Jolida JD9 phono amp hybrid Magic...

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face

Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #60 on: 25 Jun 2010, 07:37 pm »
The resistors are AN Tantalum from Parts Connextion.  I've used them in other applications and have been pleased.  I'm also only changing out only the resistors I use for loading, not all of them.  Sorry, no extra 100R's at the moment.

undertow

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Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #61 on: 25 Jun 2010, 07:55 pm »
I just ordered a pair of the Vishay Var-Series "Naked" 100R. Chris at parts connexion says these are now the best resistors in the world which he carries for any phono loading. They are just to the market I guess and they just started taking orders like 2 months ago on them.

They are crazy looking suckers and very pricey at 3 times the cost of the other premium types, but I figured if I need to pay 20 bucks to fed ex from canada why not? Also I spoke with him about the space in the JD9a for the input board on these, I doubt they would fit easily at all, so Instead I will simply just turn off the Load dip's all together, accept for the Gain switches of course, and just solder these right onto the WBT's jacks giving plenty of space and a direct connect to the load just simply putting one of these on each jack from center pin to ground pin on each channel... Should be exciting! Check out the link to these resistors.
http://www.partsconnexion.com/resistors_vishay_var.html

« Last Edit: 25 Jun 2010, 11:28 pm by undertow »

etcarroll

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Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #62 on: 26 Jun 2010, 11:59 pm »
You needed to use the macro feature of your camera for last 2 pics.

Interesting post/changes nonetheless.

face

Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #63 on: 28 Jun 2010, 04:03 am »
That's for the info and images Undertow.

royphil345

Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #64 on: 4 Jul 2010, 12:58 am »
That's starting to be a SERIOUSLY tweaked out Jolida! Wish I could hear it!

For the less inspired, my experiment using silver mica capacitance loading plugs instead of the cheap internal ceramic caps has worked out very, very well. The cloudy, harsh in the upper midrange and light on the bass "Jolida sound" has almost completely cleared up. I think it sounds way more open, extended and detailed now and this is a very cheap and easy tweak. I have no idea why they put ceramic disc caps as the first thing in the signal path. All the other parts seem much better suited to where they are in the circuit.

Here's a rip done with an AT440MLa. This cart was always extremely lean sounding and pretty much unlistenable with the Jolida. There's actual bass now!... and it sounds detailed... not just bright in the upper mids. Still not the richest sounding cartridge with the Jolida, but a huge improvement I think. Just smoother, more balanced and more "open" sounding. This is with the Python Y-adapters from eBay and 89pF capacitance plugs (a 50pF and a 39pF in parallel). This value seems to sound best with my Ortofon 2M Blue as well.


http://www.4shared.com/file/tiUfwuHa/jolida_89pf.html


EDIT:  It would probably help to post the same rip using the Jolida's 100pf setting instead of my capacitance plugs. Less bass weight, detail, frequency extension... Not as smooth... The whole tonal balance does seem to get a little top-heavy which is probably the reason for the "brightness" people talk about, along with the lack of deep bass and smoothness in the highs. This little mod really makes QUITE a difference... and you don't even have to take the cover off. Here's the rip using the Jolida's cheapo internal ceramic discs for capacitance loading... I think it would be tempting to set the tonearm settings a little differently to try and get rid of the "congested" sound from the cheapo ceramic caps. Probably another cause for the "bright" sound people complain about.

http://www.4shared.com/file/85CDYmNh/jolida_using_internal_100pf_ca.html
« Last Edit: 20 Jul 2010, 11:19 pm by royphil345 »

undertow

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Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #65 on: 15 Jul 2010, 04:14 pm »
royphil345,
For sure the loading devices do make a difference, they choke off some of the transparency of this unit. The loading resistors and caps are easily done by just connecting right to the back of the RCA inputs.

However, if you modify that micro board it is a serious task! But I did, only for the future if I need to test a different loading, but I only replaced the single resistor I needed, which in this case was suggested by Partsconnexion as the best of the best, the Vishay naked "Z"… Pricey at 15 bucks a pop, however, they are SMALL enough unlike the barrel type resistors from Audio Note etc…. to fit anywhere you want, its no bigger than the 3 cent Radio shack style resistors on it now due to this resistor is flat and tall, opposed to large and round like other replacements. Luckily it’s the best you can get as well.

