Cool stuff!
Today I made a pair new interconnects with attenuators to lower the signal by 20db. Attenuators are always a pain in the ass, but when they are made with special parts like allen bradley resistors. I have used 8 resistors per interconnect. The cables are made with top connectors of Furutech, cotton, screening and special audio wire 4 wires hot and 4 ground. The result is enormes. Off cousre I was adviced again! The attenuators are in the cables and as close as possible to the poweramp. This way the signal strenght in the cables are high. These wires in combination with the new pre have passed the quality of the Classe pre-amp.
The sound is quicker, closer to live music, more organic, great soundstage same level as the Classe. The interconnects and the pre aint burned in yet so it is very prommosing.
The next step is to replace the paper oil capacitors on the output (Not the big ones) with CuTF V-caps. These caps will give the music an even bigger soundstage, better clarity and will sound more neutral.
My old interconnects Kimber KS1136 and Audioquest Sky XLR and the classe pre are for sale!
Yesterday I replaced the paper oil capacitors for V-cap CuTF 1uF. Besides the V-cap I placed a pair of 22uf MKP to feed my Subwoofer. My poweramp has 50K Ohm input impedance and the Sub has 15K Ohm. 10uf for the sub would be enough, but I had a couple 22uf left from a previous project.
The result with the V-caps in comparison with the paper oils is very big. The soundstage became much deeper, more natural, much better control in all frequencies. To much to describe! The V-caps CuTF are expensive, but they realy are an eye opener.
Wijnand, any new tweaks since the capacitor change? Do you still prefer the sound through your pre to the direct to the power amp connection? For example, using you new cable the direct to the amp should sound differently, rihgt?
Hi Alekz,
No nothing! Everything is still the same. It has three months on the clock now with the new capacitors. The sound and realism is on a very high level. I think this system is in a very good balance. A great soundstage, great drive, very fast, deep bass, natural middrange and great hights.
I Have tried the new cabling direct from the DS to the poweramp, but the pre is a real upgrade for the sound. I use a XLR cable for a single ended signal. The ground and the signal ground are separated by capacitors and a resistor. This will prevent earth loops on the signal cabling and better for the sound.
For what concerns the cabling. I took my old cabling and the new cabling to Germany and visited Wolf. We listened to his current cabling and changed his XLR interconnect and replaced it with half a meter 2200 euro Kimber KS1136. The sound was good but in the same grate as his own cabling. Than we went to the home build interconnect and we both and his son could hardly believe this upgrade was possible by changing the cable between the directstream and his preamp. The realism and bass were never heard before on this system.
We than replaced the speaker cabling for the home build cabling. This was for midrange and high frequencies of his IRS, but it came out as a bad match. The speaker cables are great on my system and outperformed the Kimber KS3033 by far.
The latest change in my system is the AV-Streamer.
For wat conerns the Pre-Amp. I’m planning to build a balanced Pre. It wil have a double stereo inductive volume controls. Four Cutf capacitors. But most important is the double powersupply. It will be quite an investment. For something I never heard, but it will be real fun to work on it.
Thanks for asking, yes very happy!
Excellent! Great report
wijnand said I'm planning to build a balanced Pre.Now you are talking! It must be balanced!
But most important is the double powersupply.Do you mean one power supply per channel? Something like Pass Labs x0. I have an x1 with one external power supply. I've heard that one external PS (vs internal, one chassis device) makes the most difference. The second might improve the sound indeed, but only if you have no other weak links in your system. It might not worth the investments.Probably you can test it with one external PS and then add the second one if you are bored or have some extra tax return?
But balanced vs single-ended is indeed a big step.
That’s why I’m planning to build a balanced pre!
But think about this. You have a budget of 3400 euro to build a pre. What will be the best way to go single ended or balanced? When you go single ended you can buy the best volume control and the best capacitors for the job, etc. Or you go balanced with the same budget. No money for an inductive volume control but something for half the price, no Cutf capacitors but something less. Would this balanced pre still be better than the single ended pre. I quess this would be speculative and double the work. Now I know the level that could be reached single ended. I can try to make an even better pre.
For the powersupply. My current single ended pre has a double powersupply one for every channel. They are in one box but separated from each other and separated from the pre. It has two powercords etc. The channels are completely build mono with it’s own powersupply. The powersupply’s are very clean and stable. It’s possible to play for at least five minutes from the moment the powercords are disconnected. But the controller will shut down when it became under 60V or above 65V at the first stage. The 45Volt stage which is the supply for the transistors is still exactly 45V. Only when the tension of the first stage will come near or below the 45V. The tension on the transistor bord will be in trouble. By the way the 45V stage is partly in the pre itself. This to get a very stable buffer near the transistor bords.
huh, what about tax returns? I think I’ve bad news it than will be another single ended pre 
I will report when I made a start, but don’t hold your breath on it.
It looks very nice and I am sure it sounds as good as it looks. Enjoy it. Pride of ownership in DIY rules high regard to most.
Way back when.
I built a few Dynamo kits
also David halfler.
No built the DH500 amp
DH220 amp
a preamp with a pho stage input and a equalizer too. I have all if it except the eq
I still use it and enjoy the nostalga of it.
Not much left of my childhood so it’s soecial to me. How does it feel to build it as an adult ?? Is it due same good feeling ??
also I thought great phono pre amps used a transformer tonus the voltage and then amplified ted s am I correct ??
wijnand said You have a budget of 3400 euro to build a pre. What will be the best way to go single ended or balanced?With this budget for parts you can build an excellent preamp of either topology. But my experience has been at any fixed price the SE sounds better than balanced until a certain point where they all sound superb.
My guess is that this is because the advantages of balanced do not come into play in the typical enthusiast system with short cable runs and electrically clean environments.
That sounds correct but we must consider world class stuff is SE mostly
I do not know why so many people want balanced as there is draw backs too.
Bit as you state here good and better in both
We can name many SOTA products which are SE, but I do not think we can conclude it is mostly SE. It is probably greater than 50% however, probably as much as a consequence of being consumer products.
I agree completely it’s a serious audiophile choice for some. Why I do not know. The concept of balance as to why is not used in most caes. And how many units are not really balanced front to back. It’s a marketing ploy on all headphones. New cables to buy and of course the improved sound in doing so.
I have Amps they do both I cannot hear and improvement from SE TO BAL once I make the levels the same. Most are fooled that louder means better
and this is just not true but it sound fool us to think so
Elk saidMy guess is that this is because the advantages of balanced do not come into play in the typical enthusiast system with short cable runs and electrically clean environments.
It would be nice to have an electrically clean environment. So far I haven’t seen any. Noise, pollution, EMI are everywhere. Plus the balanced design cancels even harmonics. Can be good or bad. Probably it’s the high even harmonics, what makes SET sound sweet and euphonic.
Comparatively clean, squeaky clean actually, in comparison to stage productions, 200 foot cable runs recording orchestras, multiple connections involving racks of many dozens of pieces of equipment, etc. in a pro environment where balanced can be a wonderful thing. A home audio environment is very tidy.
There also is radiation everywhere, but rarely enough to pay any attention to whatsoever. 
A point of clarification: Balanced cancels even order distortion, not even order harmonics properly present in the signal. A good example of balanced cancelling even order distortion is in a push/pull circuit where even order distortion is canceled in identical output tubes working in opposite phase. Yes, if you like even order distortion, balanced is not your thing.
Yes, I meant non-linear distortions, not the even natural harmonics, of course. Thanks Elk.