it worthwhile. "Vast improvement" is an accurate description, not exaggeration.

Elizabeth, I have changed resistors and caps on the PureAudioProject Trio15 Horn 1 Speaker with nice results, as well as the "internal wiring". So, I'm not surprised that there is a difference in doubling resistors.

maplegrovemusic, if you have not read my article on Schroeder Method at Dagogo.com, and associated discussion, you should. At this time there are certain precautions in place to prevent potential problems with unknowns, i.e. not at this time recommended for class D amps. Do not go blindly into a "do at your own risk" activity. To do XLR Schroeder Method you need standard Y cables to double the cables, then a pair of what I call "reducing Y cables" that are double female to single male. Most that are found commonly are garbage, and sound accordingly. Audio Sensibility (under review) has the normal Y cables for XLR, but has added the reducing Y cables for XLR due to Schroeder Method.  
Thanks Doug , I think I will have Grannyring - Bill, make me up some with the Dueland wire . Don't worry . I will not be using them with the Exogal ion/comet I have . I take it you have not tried it with your Ion ? Or have you corresponded with the Exogal team about it ? Thanks,mike.
I have used the Exogal Comet alone with Schroeder Method several times, and in fact now it is in a system that has blown out of the water the previous conclusion of what that DAC can do. Some radical results happening lately. 

I have not tried doubling the umbilical between the Comet and Ion. Most definitely I would have to talk to Exogal first to see what they thought of it. I like the idea of extreme improvements, but I also like the idea of not blowing up stuff. 

@douglas_schroeder  Would love to learn your results of doubling the umbilical between the Comet and Ion, should Exogal approve.
david_ten, yes, that would be fascinating, as the combo is superb even without the Schroeder Method. With it, I presume the results could be very disturbing for some extreme equipment manufacturers. 

I will contact Exogal about this. 

As per conversation between Jeff Haagnestad of Exogal and myself he is strongly against doubling the umbilical between the Exogal products. He went into several technical reasons why it would not be good, and so I will not recommend it. I do not typically dismiss manufacturers' recommendations on such things.

I have been using the Comet alone with the Schroeder method ICs into various amps with terrific success. I am currently running sonicTransporter i7 and Signature Rendu SE into Comet and direct to various amps. Superb! (These have been reviewed for Dagogo.com)

Right Doug....2 -1 meter pair (phono to preamp, silver disc player to preamp) and 1- 5 1/2 meter pair from preamp to amp. Still not broken in.....interesting the 1 cable that is oldest is phono to preamp.... phono sounds WAY better than CD. All balanced XLR cables
I suspect that the equipment used is playing a role. In the case of balanced connections, if the equipment does not support AES48 (the balanced line standard) that you will hear improvements along this line. If the equipment *does* support the standard I would not expect any difference.

Just for fun though, I'll try it in my system. Our preamps have dual outputs so no need for a Y adapter at that end anyway.
Atmosphere....kindly post your findings.....I have a balanced system, am using Doug's system with no Y connectors made by AudioSensibilies, and have experienced a great improvement from regular XLR's











Atmosphere....kindly post your findings.....I have a balanced system, am using Doug's system with no Y connectors made by AudioSensibilies, and have experienced a great improvement from regular XLR's
I will. BTW I'm pretty sure the Aesthetix preamps don't support AES48, so your experience makes sense.
I just finished building a pair of Doug S. double balanced ICs using Connex/DH-Labs BL-Ag solid silver bulk cable, and compared that to a single run of the same cable.  It's not a fair comparison, as I also replaced standard Neutrik connectors with premium Bocchino XLRs with solderless terminations.  After a few hours break-in the improvement is spectacular-- detailed, smooth on top, organic mids and LF, and a deep wide soundstage.  The application is a 2M balanced run between an Esoteric K-01X and an Atmasphere MP-1 preamp.  I'll be curious for Ralph's findings as well. 
dgarretson, thank you for putting the faith in me to try it. I'm glad that you are finding it worthwhile.
I will add that I do not find your result surprising, as you have made an extreme double IC. Schroeder Method seems to be efficacious with all ICs, regardless of quality, but the pedigree of the IC makes a pronounced difference in the rend result. Think of it as leveraging the quality/character of a single IC. I do not find the fundamental characteristics of ICs to skew toward an entirely different set of characteristics when doubled, but rather  to be vastly intensified. 


OK- I tried this in three applications.
The phono cartridge is a balanced source and low impedance. I used the Atma-Sphere MP-1, which supports AES48. At the input of the preamp, this isn't a big deal but at the output it is. More of that coming up.
The phono input didn't seem to make any difference with an additional cable in parallel. BTW this would have cut the resonant frequency of the cartridge and cables in half (but that resonance is well into the upper 100sKHz with dual cables).
In the CD player however the difference was an immediate improvement. The CDP is single-ended.
On the output of the preamp I could not make out any difference. The connection to the amps is 30 feet long, but the preamp supports AES48 and can easily drive 100 feet. So the additional capacitance and connection resistance is a non-issue for it.

At present I don't have any balanced gear that does not support the standard so I can't comment about that. My surmise about what is happening here is that the connection is what is important- it would be interesting to try just running dual connectors into a single cable (sort of the opposite of a Y adapter) and see what happens.
atmasphere....that’s interesting. I have all Ayre balanced, and am using Doug’s cables and I hear a definite difference....not questioning you, just my 2 cents.
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