Preamp Caps?Auricap,Mundorf, Hovland, jensen,solen

I have a preamp with only 2 Signal caps directly in front of two tubes shot right out to the amps, extreme simplicity and excellent sound. This is the first preamp that came stock with Auricap's I have owned or heard, most in the past have always had Multicaps, Kimber caps in my previous pre's. I can say I think the Auricaps are quite a bit better but not that expensive or the end all-be all that I understand. Now I have had some crossovers and a Preamp with Solen fastcaps in it, and they are the best in Bass I have heard out of all of them, not that it makes them superior just an observation. I have also purchased Jensens oil and put them in Tube equipment in the past, not bad but did not blow my doors off.. And Finally Hovlands, not my Cup if you know what I mean, I found them the most expensive and the least impressive, could be the mix of component used in, but whatever too dry for me. Mundorf is a little newer on the scene to me and I thought the Hovlands were pretty obscene in cost, however these are the new Cost and hype leaders from what I can tell today. I am considering trying the Mundorf Silver in oil supreme caps at no small cost to see if they are gonna create more magic than the Auricaps. . What is the character of this cap? I want very 3d and open yet still have some intimate warmth and very powerful bass. Is this a cap worth venturing over all the other explanations I left here? Needs a liquid sound, and get that fairly deep bass solen seems to be capable of for only a couple dollars a cap, cause I do not want to soften the already slightly soft Tube bass. Thanks to all that know about this tweaking and expereance with these caps . . Again its only 2 Caps, very easy to install so its hard to keep my hands off, but do not want to go backwards or waste the cause if its not gonna be very significant in this specific application, Anybody know of any good tube equipment or preamps using these mundorf super caps? By the way my tubes are Mullards NOS. Preamp manufacture would seem to be irrelevant here and yes I am pretty dang happy with the sound for the money already, but there is always more right 
I've used Mundorf Supreme S/Os as couplers in a couple pieces of equipment. Altho I'm no GEA who can hear all kinds of subtle differences, I found the MSS/Os to be rather clean and detailed (but never edgy) yet a tad warm sounding. You may well love their sound.

That said, I now use Cardas Golden Ratio as my 'affordable' cap and SoniCap Platinum as my best-money-can-buy cap. The CGRs are more tonally neutral than the MSS/O while not losing any of music's harmonic richness. The SPs are even cleaner and quicker than the CGRs. Since you need only 2 caps, do consider the SCPs. If you need a large value, say, more than a couple microFarads, you might consider a large CGR bypassed with a SCP.

The V-Cap Teflon is one of the coupling caps in existance. There really aren't any paper and oil parts that challenge it. Paper and oil is nice, but in nearly all of them there is a slightly shelved high frequency character (mind you- not a rolloff) that causes them to have an overly delicate character. Nice for a lot of things but annoying if you play the complete range of music on your system.

Good Teflons like the V-Cap are also smooth, but actually have more detail without the price of a bright coloration. Certainly they are more detailed than paper and oils with considerably more neutrality. Paper and Oil caps can develop electrical leakage over time that can damage other parts- this is something that most other dielectrics including Teflon don't tend to do!

If you want a musical instrument (but not a musical reproducer), paper and oils will be a good choice. If you actually want music itself, you'll have to go with Teflon, and the V-Cap is one of the best out there.
Under, YW.

What cap value is there now? Is there a grounding resistor following the cap? What value? What's the input impedance of the poweramp you're driving?

I love your "...there is always more right." You are SO correct! This is definitely NOT a 'if it's not broke, don't fix it' hobby.

You might Search for mentions of these caps on Audio Asylums' tweakers asylum, .
Atmasphere, Yeah the V-cap forgot about that bad boy, could be a good choice and actually a little better pricing maybe, thanks.

Jeffreybehr,, There is Qty.2 (2.2 mF) 200 volt auricaps in there, not huge, pretty common value and easy to get it seems... Umm, Resistor... Not sure? Did not see anything in the way of resistors right there, but have some for setting the impeadance on the MC phono section in another part of the preamp... I believe the Output impeadance of the PReamp is 1000 ohm(yeah a little high I understand) and the amps are of solid state breed at 10,000 ohm input... I was originally concerned myself with Gain because its only exacly 10 times difference between the 2 and have heard the Times 10x rule, but I have had excellent results and never could ask for more gain so taking the risk paid off it seems even with the slightly high output impeadance. I have no problems in the functioning of the system at all, so new caps are just going overboard to see how much juice we can squeeze out of this rock.
Edit: Opps nevermind V-cap is out of control cost, I did not think anybody had a cap that high in cost at such low values, okay... I don't know how big they are either, might not have any kind of space for them especially since I would probably have to use (4) 1 mF stacked up and that would cost more than most preamps...

