Dodd Preamp - Capacitor Upgrade Question

GregC · « **on:** 4 Jan 2010, 08:14 pm »

I have a Dodd Audio battery preamp that I love, and I was thinking of asking Gary to change the Sonicap Platinum capacitors to Mundorf capacitors. I love the sound of the preamp in its stock form (with the Sonicap Platinums) and I wonder if this is a case of "if ain't broke then don't fix it." However, as an audiophile (who is on the endless quest), I cannot help but ask myself if I can improve on an already exceptional preamp.

I have a few questions of people who are more knowledgeable in this area.

I am thinking about Mundorf Silver-Gold or Mundorf Silver-Gold-Oil capacitors and wonder about the sonic differences between them. Will Oil make the sonic character sound darker?

Is there a way to hook up a capacitor to something to break it in for 300 hours before using it in the preamp so I can avoid the painful break in process?

Is there a noticeable sonic improvement between Mundorf and the Sonicap Platinums that are currently in the preamp?

Thanks in advance for any advice in this area. I can easily be happy with the preamp as it stands, but wonder what Mundorfs can add to the magic.

ctviggen · « **Reply #1 on:** 4 Jan 2010, 08:38 pm »

Have you looked through that gigantic capacitor comparison thread? That may provide clues.

I have a Dodd Battery Preamp that I've not yet used (room still under construction), but I'm also interested in replies to this.

GregC · « **Reply #2 on:** 4 Jan 2010, 08:48 pm »

Bob,

I found the capacitor thread after I posted. So far I have not found how the Silver-Gold-Oils Mudorfs compare other than a mention that they are warmer than the Silver-Oils. Also, it would be great to hear from other Dodd owners with personal experience. I am one of the original 20 owners and the preamp is a foundation of my reference system.

Greg

jtwrace · « **Reply #3 on:** 4 Jan 2010, 08:52 pm »

Have you asked Gary his opinion?

GregC · « **Reply #4 on:** 4 Jan 2010, 08:57 pm »

I asked Gary and now I am soliciting feedback from the AC community. Gary did not have experience with the Silver-Gold-Oil capacitors but he has some customers who are happy with the Silver-Gold capacitors.

jtwrace · « **Reply #5 on:** 4 Jan 2010, 08:59 pm »

Quote from: GregC on 4 Jan 2010, 08:57 pm

I asked Gary and now I am soliciting feedback from the AC community. Gary did not have experience with the Silver-Gold-Oil capacitors but he has some customers who are happy with the Silver-Gold capacitors.

Cool. I'll be following....

jtwrace · « **Reply #6 on:** 19 Jan 2010, 07:39 pm »

any updates?

Danny Richie · « **Reply #7 on:** 19 Jan 2010, 07:53 pm »

Typically the Silver/Gold/oil caps tend to soften or truncate transient peaks.

I have had some experience with them in a loudspeaker circuit comparing those Mundorf's to Sonicaps by-passed with Platinums. The Mundorf's gave up a lot of resolution in the top end and the sound stage was much more two dimensional compared to the Sonicaps. Later adding Sonicap Platinum by-pass caps to the Mundorf's brought them around and made it closer.

Clearly the Mundorf's (that type anyway) color the sound, but do so in a way that some people like with their systems.

I'd be more inclined to try the Mundorf's in place of the 3.3uF Sonicaps and leave the Platinum by-pass caps. A 3.3uF is pretty large though and I don't know how easily it will fit.

bluemike · « **Reply #8 on:** 19 Jan 2010, 08:10 pm »

I have a pair of Dodd Amps and looking for a cap change after alot of reseach i'm going with the Audiocap Pcu
for preamps I would go vcaps if those are too spendy check out the relcap or multicap lineup

jtwrace · « **Reply #9 on:** 19 Jan 2010, 11:24 pm »

