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Caps for crossover upgrade for Opera Grand Callas Loudspeakers

Hi, first of all excuse me for my English.
I’d like to upgrade crossover of my beloved Opera Grand Callas Loudspeakers
http://www.operaloudspeakers.com/en/collections/callas-line/grand-callas.html
I’ve got a Merging Hapi as dac, Soulution 721 preamplifier and Krell Fpb 400cx amplifier, I use pure Ag Lasound cables (http://www.lasound.it/en/)
Here you could find more information about my loudspeakers.
https://drive.google.com/open?id=0B9kNUs8PnpkEa21XMjRmaE5ZdWs
They use Scanspeak 9700 tweeter from 2khz and above, Seas 6" custom midrange from 200hz to 2Khz and two Scanspeak 8" aluminium woofers.
Woofer could be this, but I’m not sure
https://www.scan-speak.dk/products/prod-woofer/?single_prod_id=157
While midrange is very similar to this
http://www.seas.no/index.php?option=com_content&view=article&id=101:h1520-08-u16rcyp&cat...
Here is the schema of the crossover, maybe it could be quite different, I haven’t yet dismount the woofer in order to take photos, but this schema is taken from the my loudspeakers’ little sisters, the Opera Callas Diva, that are a little smaller and with only one woofer instead of two.
http://i66.tinypic.com/etil95.jpg
And here is a photo taken from Opera Callas Diva crossover.
http://i67.tinypic.com/16blocz.jpg
As you can see, and in this respect I know that it’s the same as my loudspeakers, capacitors used are Mundorf Evo Aluminium.
I’d like to change the 6,8 uF capacitor used for the front tweeter and the 10 uF used as bypass capacitors for midrange in order to obtain e more relaxing and refined sound. I’d like to have more air, more natural and organic sound without loss in high frequencies extension.
I like my loudspeakers very much, but sometimes I found the sound, especially with not perfectly recorded and mixed records, a little bit on the hard side in the uppermid frequencies, especially on female voices.
I think it could depends on Mundorf Evo caps that are known to be a little "nervous", so I think to go for a Jupite Copper Foil Paper and Wax caps for the 6,8uF (eventually with a Duelund Silver 0,01uF bypass) and maybe a Jantzen Alumen ZCap for 10uF midrange cap, I know it could be better to use another Jupiter Copper for midrange, but I don’t know if there is enough space for it.
Have you any suggestions?
For midrange caps what do you think of Jupiter VT? What are the differences between Jupiter VT and Copper Foil in terms of sound? And between Jupiter Vt and Jantzen Alumen Zcap?
Thanks.
grunter
grunter OP
9 posts
 
Hi, I update the thread.
After opening loudspeakers and analyzing the tweeter and mid+woofer crossovers I decide to substitute the following components in series with speakers.
Tweeter crossover - Mundorf 6,8uF mcap, anonymous 22uf film cap and ceramic 1ohm resistor respectively substituted with 6,8uF Jupiter VT 100 Aluminium Wax Paper, 22uf Mundorf Supreme Evo Oil and 1ohm Powertron resistor. I have not enough space on the PCB for large 22uf cap, so I decide to go with Mundorf Supreme Evo Oil, good cost/quality ratio and, more important in this case, quite small.
Midrange crossover - Mundorf 100uF electrolytic cap, 2,2ohm ceramic resistors substituted with 2 Mundorf 47uF Supreme Evo Oil caps + 6uF Jupiter VT 100 Aluminium Wax Paper and 2,2ohm Powertron resistor.
Here the space and cost importance are even more evident, cause a 100uF electrolytic cap is very small and cheap than equivalent film capacitors.
The mid crossover has to be made, but I've already done the tweeter crossover changement: much more resolution and information with much less harshness and more natural sound.
Ciao.
Ag insider logo xs@2x
djk33
2 posts
 
Hi Ciao,I also have the Grand Callas.  Were you able to follow through on the mic crossover changes also?  Have you done any other changes to the speaker?Darin
Ag insider logo xs@2x
djk33
2 posts
 
Sorry I meant to type "mid" crossover changes...
fattorino
1 posts
 
Ciao mi chiamo Fabio vorrei informazioni sull'upgrade del crossover delle Opera Grand Callas.O magari condividere pareri.
grunter OP
9 posts
 
Hi, I update the thread, excuse me for being late.

Here are the mods done and to be done.

Substitution - all components are in series with the speakers

Tweeter
1 cap 6,8 uF -> Jupiter VT 100 Aluminium
1 cap 22 uF -> Mundorf Supreme Evo Oil
1 res 1 Ohm -> Powertron FPR2-T218 Metal Foil Resistor 30W

Mid
1 cap 100 uF electrolytic -> 47 uF + 47 uF Mundorf Supreme Evo Oil + 6 uF Jupiter VT 100 Aluminium
1 res 2,2 ohm -> Powertron FPR2-T218 Metal Foil Resistor 30W
(to be done)
add 1 uF bypass cap on 47+47+6=100 uF caps -> Mundorf Supreme Evo Silver Gold Oil

Woofer (to be done)
add 1 47 uF bypass cap on 3x330=990 uF electrolytic caps -> Mundorf Supreme Evo Oil
2 parallel res 1 ohm -> Powertron FPR2-T218 Metal Foil Resistor 30W

As for now I could say the most upgrading mod is sobstituting the 100uF electrolytic cap with the 47+47+6 parallel caps of better quality, the mids now really shines as resolution and thruthfullness.

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