Anyway I replaced this first… It did have a significant change in tone and I would say added a slight transparency the old resistor did not being a little hazy… Now the Bass maybe became more defined with this for sure.
 
HOWEVER, because I have been crazy enough to use a pair of Duelunds in this unit just for experimental purposes and ended up with great results, I decided to also order on top of the "Loading" resistor a pair to replace the "GAIN" resistor's as well.
 
In the Jolida of course you have 3 choices:
70-db gain = resistor value of 1k or 1000 ohms
85-db gain = resistor value of 100 ohms
95-db gain = resistor value of 33 ohms

Well I needed a little more bite than the 70 db provided for my MC cart. with .4 mV output, and less than the 85 db as it got really strong. So I went with a 470 ohm Naked "Z" to replace right in the middle getting me somewhere between 75 and 78 db… This worked excellent, but the unexpected side effect, this was the most significant sound upgrade to this unit yet!

First the Gain not just the loading resistors in the unit REALLY were choking off the dynamics of the cartridge for sure, because holy cow the background is so silent now, and the bass is so incredible with much smoother top end, and this of course even after the Duelunds and better op amps went in.

This makes sense because this is really the first gain component your Cart. sees coming into the jolida, and it really makes a HUGE difference having a quality resistor right there in line opening up this signal to the gain board and opamps. These resistors are not on the Gain board itself, but on the "Loading" board with the loading caps and resistors that have the dip switches on the back of the unit.

The gain resistor is the one you want to change for sure maybe even over the loading. Also this is a good opportunity to fix the big complaint on this unit putting in your own custom gain setting like I did so its not too high or too low of power. This is funny because Jolida tried addressing this with that other Goofy potentiometer board of course on the outputs so you could use the lower or higher outputs. But one single resistor of high quality right at the input to do it right blows the doors off this unit, I am not kidding.

However, if you wish to do this mod it’s the most difficult because you can melt the dip switch as the connections are so close your iron can physically touch the plastic trying to remove and replace, you would not damage the board or traces too easily overheating it, but just the position of the plastic on the switches makes it a pretty tough one, plus you do have to unscrew the board, both boards the gain stage and the loading board and possibly remove all the wires to make it easier on top of that. Otherwise you could remove the loadingboard from the circuit all together and point to point hardwire, of course this is easy for the loading resistors or caps right at the RCA, but the gain resistor is in series going in and back out of the switches you would be eliminating taking out the loading board, but you would get plenty of space and fairly easy mod if you can trace it and wire it up right. I decided the extra 2 hours doing it right was worth keeping the integrity and original operation of the unit for other cartridge choices in the future.

This might be the single most effective mod to see where your sound stands on this unit, truth is everybody always goes backwards starting with the ouput caps and tubes!

I guess they are the easiest as most of those parts and values are easily seen, and of course in the audio world they are in the top tier of critical components.

But if the signal is generic from the cart. because of this cheesy load and gain resistor combo your already severely limiting your signal integrity, I can hear this clearly after the mod. Remember this is not a powerful electric signal coming off that Cart. its virtually at the mercy of very small signal change, not like an amplifier, preamp, or digital device, it’s a phono amp, and a cartridge is hyper sensitive to its resistance and output levels, so if anything makes sense than the resistors directly loading, and setting the gain or caps connected directly to the dead signal off a passive cartridge are probably the most critical to get right off the bat.          
« Last Edit: 17 Jul 2010, 04:36 pm by undertow »

royphil345

Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #66 on: 16 Jul 2010, 04:49 pm »
Yes, I haven't done near as much experimenting as you have... But, I have been coming to the same conclusion that the beginning of the signal chain is extremely important in getting the best sound out of vinyl. It seems accuracy is very important nearest to the source. I've also noticed that different phono stages definitely seem to sound more dramatically different from each other than preamps, amps or other components.