Atmasphere, Yeah the V-cap forgot about that bad boy, could be a good choice and actually a little better pricing maybe, thanks.

Jeffreybehr,, There is Qty.2 (2.2 mF) 200 volt auricaps in there, not huge, pretty common value and easy to get it seems... Umm, Resistor... Not sure? Did not see anything in the way of resistors right there, but have some for setting the impeadance on the MC phono section in another part of the preamp... I believe the Output impeadance of the PReamp is 1000 ohm(yeah a little high I understand) and the amps are of solid state breed at 10,000 ohm input... I was originally concerned myself with Gain because its only exacly 10 times difference between the 2 and have heard the Times 10x rule, but I have had excellent results and never could ask for more gain so taking the risk paid off it seems even with the slightly high output impeadance. I have no problems in the functioning of the system at all, so new caps are just going overboard to see how much juice we can squeeze out of this rock.
V-Caps are actually smaller than the equivalent values in polystyrene. You might check the dimensions.

If you can't afford the V-Caps, consider the Rel-Cap Teflons.
Are the cardas not teflon? Well for affording them I don't have that issue as much as diminishing returns at some point, I have a fishey feeling they would not be double the performance of some of these caps costing half the price already at 100 bucks a pop . . But again I could see benefits, but honestly for that cost in a Capacitor I would absolutly have to hear an A-B test with identicle equipment head to head with another good Cap to consider blowing that kinda money on a fairly basic and not super criticle but important upgrade move. And I know I won't get that A-B and never may know, but yeah that is very pricey for the risk I am willing to experement with here.
How about these? PPT Theta AudioCap, look pretty good too.

Most of these types only come in 2.0 uF so would I need to buy 2 of these and then use a .22 uF in parallel?

What is the best way to attach the cap to the board physically, Silicon, Double sided tape, Blue tac, or one sided weather stripping to just set the cap on to reduce vibration?

Right now the caps in the unit do not have anything under them, not sure if I should correct this or not when going in there to do this.
1. The preamp's output impedance is determined by the nature of the circuitry.
2. V-Cap TFTFs (teflon-film, tin foil) are fine-sounding caps and arguably as good-sounding as money can buy, and so are SoniCap Platinums (which also are made with teflon film, in this case a proprietary teflon-alloy) and which also are arguably as good-sounding as money can buy. SCPs are significantly less expensive.
3. I understand the CardasGR uses 'propylene and teflon film.
4. The high-pass filter established by your output couplers and amp input impedance is about 7 Hertz, rather high WITHOUT an output-load resistor in the preamp, and I'd be very suprised if there isn't one. (If there is one, the filter point goes UP.) If you intend to keep this amp and if you'd like to have more-solid-sounding bass, I'd move that filter down at least an octave by about-doubling the value of the caps. I believe I'd build a composite cap and start with a MultiCap RTX ('styrene) of 3/200 ($42), a 1/600 Cardas GR, and then a 0.1/600 SoniCap Platinum ($29). Another combination that has potential and is less expensive would be a large SoniCap-1, say a 6.8/200 for $14, with as large a Cargas GR as you choose to afford, say a 0.47 for $30, in parallel. This gains even higher-quality bass via a lower filter point--in this case just over 2Hz ignoring the preamp's output-gounding resistor.
5. I mount caps with 3M double-sided plasic-foam tape. Here's a pic...

...of the couplers in my ASL 'Canes, showing a pair of CGRs 'taped' together and also to the ceiling of the amp.
6. Caps break-in just as about-all other 'passive' devices; I recommend AT LEAST 50 hours of high-level music for the 'propylenes, 100 hours for 'styrenes, and 500 hours for teflon caps, before you listen critically.

BTW I do put my money where my mouth is; I used SoniCap Platinums in the 1st coupling position and Cardas GRs in the 2nd in these Hurricanes, in spite of having to buy 4 SCPs and 16 CGRs!
Jeffrey, I really appreciate your time!
I am not a pro and I am finding now this might be super effective upgrade because:

#1- I threw in the new mullard tubes last night after I received them, Wow night and day! Big difference in bass and space, very smooth and warm. So obviously the 2 Capacitors hooked to those 2 tubes going straight out the RCA's will be fairly effective to the final sound, Kinda excited now about this upgrade just to see.. (or hear)

#2- I emailed the companies link you gave me, they replied below:
--The Auricaps are not bad, but there are better caps at a price. Either,
the Cardas or the Mundorf S/O would do better. However, you are
looking for more bass first. I would start by going to a 3.3uF cap.
This will slow thing just a tad, so you will want to bypass with a
0.1uF. My selection would be based on your budget. At the top, a S/O
3.3 bypassed with a Sonicap Platinum 0.1uF. At the bottom, a Sonicap
3.3 bypassed with a Cardas 0.1uF.

