Reply with quote #16
As I like to voice each kit I build, I take a lot of time experimenting with a whole range of caps, from polyesters, paper-in-oils, polystyrenes, polypropylenes and teflons. I try new modern caps as well as NOS or vintage caps, including some Russian caps. As I already have quite a lot of different caps on-hand from previous tries on previous kits, its a relatively easy thing to do for me. In the MP, I initially replaced the 1uf caps with Phillips 1uf 400v MKT orange dipped polyester caps as this was the only 1uf caps I had with me at the time. Yes, polyester... (They are really great polyesters...) I replaced the 0.1uf caps with used Mundorf MCap Supreme Silver Gold 0.1uf 1000V caps that were given to me by a friend who had upgraded from them. And the 3.3uf caps were replaced by used 2.72uf 200V Cornell Dubilier polypropylene caps (old CDE series MCR2W2P72K) that I also salvaged. This was a very good combination actually, resulting in a huge change to the sound character. No longer dark and muddy (to my ears)... just open, airy, wonderful mids and highs, and rich sounding with a certain roundness to the sound (is that the 300B sweetness?) and I was happy with them for a couple of weeks while I placed some orders for other caps to further voice with. I could have stopped here and been happy, but I had the feeling that things could be improved further. At this point, the cost to get this result is not really that much. I then replaced the Phillips 1uf and CDE 2.72uf caps with 1uf and 3.3uf Jantzen Superior Z-caps respectively, but have since reverted to the 2.72uf CDE caps, and am now auditioning NOS 1uf 400V Sprague Orange Drop caps (yes, the NOS Spragues, not CDE or SBE). Believe it or not, the Sprague 1uf was better (in this application) than the Jantzen 1uf. I could hear better environmental and spatial acoustics, the mids and highs are really clear and the sense of resolution is there, but it is fascinatingly smooth and not harsh . Perhaps I need to break-in the Jantzens more on my dummy-load "burn-in rig". The Jantzen 1uf and 3.3uf caps were nice and smooth, no harshness to the upper mids and highs, but I get the feel that there is a bit of a lack of resolution (maybe its a sense of being too smooth?) but after a further 10 days, things began to sound not as clear and I felt a loss of transparency, a bit of darkness and veiling of the sound. I had done a 80-hour burn-in on these new caps on a dummy load prior to installing them, but I guess they may need more breaking-in as I have found that caps sometimes go through a "sick period" before getting better again, and will do so and test them again later. I hope that they turn out better than the CDE 2.72uf because the CDEs are no longer available. The CDE 2.72uf are really good. The clarity and transparency was back. I had never heard of these caps previously and they look very ordinary and generic as polypropylenes. The Mundorf 0.1uf was replaced with Audyn True Copper Max 0.22uf 630V caps that I also previously bought and already had. This made the largest difference among all the cap swaps so far. I love the Audyn True Copper Max series. They are certainly very expensive to me, but I think they are quite possibly the best sounding caps without getting to Duelands, Jupiters, Jensen Silvers, etc. territory. Bigger soundstage than the Mundorf, deeper and more 3-D like, and the timbre and life-like sound character to acoustic instruments and vocals is really obvious. When I first made this swap and played it, the sound character was really different from the Mundorf, so I will say that the change is quite noticeable immediately. The sound is richer (denser or meatier?), but not warmer or fuzzy in any way, it is more open and transparent, like you can feel the music breathe. Of course, I made each cap swap one set at a time, to listen for differences, and waited at least 4 days to a week before deciding if I will make a change. I am still burning-in some Russian FT-3 teflons, K74-1 polystyrenes, K40Y-9 PIOs, and also Sprague PIOs. Most of these I already had as I mentioned. One interesting thing I have observed previously is that often it is good to not stick to only one type or brand of caps within the same chassis, and you often get better results through this mixing of types and brands (like a synergy of some sort). I will give an unusual example when I write about the changes I made to the caps in the SOB. I will eventually settle down on a set of caps, but it may take some time. I spent 2 to 3 months on my previous kit amp voicing different coupling caps until I was satisfied. There is no such thing as only one type or brand of cap that is universally going to be the best in all applications, in preamps or amps. A mix of affordable and expensive, and modern and NOS, strangely works better, I have found. Mel
Reply with quote #17
What about the many other sound altering aspects in the amp? I miss this part of the picture in this discussion. Too much importance on coupling caps only…or at least without considering the bigger picture which would put everything in better relation to each other. Lest we forget an amp uses the power of the psu to increase the amplitude of a small signal, turns a small electric current into a large current. It operates from stage to stage, input to output, each stage being connected to the rails of the psu and there is no such thing like a current flowing “right through the amp” from input to output with less important parts (between positive rail to ground connection) and more important parts in the so called “signal path”.