I'm definitely not messing with that little loading board. I thought about putting my silver mica caps in it, but I saw traces and holes for the leads like right on the edge of the board. Looked like a bigger risk than I was willing to take. I'm happy with my capacitance loading plugs. I didn't think there was that much difference among different resistors besides tolerance accuracy, but I guess I'll have look into that now too. Always learning... Thank you very much for all your input. You inspired me to at least try something and my Jolida is sounding a heck of a lot better already. I may go a little further with improving more parts over time. I'm pretty satisfied with it now though. That little tweak really exceeded my expectations and fixed what was bugging me about the Jolida. I imagine sooner or later something else will start bugging me and I'll want to try further improvements... lol. Seems to be the pattern in this hobby...

Doronor

Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #67 on: 2 Sep 2010, 06:49 am »
Interesting observations, Undertow:
My friends and I would like to thank you for all this info. You inspired us to upgrade this unit's caps and with great results. After the changes, compared with the stock, this unit is unrecognizable...
Note 1:
The Op-amps recommendations did not work for us - for what ever reason the top of the line AD843KN increased the noise floor in our units (it started hissing on stand-by) without really improving the dynamics. The Burr Brown OPA637BP did not work for me at all - it produced a very high pitched squeel (like a TV would do sometimes) and I yanked it out before there will be damage. Could be a faulty batch of OPA637BP.

Note 2:
Among many others, including ClarityCap MR, AmpOhm, Mundorf Silver in Oil, we tried V-Caps TFTF caps but did not like them at all, in 4 different high resolution systems (two based on ESL panel speakers driven by powerful tube amps, two box speakers' based, driven by SET and OTL): The V-Caps, to our ears, were extremely dynamic (probably the best we heard in that regard) but sounded sterile (chopped off decay, lack of mid range texture, sort of glossed over, overly smooth/slippery and synthetic sounding to our ears). Your mileage may vary and different people have different tastes.
I would like to say that the ClarityCap MR is pretty dynamic too and more than anything it has excellent PRAT but compared to some paper in oil and Mylar in oil caps, it sounded a bit mechanical and solid state like to our ears. It also starts to congest and pinch the sound a bit, when faced with loud and complex audio passages. On the up side it has an excellent mid bass punch. 
I believe that to an extent, this is inline with your observation of the ClarityCap MR Vs Duelund cap.
There is more refinement, effortlessness and relaxed sound presentation with the PIO and with some Polyester in oil caps in our mind.
If I had to compare them to amplifier topologies I would say the ClarityCap MR sounds more like push-pull while some paper in oil caps sound more like a SET or an OTL.

Note 3:
As opposed to some views out there, re potential degradation of the sound by by-passing (potential timing/phase distortion), from our experience, most caps benefitted from by-passing with 0.01 uF Vishay MKP1837 and/or 0.01 uF Polystyrene cap  - they gave more top end extension and smoothness which translated to more air around the instruments and better ambiance retrieval.

At the end of the day, whatever cap you like, this Jolida JD-9 can be vastly altered for the better by replacing its caps which makes it a great playing ground for audiophiles...

Thanks again, Undertow for your invaluable info!


PatOMalley

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Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #68 on: 21 Sep 2010, 02:38 am »
The AD843KN are not at all usable as a replacement for all 6 OPA's in the Jolida. You'll get a lot of nasty noise instead of "nasty subsonic level bass". I have tried them, too. You may use two of them for the output stage only, where they work quite well. They sound a bit less harsh than the original OP37.  ...

Which are the output opamps? Say, looking from the back of the chassis down at the board? I was thinking they are the set on the right - the ones close to the center of the board. - is that them?

PatOMalley

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Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #69 on: 29 Sep 2010, 02:34 am »

[snip]
..., go in the unit and change just the first input pair of opamps which in my unit are when you have the unit open and your looking at it from the front the 2 chips all the way to the right inside the unit, [snip]

So from the front the input opamps are to the right and the output opamps are to the left.

mine has the opa37. so the soft burr Brown will stay in in the first two set of slots with the AD834 at output .. and maybe I can have the best of both.

I already change output caps to 1uF Obbligatos by passed with the Vishays. nice smooth with a nice top end that is not overly tinkly.

Also using RCA blackplate 5751s.

Funny thing about the thing is that it does not like my cinrmags /w DL103. A little muddy. So i switched to 100ohm active loading and I like it just fine. A bit more lively but the 103 is pure narcotic. And the DL102 is very nice thru the preamp as well. More detail than you would at first think. And a lot less noise.