Remember, a single pair of caps can not make your we
should never look for it to.


So Know I gotta be honest, although simple, Stacking and accidently burning caps together and fitting them correctly might be beyond the scope of my original comfort doing it myself. .Plus you give a bit different approch than they do in what to use value wise and all that.. For the few dollars in labor who would do this the right way to send it out? I hate shipping for this, but I live in Illinois, anybody got a suggestion.
Under, e-mail me at jeffreybehr(at)cox(dot)net. I'm in Phoenix, have done cap- and resistor-upgrade mods for others, and I'd do this for you for a nominal fee...that would turn out to be maybe a quarter of what the pros would charge you. Also, I can help, with Jeff Glowacki, to resolve you capacitor choices.

I agree heartily with Jeff about changing the sound of a component by changing caps. If you LOVE this preamp, you can make it better, but you can't change its basic character simply by changing coupling caps.

For that pic that didn't display, and lots more, go to .
I am using a very small value, .01uf teflon cap to bypass a large 5.0 uf metalized poly.

After months on end of burn in. I will confirm that the teflon cap has higher resolution, smooth-almost lush midrange and not bright.

Compared to MIT RTX, the teflon is less bright, yet higher in resolution and clearer. Very rare and desireable traits indeed.
Update, I have gone back to RTX .22UF bypass cap in place of teflon. In my tube pre-amp- (the smooth midrange balance and ultra black background in the highs that seams to be a hallmark of teflon)was just to over bearing to live with. I want to hear the midrange that the tubes deliver. Not the smooth midrange of Teflon. Teflon would probably be the cap of choice in solid state. But for tubes...just didn't work out for me. I know others have also, ultimately felt that Teflon sounds that way to them. Just to smooth....IMO.

One characteristic of the BEST-sounding 'passive' devices is that they're detailed--they pass all (or nearly all) of the information WITHOUT adding an edge to the sound that some of us think is more detail. For instance, the sounds of live trumpets and trombones when blown hard have an edge to them, and sometimes they're VERY sharp sounding. When heard live and unamplified, you know you're hearing 'detail' without edginess. Less-than-ideal passive (and active, too) components add an edginess to the sound that's unattractive, and too much of it gets ugly quickly. 'Smoothness' is detail without edginess; I love it and it's my principal sonic goal when modifying equipment*. What I call 5-star components and parts are smooth AND detailed--and tonally neutral, too, without losing any of music's essential fundamentals and harmonics.

* I truly am NOT a GEA; I have to work hard at hearing differences that for me are subtle. The GEAs hear and talk about all kinds of differences that I can't hear.
I like to hear the edge that is present in many of the rock recordings I listen to. Smooth, when the sound should be sharp, with high resolution in the midrange is just another form of coloration.
I've spent some time reading internet posts regarding opinions on Teflon capacitors. A common word that comes up is "midrange". I'm convinced that the weakness of Teflon, is that it has a very prominent signature in this frequency range. The midrange is where the music lives. I want to hear the music as on the recording. Sugar coating and enhancing the power of this range may work well with panel type speakers, but with cones its like a lead weight.
I've tried using the TFTF V-caps in a few different bypass positions using different bypass values(preamp couplers, speaker crossovers), and ultimately have removed them. Initially the resolution and air that the teflon caps add is impressive. However, they become to prominent over time and have a signature that is easy to recognize. Even after the 400 plus hours of break in. Personally I would only use them if I could afford a single teflon cap in the value required. I'm using the Mundorf Supreme Silver in Oils as couplers in my preamp. While they don't have the same resolution as the teflon caps, they come pretty close, and sound tonally even from top to bottom.
I replaced MIT multicaps with the VH paper in oil caps in My DAC. I use the VH teflon bypass cap with the paper in oil. I tried a vintage Sprague paper in oil bypass but it had too much treble energy for my system. The VH caps are expensive (about $100.00) per side but they deliver a more musical presentation. These are a great upgrade for the Audio Logic DAC.
Tom monro,

