Under the hood temp of Stereomour

[shelby1420]

Hey all, I am thnking of using the Mundorf Silver and oil caps for the 3.3 in my Stereomour, only issue I can think of is they are rated at 55c, will this be ok or is the internal temp goning to get higher then this??

Rick

[Grainger49]

I am using a pair with my FP 2.  Be aware the FP 2 cathode resistors don't dissipate much heat and the Stereomour must radiate more. 

PJ can tell you what to expect.  But if I were you I would just put taller feet on it so it increases the cooling.

[Paul Joppa]

Several builders ran into problems with the original Jupiter beeswax capacitors in the SEX amp, which shorted when the wax melted. I believe they were rated 43C at full voltage, 54C at reduced voltage.* Very frustrating because they sounded really great until they failed! Generally I recommend 85C ratings, with 105C preferred.

* Jupiter has a replacement HT line now which is rated for 70C; I have not heard them but have also not heard of any problems.

[shelby1420]

I am using a pair with my FP 2.  Be aware the FP 2 cathode resistors don't dissipate much heat and the Stereomour must radiate more. 

PJ can tell you what to expect.  But if I were you I would just put taller feet on it so it increases the cooling.

I kinda figured as much, just curiou if anyone has tested the temp under the hood, I have them in my Paramounts and they have done well and sound friggin awesome, but seems to me this little baby gets hotter.................

[Grainger49]

I expect the Paramount cathode resistors dissipate more heat than the Stereomour cathode resistors.  Just my guess as it produces more power. 

I would think you are good.  BTW, I don't have any cooling to speak of on my FP 2.  I have never put feet on the base and, of course, it has no vents on the top cover.  The Mundorfs are beautiful sounding.

[shelby1420]

Thanks guys for the responses, just had another look at the Jupiter, very interesting, may have to give them a second look................using the "Solen 0.1uf / 1000VDC, S3ZQ Series,  Teflon Film & Tin Foil" in the coupling cap position and trying to mate something with it to work well together.......

[Grainger49]

I know that this is heresy, but...  try bypassing the Solen with a Kommie Kap 600V 0.22uF Teflon cap.  You must burn them in first[/u] to give them a fair shake.  Go for 300 hours.  That is 12 days, I do 14 just for good measure now.

Here is a link to a burn in method:

Fast Break In Post Link

This is an auction for 2, the same seller has four, why not buy four they are extremely cheap for how good they are???

http://cgi.ebay.com/0-22uF-600V-teflon-HI-END-capacitors-FT-3-Lot-2-/330435658361?pt=LH_DefaultDomain_0&hash=item4cef800279

Needless to say, I am not affiliated to the seller, I am just a KK Teflon junkie.

[shelby1420]

I know that this is heresy, but...  try bypassing the Solen with a Kommie Kap 600V 0.22uF Teflon cap.  You must burn them in first[/u] to give them a fair shake.  Go for 300 hours.  That is 12 days, I do 14 just for good measure now.

Here is a link to a burn in method:

Fast Break In Post Link

This is an auction for 2, the same seller has four, why not buy four they are extremely cheap for how good they are???

http://cgi.ebay.com/0-22uF-600V-teflon-HI-END-capacitors-FT-3-Lot-2-/330435658361?pt=LH_DefaultDomain_0&hash=item4cef800279

Needless to say, I am not affiliated to the seller, I am just a KK Teflon junkie.

Hey Granger, not knowing a whole lot about this kinda stuff, what would be the benefits of your suggestions??  I tend to lean to the warmer lusher type sound, would this do that for me?

[Grainger49]

The Teflon caps will clean up the high frequencies, make the top end clearer more detailed.  It doesn't affect the midrange as much and the bass much less.  

For the price it is worth a try.  Many like it.  

If you like a smooth warm sound try the Obbligato caps.  I put in 10uF 630V Polypropylene film in Oil as my parafeed caps when I upgraded the iron in my Paramours.  They are big suckers!  And don't forget to add in the shipping.  Shipping is a separate somewhere, I guess at checkout.

Obbligato PP Film in Oil:

http://www.diyhifisupply.com/catalog/35

[Thoburn]

I have had the new Jupiter caps running in my Stereomour for about a week. It runs 8 to 12 hours a day and they seem to be handling the heat. I do have 1/2 inch of old neopreme mouse pad holding the cabinet up. Mostly for isolation. I did not use the supplied feet.

[2wo]

I use the Obbligato copper 3.3uf cap in my SR-45 amp.

 http://www.diyhifisupply.com/node/85.

 Very good, and for the money can't be beat. Try them and maybe a Russian K40y for the coupling cap. Just might give you the sound you are looking for.

The Jupiter and Mundorf I think are great caps but at large values, expensive. I don't think the Obbligato gives up much if anything, Might be better.

I think the  coupling cap adds more of the "flavor" I have a set of the Mundorf silver to swap in for the K40s but it just doesn't seem pressing. ..John    

BTW. if you are thinking about spending a few hundred on caps, and are worried about heat. Buy a cheep temp probe and measure it

http://www.harborfreight.com/ac-dc-digital-multimeter-37772.html

[Paul Joppa]

I just realized that I have not mentioned the cooling slots on the Stereomour chassis plate. They are gradually going into most of our stuff, partly due to experience of the melting caps in the SEX kit.

Thoburn, it's not clear whether the whole base is sealed against the neoprene. If so, you really should raise the base enough to let some air flow in at the bottom. There should be more flow area available at the bottom that the total cooling slot area, to get the full benefit of cooler operation and longer component life. At a guess, I'd shoot for a minimum of twice the area.

[Thoburn]

The neopreme feet are 1 inch by 3/4 inch and are only at the corners. There is a lot open space for air to come in.

[shelby1420]

Well, decided after lots of humming and hawing I am gonna go with .1uf of the Solen Teflon film and Tin Foil for the coupling cap and 2.7uf Mundorf Silver/Gold/Oil for the output cap, think that should make a nice combo, once I have some hours on them I shall report back!!

Gettin real excited now......just bought myself some RCA Black Plates from the Tube Depot, rubbing hands anxiously!!!!

[shelby1420]

Update--
The Solens went in about 4-5 days ago noticed a huge difference right of the bat, greater dynamics, bass, depth and black like background!!!!  Today I put in the Mundorfs, I did notice a slight difference but not nearly as much as the immediate impact like the Solens......I suspect that the big change ( if any is to be had) will happen after about 3 -4 weeks of listening for the Mundorfs.......now waiting for the Black plate RCA to show up...........