PatOMalley

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Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #70 on: 13 Oct 2010, 01:49 am »
I might be just talking to myself here but here it goes anyway:
So far I have Obbligato's bypassed with .01uF Vishays.
I removed the tube shields and had RCA 5751 black plates.
all nice but it did not rival my Hagerman Cornet2 in imperial breadth and extension. But I don't think that is what this pre is all about anyway because ...

I have been thinking about replacing the wideband RCA 5751 blackplates with current production Tung Sol 12AX7 just to get a AX7 back in play because maybe that is really what the pre wants. Things were just a bit grey as is.

Then my AD843KN opamps showed up in the mail today so I replaced the output set of OPA37 and put in the Tuing Sols.

BIG improvement. Level of presence is whaay Up. I get the feeling "i am done with mods on this baby." detail improved, presence, dynamics, and a bit more openness. Still not as extended as the hagerman but that may it's signature. In any even I now love this Jolida.

thanks you, boys. You been a big help.

royphil345

Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #71 on: 14 Oct 2010, 05:54 am »
I found the Jolida to be very responsive to tube rolling and I liked the Tung Sols very much in there too. They were my second choice to the Sovtek LPS out of many tubes I tried. Although, that may have changed with the fine-tuning I've done since. I'll never know, because I thought I was decided and gave the Tung Sols away awhile back. Now, I do sort of wished I saved them to try again after a period of tweaking things and finding the perfect settings on the Jolida over time.

sherod

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Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #72 on: 27 Oct 2010, 02:36 am »
Doroner,
  I'm curious what output caps you and your listening panel ended up preferring? Also, Undertow, do you still have the Duelunds in your outputs? I'm wondering if after getting used to them, you might put the Claritycap MR back in for a final evaluation with your favorite music. maybe try a larger value pair equal to the Duelunds.   :D

Doronor

Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #73 on: 30 Nov 2010, 06:14 am »
Hi Sherod,

Sorry for the delay. My notification did not work somehow.
The best overall cap in our mind is the AMP OHM Polyester in Oil Aluminum Foil.
It is the least damaging to the sound, it is the most neutral sounding, the airiest, most detailed (great ambiance retrieval) without being etched or bright and by far the most extended top to bottom cap we tried.
On the negative side if your speakers are on the lean side it will not add beef to the sound like some PIO do. So "the best" not only depends on personal taste (and everybody listens differently and has different preferences) but also what basic system are you starting with and what improvements are you looking for.

Close seconds in our tests are the AMP OHM PIO Copper foil - very rich, seductive mid range, very good presence and tonality to die for, especially with horns and percussion - to my subjective ears it gets the most realistic sounding percussion I have ever heard.
On the negative side - it is not as airy nor as extended as the Polyester in Oil. So life is a compromise - pick your poison.
I would say Diana Krall will sound better with the PIO (more lush, sweeter, less raspy as if she had a cold or something :-)). Big Orchestral Piece will most likely benefit from the Polyester (especially tympani's or any large drum) due to its ambiance retrieval and good extension.
Ironically, the company went bankrupt and hence these caps are no longer in production. There are some talks about getting back to production (Audio Cap in the UK) but nothing came to fruition.

My friends recently tried Obbligato Gold Premium Caps and really loved them. They claim they are pretty close to the AMP OHM Polyester In Oil Aluminum Foil. I never tried so cannot voice an opinion.
For their low price they are surely a low risk buy.

Some other caps we tried and were not impressed with:
V-Caps - over hyped and very pricy. On the positive: it is definitely the most dynamic cap I have heard (feels like your speaker drivers got a turbo motor). Very detailed too. On the negative: it has this annoying gloss-over quality, lack of textures (too slippery smooth) a bit of a chopped off decay. It has no soul in my mind (here is a link for someone who thought along the same lines:http://www.6moons.com/audioreviews/caprolling/caps.html).

I find the Clarity Cap MR to be congested and mechanical sounding compared to the above mentioned AMP OHM Caps. On the positive: it has very good PRAT and mid bass punch (a rocker).

