I'm think about ditching the 4 - 10uf Axon output coupling caps and swapping them for 3.9uf mundorf silver/oil temporarily. Into a 20K line stage input impedance this should give me a Fq -3 of about 2Hz.
Later on I'd plan to parallel these with 4 other 3.9uF bringing the the values to just under 8uF (when I can afford them!). The only reason I'm picking this value is space - I can't go larger.
Anyone see any problems with this? Anyone recommend any other film/foil/ poly? My other choices might be the Sonic Cap - Gen Is or the new Modwright metalized oil-impregnated polypropylenes. Recommendations anyone?
thanks for your help!
Barry
Later on I'd plan to parallel these with 4 other 3.9uF bringing the the values to just under 8uF (when I can afford them!). The only reason I'm picking this value is space - I can't go larger.
Anyone see any problems with this? Anyone recommend any other film/foil/ poly? My other choices might be the Sonic Cap - Gen Is or the new Modwright metalized oil-impregnated polypropylenes. Recommendations anyone?
thanks for your help!
Barry
I'm going with Wima MK4S 10 uF to start, and I'm going to
put space in my layout to bypass with Mundorf 1.0 uF silver/gold.
I'll fork over for the Mundorfs in a couple months or so.
First I have to get the amps going and that's a ways off
yet.
I have no experience with this - I'm just doing what seems to
make sense from a cost and space perspective.
Cheers.
put space in my layout to bypass with Mundorf 1.0 uF silver/gold.
I'll fork over for the Mundorfs in a couple months or so.
First I have to get the amps going and that's a ways off
yet.
I have no experience with this - I'm just doing what seems to
make sense from a cost and space perspective.
Cheers.
Well, I always try to stay away from exotic parts discussions, however this time I would like to point out that there are 'weaker' links in the chain than the output coupling cap.
For example, the mc-front end passes its signal via a 220uF elco; and as you've already found out for sure, the XOno uses again a 220uF elco to pass the signal from Q15 to the MM-stage, where in the predecessing Ono a 10uF film cap was used.
Just to give you the idea.
If this is relevant or not, you decide for yourself. All the best, Hannes
For example, the mc-front end passes its signal via a 220uF elco; and as you've already found out for sure, the XOno uses again a 220uF elco to pass the signal from Q15 to the MM-stage, where in the predecessing Ono a 10uF film cap was used.
Just to give you the idea.
If this is relevant or not, you decide for yourself. All the best, Hannes
Hannes Thank you!
So from what your saying there are 2 x 220uF electrolytics in the Xono signal path even before you reach the output coupling caps?
I think that does matter even more than the output! I'll consider replacing them with higher quality parts (BG Ns) and will try to find a schematic on the board here although the caps should be easy to find. As you may have guessed this is a commercial unit and I just purchased it used.
Any other suggestions or links would be helpful.
Kindest regards,
Barry
So from what your saying there are 2 x 220uF electrolytics in the Xono signal path even before you reach the output coupling caps?
I think that does matter even more than the output! I'll consider replacing them with higher quality parts (BG Ns) and will try to find a schematic on the board here although the caps should be easy to find. As you may have guessed this is a commercial unit and I just purchased it used.
Any other suggestions or links would be helpful.
Kindest regards,
Barry
This is kind of the reference of Caps and their associated sound qualities. It appears that Tony Gee has spent more time listening to and notating the changes different caps make than anyone I know of.
http://www.humblehomemadehifi.com/Cap.html
Enjoy.
DaveM
http://www.humblehomemadehifi.com/Cap.html
Enjoy.
DaveM
Hannes is right. There are other weaknesses than the output capacitors.
I experimented with a number of choices and even bypassing the output capacitors as Netlist suggests. The bypassing leads to a "different" sound to my ears. I would not say categorically better.
I did replace two capacitors that Hannes referred to, as well as a number of other electrolytic (in fact, all except for the rail capacitance) with Black Gate NX. Again, listen for your self. One thing I'd recommend is not to skimp on the amount of capacitance, as I learned this early on. The one capacitor that was increased to 1000uF on the Xono was for a reason. It sounds better
I ended up using 2x470uF here.
As for bypass capacitors on the coupling capacitors, I found the best (better than the Mundorf silver I tried) were the Vishay/Roederstein MKP1837.
Again, your opinion will vary. For example, everyone that listens to my equipment thinks it sounds bright and over-analytical. Perhaps it does. Things like Miles' trumpet, the 7th note that the solo violin plays on Lalo's Symphony Espagnole, or the upper register on Gould's decrepit old pre WW piano *should* sound harsh and bright in my opinion
I experimented with a number of choices and even bypassing the output capacitors as Netlist suggests. The bypassing leads to a "different" sound to my ears. I would not say categorically better.
I did replace two capacitors that Hannes referred to, as well as a number of other electrolytic (in fact, all except for the rail capacitance) with Black Gate NX. Again, listen for your self. One thing I'd recommend is not to skimp on the amount of capacitance, as I learned this early on. The one capacitor that was increased to 1000uF on the Xono was for a reason. It sounds better
I ended up using 2x470uF here.As for bypass capacitors on the coupling capacitors, I found the best (better than the Mundorf silver I tried) were the Vishay/Roederstein MKP1837.
Again, your opinion will vary. For example, everyone that listens to my equipment thinks it sounds bright and over-analytical. Perhaps it does. Things like Miles' trumpet, the 7th note that the solo violin plays on Lalo's Symphony Espagnole, or the upper register on Gould's decrepit old pre WW piano *should* sound harsh and bright in my opinion
This thread makes my fingers itch. I've looked at it several times...and almost posted several times...but some of the things I would suggest would amount to redesigning the circuit. For the nonce I will leave well enough alone.