No doubt the quality of coupling caps is very important but looking at the amp as a whole and its connection to the rest of the system is equally important. Simple Mundorf Supreme caps sound pretty neutral and are still reasonably priced. I tried Multicap, AN, some Beewax caps (forgot the name, but sounded a little too bright), some of these highly recommended green Russian caps (which sounded too dull for my feeling) and some other stuff. The ASC with vegetable oil bypassed with some Mundorf sounded absolutely great in the TS phono (not used as coupling caps). I couldn’t stop listening, especially to solo guitar and piano.
But I must say that the influence of the filament psu on DHTs or even the transformers’ radiation has often a much bigger effect on the sound than any cap change ever had in my experience. The smaller the signal current, the bigger the influence of the filament psu on the sound. So it’s not such a big issue with TS 300B amps which operate at 100/125mA.The right choice of diodes, especially in the HV psu, cannot be underestimated. And the biggest sound altering changes I have achieved was with adjusting the NFB loop to the speakers. I guess that would also be beneficial for 600ohm headphones if the MP is only used as a headphone amp or if this option is switchable.
Here is some more food for thoughts. It is advanced but there might be some people on this forum who like to read about this kind of stuff.
Reply with quote #18
Would caps like this be any better? I recall the kit being 400V however.
I will build it with stock caps, but if anyone has some links I would be appreciative. Attached Images
Reply with quote #19
Well now I'm in heaven.
2 quick questions - what volumes should I have for my digital signal source (chromecast-toslink-schiit modi multibit- masterpiece). DAC has 2V output - should I keep digital signal lower to make Masterpiece do more of the amplification?
Secondly, I have a ground loop hum, very very faint, coming from my Project HaiFI phono amp - any tips? No hum from the DAC.
This is amazing and I'm so proud that it works!!!! Attached Images
Reply with quote #20
Your tonearm wiring is right next to your power amp. The first thing I'd try is to move the turntable to the end of the equipment row. Put the preamp next to it and the power amp next to the pre. If that doesn't work, place the turntable on its own shelf.
Reply with quote #21
Yeah I realised that swapped the pre/power. I'll see if I can get TT to edge...currently the bracket blocks it. Might try to find it's own shelf.
Reply with quote #22
Wolfgang, thanks as always, for sharing your thoughts... I think the reason many folks (even us DIY folks) experiment with coupling caps is because its "safe" to just substitute and listen to its effects, without changing anything to the original design or circuit of the kits.
As I mentioned in my post, not everyone may be able to hear the differences as this is very much dependent on their other system components, but in my system, the differences are pretty obvious and easily heard not just by me but by other members of my family (who are not hifi enthusiasts). Perhaps my speakers, which are Tekton Design OB Sigma speakers, make these changes easy to spot. But, I credit the fact that the MP and SOB are both very revealing and transparent hardware to begin with, so I think it is worth the effort to make these relatively easy substitutions to the caps. Would love to know of the various changes you have made to the PSU in the MP or SOB or any of the other current model TS amps. The link you posted to the article by Richard Sears is very interesting and the High Voltage Shunt Regulated Supply Kits by K&R Audio look like they could be put to the same effect. As many of us here would not be sufficiently knowledgeable to implement any of these CCR kits (or anything else) into the line stages or input stages of the MP or SOB, do you have any details to share of what you have done and how you did it so we too could join you in these experiments? Mel
Reply with quote #23
Originally Posted by
Gints Would caps like this be any better? I recall the kit being 400V however. I will build it with stock caps, but if anyone has some links I would be appreciative. Hi Gints, I would not use these polypropylene safety caps, they are not made for these signal coupling applications. You can check out http://www.mouser.com, or http://www.rs-online.com, and also Ebay. Google to check out and compare prices. If you want to look at Jantzen caps, which I feel are well performing and fairly priced audiophile capacitors, I got some of mine here: http://audio-hi.fi/en/capacitors_film_capacitors-c-9_10.html?filter_id=15&sort=20a If you want to have some point of reference of people who have done some of these tests, you can start with: http://www.humblehomemadehifi.com/Cap.html http://www.enjoythemusic.com/diy/0708/capacitor1.htm http://www.laventure.net/tourist/caps.htm Do keep in mind that these are personal opinions and evaluations, and may not even have been tested in the role of signal coupling caps. But they do provide a starting point for you to get an idea and perhaps figure out what you want to try. My own broad views are already stated in my previous post. Hope this helps for a start. Mel
Reply with quote #24
Digital sources should always have software volume maxed at 100%
Reply with quote #25
I went with Mundorf SGO's. Figured I was only going to do this once so why not.............