Suggestions for cap replacement - Silver Iris x-over

gooberdude · « **on:** 14 Aug 2007, 04:57 am »

I'm about to buy new components for the x-over on the Hawthorne Silver Iris'...anyone have any suggestions?

Alpha Core foil inductors will total $55, and i'd like to stay around $100 for the caps.

2 - 10 uF caps & 2 - 6.8uF caps are needed. 400VDC. I'd like to run all Auricaps but dunno...

In the range of better caps, is it OK to assume that the level of clarity & transparency are of a certain benchmark, just leaving tone as a deciding factor??

My tastes run toward the warm and lush side, these drivers have speed and transparency already...and i'll probably stay with an SS amp for awhile.

I inserted Mills MRA-12 resistors in place of the stock Dayton's - what a difference.

Soniccraft.com is the only vendor i'm familiar with. suggestions welcome.

markC · « **Reply #1 on:** 15 Aug 2007, 09:18 pm »

If you want warm and lush, probably paper & oil. No experience with 'em, but have researched a lot on caps. Mundorf silver & oil are suposed to be very good, but pricey. I personally like sonicaps over the Auri's. Both the Mundorf and the sonicaps are available from sonicraft.
As for the inductors, you might want to be carefull with the dcr values. If the existing coils are light gauge, their dcr will be signifigantly higher than the Alpha's and this could change things quite a bit. Even if the gauge is fairly heavy, I'll bet the dcr will still be higher than the Alpha 14 ga. and for sure the 12 ga.

P.S You don't need 400v caps for home use speakers, so not to worry about that-200v will be plenty.

gooberdude · « **Reply #2 on:** 16 Aug 2007, 12:47 am »

thanks Mark.

For now i'm not gonna mess with the inductors..way too much there that i don't have a clue about.

I decided to go with a 10 uF Sonicap for the woofer, and a 7.0 uF Dynamicap for the tweeter...also adding a .1uF Sonicap Platinum to bypass the dynamicap.

Soniccraft also sells a 5.5 ohm Mills resistor, and Jeff thought it better than the orig 5.6 Ohm.

I hope i'm not mucking anything up with 7.1 Ohms total capacitance versus the orig 6.8 Ohms on the tweeter... If the Dynamicaps won't work I'll try Sonicaps with the Platinum bypass caps, or maybe something from North Creek audio. Jeff has me curious about bypassing. North Creek promotes Cascade bypassing and sells film & foil caps for that purpose. to do cascading the NC way is still about $50 a pair.

Mundorf Silver/Oil's and 12 ga AQ coils are not in my budget.

From what i've read, for the 10 uF cap its just a fact that a metallized cap is logical, price and space and all. The tweeter position should get a film/foil or paper/oil cap, but its ok to cheat a bit & bypass a metallized with a nice tiny cap or 2. The Platinum bypass costs $60 total, yowzers.

Jeff at Soniccraft did not recomend changing the air core inductor on the tweeter. I don't know anyone who has put a foil inductor on the Si either.

This is gonna be fun.

markC · « **Reply #3 on:** 16 Aug 2007, 07:56 pm »

Just for scientific purposes,

, how about doing an A/B comparison with and without the platinum bypass? Inquiring, (and frugal), minds want to know!

hasselbaink · « **Reply #4 on:** 16 Aug 2007, 08:00 pm »

.
.
Jensen Capacitors is what I would choose. Paper-in-oil, these are head and shoulders above the rest and much cheaper than Mundorf.

http://www.jensencapacitors.com/
.
.

gooberdude · « **Reply #5 on:** 16 Aug 2007, 08:52 pm »

I definitely plan on some experiments. I've kind butchered the stock x-over and so its easy to swap different components in and out. Dave Leonard designed it quite well...