At present, I will limit myself to this: If you want a decent selection of better quality caps, take a look at www.percyaudio.com.
When I do the coupling cap thing, I generally go one of two routes--either a WIMA polypropylene bypassed with a small polystyrene, or the MIT polystyrene & foil (RTX? can't remember the nomenclature at the moment). Mouser has some of the WIMA caps, but not all. They also carry Xicon polystyrene.
Grey
At present, I will limit myself to this: If you want a decent selection of better quality caps, take a look at www.percyaudio.com.
When I do the coupling cap thing, I generally go one of two routes--either a WIMA polypropylene bypassed with a small polystyrene, or the MIT polystyrene & foil (RTX? can't remember the nomenclature at the moment). Mouser has some of the WIMA caps, but not all. They also carry Xicon polystyrene.
Grey
BG N caps are usually better for coupling than most other film caps, and I compared them to MIT RTX, Hovlands, Jensens, Russian PIO, Wondercaps, Wimas and whatever else you can think about. The only ones that sounded better to me were teflon V-Caps.
And with Ono, you can trim the output offset, which is very stable after that ( less than 1mV drift) so you don't need any caps at all.
My Ono below, V-Caps used for PS bypass only, offset adjusted with a trimpot.
And with Ono, you can trim the output offset, which is very stable after that ( less than 1mV drift) so you don't need any caps at all.
My Ono below, V-Caps used for PS bypass only, offset adjusted with a trimpot.
Attachments
Thanks all! Stayed up till 2:30am last night and tracked down all the threads & schematics. Oh, how to stop yawning at work?!
First this is a commercial Xono I just bought used and am modifying. A little squeamish about this (foregive me Wayne!).
#1 Replacing the output caps C7 & C9 using a trimmer around R4 10K & R59 1K seems perfect aiming for 1mV DC.
#2 Replacing the 2 MC/MM signal path coupling caps C37/ C10 with maybe the NX35 V 680uF??????
The PS uses diode bridges which I'll replace with Schottkys which should also clear up any fuzz. Haven't checked, what's the 3rd bridge for -- the muting relay?
Any value in playing around with better RIAA caps?
Barry
First this is a commercial Xono I just bought used and am modifying. A little squeamish about this (foregive me Wayne!).
#1 Replacing the output caps C7 & C9 using a trimmer around R4 10K & R59 1K seems perfect aiming for 1mV DC.
#2 Replacing the 2 MC/MM signal path coupling caps C37/ C10 with maybe the NX35 V 680uF??????
The PS uses diode bridges which I'll replace with Schottkys which should also clear up any fuzz. Haven't checked, what's the 3rd bridge for -- the muting relay?
Any value in playing around with better RIAA caps?
Barry
I'm a little confused about the caps. I don't have an Xono
schematic. But I do have an Ono schematic. So - does anyone
know what parts were changed ? Was it both C37 and C19?
If only one, which one? Any improvements I can make would
be welcomed and this sounds like an important one.
I'd love to get rid of the output caps
also. So I'll also try your idea Barry with the trimmers.
schematic. But I do have an Ono schematic. So - does anyone
know what parts were changed ? Was it both C37 and C19?
If only one, which one? Any improvements I can make would
be welcomed and this sounds like an important one.
I'd love to get rid of the output caps
also. So I'll also try your idea Barry with the trimmers.
Check the schematics, C19 is also an electrolytic and is in the feedback path, so theoretically it should correct capacitor nonlinearities, especially of C37. I would replace it with the same type and value! And use the same bypass if you are using bypass. And while you're at it I would then use the same type in them MM stage for C1 / C41 (or use one bigger cap for them).
Some people prefer the sound of Nichicon KZ capacitors (their top of the range) and find the Blackgate to sound coloured or rolled off. This is all VERY subjective. Lastly, Blackgates are said to need a long break-in time so don't be surprised if it sounds worse, at least in the beginning.
Edit: Forgot to mention, if I would modify a stock XONO at all, I would probably look into the RIAA caps first. Board space permitting (!), I would use some (extended foil) styroflex or teflon film and foil caps, say from Rel Caps and, very important, match them channel to channel as close as I can.
My 2 cents.
One last ? or 2
I must have a bad schematic (despite several board searches and downloads). My layout has no C19! Could someone send me one please or post it ?????
Also for those interested the Xono inverter's R59 is 475 ohms not 1k and R13 is not 332 but 3320 ohms. (an error on my Ono schematic?). Q6 is a 2SA991, not 2SA953.
Thanks again for all the help!
Barry
I must have a bad schematic (despite several board searches and downloads). My layout has no C19! Could someone send me one please or post it ?????
Also for those interested the Xono inverter's R59 is 475 ohms not 1k and R13 is not 332 but 3320 ohms. (an error on my Ono schematic?). Q6 is a 2SA991, not 2SA953.
Thanks again for all the help!
Barry
I don't have an electronic copy of the schematic - so I can't
send it to you. Mine is not Xono anyhow... but here's what I
have:
C19 is 220 uF in parallel with C83, 0.01 uF as bypass.
These two caps are in series with R51, 475 ohms.
The 3 components above are feedback between the drain
and gate of Q15, a 2SK170 which provides gain in the MM
section output.
send it to you. Mine is not Xono anyhow... but here's what I
have:
C19 is 220 uF in parallel with C83, 0.01 uF as bypass.
These two caps are in series with R51, 475 ohms.
The 3 components above are feedback between the drain
and gate of Q15, a 2SK170 which provides gain in the MM
section output.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.