Quote from: bluemike on 19 Jan 2010, 08:10 pm

I have a pair of Dodd Amps and looking for a cap change after alot of reseach i'm going with the Audiocap Pcu
for preamps I would go vcaps if those are too spendy check out the relcap or multicap lineup

Let us know how it goes. Are they 120's?

bluemike · « **Reply #10 on:** 20 Jan 2010, 02:38 am »

Quote from: jtwrace on 19 Jan 2010, 11:24 pm

Let us know how it goes. Are they 120's?

yes they are ..I know of another poster who's ears I trust that went with the Audiocap pcu and was very happy with them - He actually preferred these over the sonicaps plats in his dodd amps
Will report how they sound once installed

Anyone else heard these caps in audio equipment and care to comment ?

RPM123 · « **Reply #11 on:** 20 Jan 2010, 04:14 pm »

"However, as an audiophile (who is on the endless quest), I cannot help but ask myself if I can improve on an already exceptional preamp."

Try swapping tubes instead... it's a lot easier!

jtwrace · « **Reply #12 on:** 20 Jan 2010, 04:19 pm »

Quote from: bluemike on 20 Jan 2010, 02:38 am

yes they are ..I know of another poster who's ears I trust that went with the Audiocap pcu and was very happy with them - He actually preferred these over the sonicaps plats in his dodd amps
Will report how they sound once installed

Anyone else heard these caps in audio equipment and care to comment ?

What generation?

GregC · « **Reply #13 on:** 20 Jan 2010, 05:47 pm »

Quote from: RPM123 on 20 Jan 2010, 04:14 pm

"However, as an audiophile (who is on the endless quest), I cannot help but ask myself if I can improve on an already exceptional preamp."

Try swapping tubes instead... it's a lot easier!

I have tried at least 8 different sets of tubes until I decided on my reference 1965 White Label USA 7308 Amperex tubes (with a set of early 1960's Telefunken E88CC tubes as my backups). I agree that tube swapping is the best place to start. I love the preamp "as-is" and I hesitate to change it for the sake of change, especially if Mundorfs color the sound. The pre-amp is extremely neutral and resolving and I prefer to not add any colorations.

bluemike · « **Reply #14 on:** 22 Jan 2010, 01:32 pm »

Quote from: jtwrace on 20 Jan 2010, 04:19 pm

What generation?

version 2 with upgraded finish these really look the part

NagysAudio · « **Reply #15 on:** 26 Jan 2010, 12:11 am »

You should really try the ERO MKT1822 capacitors. They work great as coupling/filter caps and are some of the best sounding caps on the market.

GregC · « **Reply #16 on:** 26 Jan 2010, 12:17 am »

Quote from: NagysAudio on 26 Jan 2010, 12:11 am

You should really try the ERO MKT1822 capacitors. They work great as coupling/filter caps and are some of the best sounding caps on the market.

Thanks for the tip. On the Humble Homemade HiFi it only rated the cap at 6+.

NagysAudio · « **Reply #17 on:** 26 Jan 2010, 12:20 am »

He rated the Vishay MKT1822 a 6+, not the ERO version. There's a significant difference between the two, I have used them both extensively in my designs. Problem is, is that ERO no longer makes caps, so you can only get them on eBay as new old stock...

GregC · « **Reply #18 on:** 26 Jan 2010, 12:53 am »

Quote from: NagysAudio on 26 Jan 2010, 12:20 am

He rated the Vishay MKT1822 a 6+, not the ERO version. There's a significant difference between the two, I have used them both extensively in my designs. Problem is, is that ERO no longer makes caps, so you can only get them on eBay as new old stock...

That makes perfect sense. I would just need to find a pair of 3.3 MFD or else run them in parallel.

NagysAudio · « **Reply #19 on:** 26 Jan 2010, 01:08 am »

That might be a bit difficult, there's not that much room inside that preamp, as you might have to parallel 3 of them to get that particular value. I also like the Jantzen Z-Silver caps and they do have the standard 3.3 uF values...