My initial plan is to wrap up the Platinum with the Dynamicap, let them both burn in a few weeks, then yank the Platinum out. Bypassing is voodoo to me, so i figure its best to try it this way, then simply add the .1 uF at a later date, and suffer through that burn-in.

the Jensens are next!! good suggestion.. I'm sold on trying some paper/oil caps on the tweeter when finances allow it.

markC · « **Reply #6 on:** 16 Aug 2007, 09:28 pm »

Sounds like fun. Now the hard part-waiting for the parts to arrive!

gooberdude · « **Reply #7 on:** 16 Aug 2007, 10:29 pm »

funny cuz i just got a call from my doorman...Soniccraft & Fedex came through this time. The hard part is trying to duck out early so I don't miss the mailroom attendant before she leaves at 6:30.

When i installed the new Mills resistors in this x-over, last week, I used the Purist Audio Burn In cd for about 10 hrs afterwards...the Mills sounded like they'd always been there the very next day. They sounded tight, thin & compressed before the burn-in cd... I'm hoping the new caps will take to that CD as well. It does seem to not only break-in gear fast, but does it resolutely...meaning there are NO newness artifacts left over even after just a few hours of play. the harshness is gone and only the opening up of the sound continues for the rest of the process..which is just playin' music.

Supposedly the Sonicap Gen I's are notorious backsliders...they sound good till 70 hrs, then like arse, then warm back up at 200.

markC · « **Reply #8 on:** 17 Aug 2007, 02:04 am »

Wow, that was fast-so get after it and let us know!

gooberdude · « **Reply #9 on:** 17 Aug 2007, 03:47 am »

Good stuff so far. I received the wrong value for the tweeter cap, so i inserted the Platinum bypass on the stock Jantzen. The Sonicap should be killer on the woofer...the sound is so clean & clear. after an hour or so the bass is coming out. very cool.

it'll cook a while, then we'll see. If there's room on the x-over board i'll try out a paper/oil or film/oil cap on the tweeter...along with the Platinum. Open to any suggestions...

kyrill · « **Reply #10 on:** 19 Aug 2007, 10:58 am »

mark c

You warn validly about the dcr values of the default coils
but are these values DC resistance in Ohms? If yes you can easily measure it and take a new coil and if the replacement coil has a different DCR , is it not possible to compensate with (mills) resistors in series w. the coil?

el`Ol · « **Reply #11 on:** 19 Aug 2007, 11:40 am »

Here is a discussion about caps:
http://www.audiocircle.com/index.php?topic=42756.0

markC · « **Reply #12 on:** 19 Aug 2007, 01:52 pm »

Kyrill

Yes, you could add a resister in series with the coil to get the same dcr value, but that's one more component in the signal path.

kyrill · « **Reply #13 on:** 19 Aug 2007, 01:55 pm »

ah ya
but replacing a cheapish coil around a ferrite core with one of the better coils and a mill resistor will still be better sounding overall, i may predict

markC · « **Reply #14 on:** 19 Aug 2007, 02:05 pm »

I would certainly agree with that, Kyrill.

DanTheMan · « **Reply #15 on:** 27 Aug 2007, 02:09 am »

Any updates?

gooberdude · « **Reply #16 on:** 28 Aug 2007, 03:29 am »

All i can report is that i'm a happy Hawthorne customer... the stock x-over seems to be an excellent platform for replacing caps and resistors with little effort.

I have the new 6.8 uF Sonicap for the tweeter, but its not installed. I should have time tomorrow and will report back by end of week. This cap is about 2x the size of the stock Jantzen, hope i don't run out of room on the x-over planks.

Guys, when i'm installing capacitors can they be damaged? By this, i'm mainly talking about bending the wire leads. Are there some common knowledge precautions to heed??? Are caps fragile?

DanTheMan · « **Reply #17 on:** 28 Aug 2007, 05:40 am »

I've bent the leads on the stock crossover quite a bit and have not had any problems. I have been really gentle with them though.

Roy Lewis · « **Reply #18 on:** 2 Sep 2007, 05:34 pm »

This might prove helpful

www.humblehomemadehifi.com/cap.html

Roy

DanTheMan · « **Reply #19 on:** 3 Sep 2007, 09:52 pm »

Quote

This might prove helpful

www.humblehomemadehifi.com

This link doen't work on my computer.