Have you considered trying the OIMP(Oil impregnated) V-caps in your preamp outputs to compare to the Mundorfs you currently have in there? That would be an interesting comparison.
I'll chime on here with my experiences and mind you this was in a coupling position on my amp.
I have had Auricap, Mundorf supreme, Mundorf Silver/oil, and Vcap. I have had hovlands and Cardas in other amps too but can't compare in this case.
I hate to use the usual audiophile jargon so I will just convey which were the best and most natural sounding. To me, I tend to prefer what sounds natural and real, you know, what real live unamplified music sounds like.
In my amp the auricaps although better than the stock solens were the poorest of the lot. While the Mundorf S/O's sounded nice, for some reason, I can detect silver in the signal path in my system and don't like it. It sounds un natural. I feel that for silver to work, the circuit has to be designed for silver.
The Mundorf supremes are quite good and excellent for the money. I loved the Audio note Coppers but they are massive (1uf) and would have to modify my amp to make them fit. And that is what I would have done if not for the Vcaps. The Audio notes are great but the Vcaps are amazing. How? it has already been said above.
So my advice is to splurge on the Vcaps. If they cost too much, try the oimps or the sonicaps as suggested above. Or if on a budget, the Cardas or Mundorf. There is a cap shootout on the Vcap website. Keep in mind that your preferences may not be the same of that author's. He rates the mundorf silvers above the silver/golds (which I have not heard) and the supremes. I did not care that much for the silvers. As they say YYMV
Sherod, I went back to OIMPs bypassed with TFTFs in my deHavilland UV preamp about five months ago. I'm now using 2.7uf OIMPs bypassed with .22uf TFTFs. This combination blends seamlessly, and for the most part sounds like an all TFTF v-cap. That said, I did not have good luck with the 3.3uf OIMPs that I originally bought a few years ago. For some reason the 3.3uf OIMPs were much softer and slower sounding compared to the TFTFs and the tonal contrast between the two could be easily heard. I changed over to a single pair of 2.7uf Mundorf SIOs. I liked the Mundorfs for their resolution. However, at times the Mundorfs could sound lean and light on the bottom end, and a little matter of fact sounding. This was the main reason I gave the v-caps another try. In my system the OIMP/TFTF combination have a more expansive soundstage, the low end is solid and has some weight to it, tone is slightly lush, yet the detail and transparency is excellent.
Very interesting Tom. I am assuming that the original cap in your preamp was a 3.3 uf value. I'm curious why you picked a 2.7 uf OIMP with a .22 uf Teflon bypass. Is this because it matched the original cap value better? I'm curious what the input impedance of your amp is as well. Is it tube also? I currently have a 4.0 uf OIMP in my preamp output that replaced a similar value Hovland cap. The OIMP after break-in definitely lets through more information, but to my ears offers a little bit too much full-bodied sound. Another gentleman who does quite a bit of modifications and is familiar with the V-caps suggested that I bypass with a .1 uf V-cap Teflon. I did that and currently have about 315 hours on the bypass, and although the tone is a little less full-bodied, the overall sound is a little too tilted up for my tastes. I'm wondering if maybe I should go with a smaller OIMP as you did and try the Teflon bypass again on it. HMMMMM. very interesting.
The original caps in my UV were a paralleled pair of 1uf Russian PIOs and 1.5uf Auricaps for a total of 2.5uf per channel. What you are describing with your 4uf OIMP and .1 TFTF is similar to my experience with the 3.3uf OIMP. I tried a .01, .1, and .22 TFTF bypass with the 3.3uf OIMP, and although the .22 worked best, there was still a discernable cutoff point where I could hear the softer OIMP take over. And, yes the 3.3uf was a little to heavy handed in the bass, so that's why I gave the 2.7uf a try. The bass is more proportional, and overall the 2.7uf OIMP is quicker and more transparent. These qualities allow the TFTF to blend in better. Having tried both the .01 and .1 TFTFs, the .22 TFTF is not as tilted up on top, and has more body in the upper registers. The input impedance of my last two amps is 100k ohms, so the smaller value caps work fine. The deHavilland UV is a tube preamp.
I would like to comment that the above posters are going about selecting capacitors the "right" way. That is, to experiment with your specific piece of equipment and letting your own ears be the judge. There is no right or wrong in capacitor selection, it is a sonic recipe. Often a combination of two different caps.
Thank you Tom, for your detailed reply. I have tube monoblock amps that also have an input impedance of 100K ohms. As I understand the formula for determining the preamp output cap value, the lower the cap value, the lower the bass -3db roll-off point, correct? Also, Tom, when you put in the OIMP 2.7 uf caps, did you put them in alone and break them in before you put on the Teflon bypass caps or did you put everything in together and go through the long break-in period?
Well, here's my situation. I recently replaced two 4.0uf Hovland Musicaps for equal value V-Cap OIMP(oil impregnated) caps in the output of my preamp. After about 400 hours of break-in( ample time, I would imagine) I determined that the OIMP V-caps were superior in most respects, particularly in allowing more information through, especially in the highs. However, in my extended listening sessions, I've found that the OIMP has a slight sonic signature of a little extra warmth, fullness and perhaps a roundness or softness, if you will. This signature is easy to live with because it is euphonic and actually adds a texture or coloration that enhances rather that detracts from the listening experience. However, being the anal perfectionist that I am and wanting a purer and more neutral characteristic of tones and timbres, I decided to bypass the OIMP with a smaller( .1uf) V-cap teflon. After going through the unbearable time of break-in for the Teflons( I'm currently approaching 400 hours) I have concluded that although the teflon bypass caps do indeed take some of the over-warmthness away and nicely extend both frequency extremes, the overall sound has a shelved-effect. It's difficult to explain this phenomena, but it's like a tilting up of the frequency where all the frequencies seem a little thinner and elevated. This isn't a too bright sound, just an over-elevation of tonal balance. I'm now frustrated because I thought that maybe I had hit the ultimate synergy with the V-Cap combo. I haven't given up just yet, though. I'm thinking that maybe, the .1uf Teflon value might be either too large or too small. I'm not sure because this cap evaluation is relatively new to me. So maybe other members might be able to make some suggestions. My tube monoblock amps have an input impedance of 100K ohms and the preamp has roughly 600 ohms output.

