2. amps-preamps
  3. 1146598194

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

Hello,
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 
undertow

Showing 6 responses by jeffreybehr

jeffreybehr's avatar
jeffreybehr
805 posts
 
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.

http://www.soniccraft.com/products/capacitors/film.htm

.
jeffreybehr's avatar
jeffreybehr
805 posts
 
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, http://www.audioasylum.com/scripts/tv.pl?forum=tweaks .
.
jeffreybehr's avatar
jeffreybehr
805 posts
 
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!
.
jeffreybehr's avatar
jeffreybehr
805 posts
 
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 http://gallery.audioasylum.com/cgi/upload.mpl .
.
jeffreybehr's avatar
jeffreybehr
805 posts
 
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.
.
jeffreybehr's avatar
jeffreybehr
805 posts
 
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.
.
More to discover