Though my experience with substitute couplers is not extensive, in the course of web searches I came across several reviewers with similar observations of discontinuous treble as a result of bypassing non-teflon couplers with small teflon caps.

I've heard substantial improvement with Mundorf Silver/Gold in place of REL styrene in my tube pre, and V-Cap TFTF in place of BAT OIP in my tube amp. In another line-level component I'm about to replace Hovland Musicap with Mundorf Silver/Gold. My listening experience with the V-Cap vs. BAT oilers reveals that at this level teflon is more precise, revealing & linear across the entire frequency range, with less swelling in the bass and midrange.

The Silver/Gold & V-Cap TFTF are both great caps!
Sherod: "As I understand the formula for determining the preamp output cap value, the lower the cap value, the lower the bass -3db roll-off point..." No, Sherod, that's backwards. The formula for determining the -3dB ("filter") point of a hi-pass cap is F = 159155/RC where F = frequency in Hertz, R = resistance in Ohms, and C = capacitance in microFarads. Since the F is in the denominator of the fraction, a larger C causes F to decrease. So higher-value cap = lower filter point.
Thank you everyone for your input. I am determined to get the right combo of values using these V-caps for my preamp outputs. I know it's a matter of trial and error, but the costs of these V-caps makes it a very expensive trial. I was hoping for some input from other V-cap users, particularly for the output cap in their tube preamp. I'll try to keep you posted on the developments.
Wow! A lot can happen in a couple of years. In the meantime, a new "kid on the block", Claritycap MR( stands for "minimum resonance") has gone into the outputs of my preamp and they are an amazing cap. So far, the best cap that sounds (or should I really say it sounds like "no cap") more neutral and transparent,along with incredible dynamics, than any other cap, including those mentioned, in my preamp. This cap has taken my preamp to new heights.
Ha, yeah wow... totally dug this one up from the grave! Big changes over the years, now I totally tear apart and do everything myself, far simpler and way cheaper once you have some skill's and tools to do it, oh and ears that can find the right mix!

Yes best cap and newest over these spoken about back then are in fact the Clarity cap MR's as Sherod points out... Best cap for the money available today. Duelunds are great too, much better than mundorfs, but pretty pricey and very hard to get a hold of.
It was your post in Audiocircle, describing the mods you did to a Jolida phono preamp that convinced me to try out these new Claritycap MR caps. I had read in a few chat forums where these caps were being tried successfully in speaker cross-overs, but your post was the first where someone actually tried these new caps in an electronic component as a full-range capacitor. I want to thank you for introducing this cap to me. It has brought my preamp to a whole new level of listening enjoyment.
No problem, yeah they are also nice because they have a high voltage rating to be used universally to and extent over some of the exotic caps only good for crossovers.