I find the Mundorf Silver In Oil to have smooth airy highs (great for a tweeter cap in a speaker) but sloppy and slow bass (as if reproduced by an under-powereed-for-the-application-SET amp).
The Audio Note Polyester in oil Copper foil, while not a bad cap, does not match these above mentioned to our taste.
It has some nice mid range warmth and is full bodied but is congested (lumps instruments together rather than separates them, when the recordings allows for it).
ModWright caps did not do it for me either - clean sounding but slightly dry and flat sounding (solid state like) - nothing to write home about to my taste, in my system.

I never tried the Duelund nor the silver Audio Note as they are price prohibitive in my mind and after getting "bitten" by the V-Caps I am scared to spend hundreds of dollars just to realize I may not like them.

Bear in mind that this is purely subjective - it may be unavoidable to try different caps for your self to find your soul mate and another advise is to take any cap review (tons of them lately) with a big grain of salt, mine included of course.

Tube wise - after getting so much junk on e-bay (half dead tubes from people claiming NOS) I would say one of the best bets are the Shuguang Psvane 12AX7 from Grant Fidelity: although not as neutral and clean, they are not far behind the Telefunken Smooth Plate clarity wise, very lush, seductive mid range without being syrupy, good bottom end and very sweet: http://grantfidelity.com/site/Pavane_Psvane_Reference_12ax7T_Shuguang_tube

Enjoy the music!










dwr

Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #74 on: 6 Dec 2010, 03:47 pm »
Doronor, do you have anymore feedback or info on the Obbligato gold premium caps. I have a JD-9 unit that I am just going to start making some of these mods on and was wondering. I ordered a pair, figuring for the price its really a no brainer to try them. I am having trouble finding a pair of the ampohm polyester in oil caps since the company is out of business, would the paper in oil aluminum foil caps be a decent alternative?

Dan

Doronor

Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #75 on: 7 Dec 2010, 01:38 am »
Hi DWR,

From my friend's impression the Obbligato Gold comes damn close to the AMP OHM Polyester In Oil and in fact they think it betters the PIO Copper Foil, in this application.
I have compared the Copper Foil in this application and downstream in my JAS Array 300B/805 SET amp, where it did a better job than in the phono stage (could be that some caps work better in a specific range of voltages than others).
The PIO aluminum foil might be the next closest thing although paper always sounds a bit duller/softer to my ears.
Perhaps try both and post your impression.

I think I am going to try the gain resistor upgrade next to see if it brings some more magic.

I am very thankful for this thread information exchange - I think after music loving this is what this hobby is all about.



dwr

Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #76 on: 7 Dec 2010, 02:52 am »
Doronor, I completely agree with your last sentence in that post, I will start with the caps as far as upgrading this unit, and I am sure I will do further upgrades following the info from the postings and info here. Thanks for the info on the caps, and as you said in an earlier post I am just going to have to find out what sounds best to me in my rig.

Dan

roger15ohm

Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #77 on: 7 Dec 2010, 04:36 am »
Hai all,

I am going to NZ latest mid of next year.  Will station there for years to come.  May i know where to buy this phono in NZ?


Best regards,

Wan

dwr

Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #78 on: 27 Dec 2010, 08:27 pm »
OK fellas, I started the mods today on my JD-9. I started with the caps, and used Obbligato gold premium 1uF 630v caps for my replacements. Wow, there is just no way only changing caps should have that much improvement in the overall sound of the unit. I am pleased way beyond my expectations, I am using Siemens ECC 83 tubes which I like in phono stages and the sound is fantastic. I have a MFSL copy of Supertramp Crime of the Century on right now. So what would any or all of you suggest for the next step (op amps??), maybe someone can put the mods in some kind of order most improvement to least? Thanks guys.

Dan   

Doronor

Re: Jolida JD-9A phono amp hybrid Magic...
« Reply #79 on: 30 Dec 2010, 06:05 am »
Hi Dan,

Glad you found out how good the Obbligato caps are.
These are the proof that one need not spend huge amount of money to get good sound.
I tried them in the input section as well (there are a bunch of 4.7 mfd caps near the op-amps) and they smoothed out the sound.
Also, just recently tried the Vishay Z-foil resistors to replace the 33 ohm ones (my Dynavector 17D3 has 0.3 mV output).

I used 47ohm but given the low cartridge output, I may try to bypass the
resistors altogether just to try (best resistors are no resistors).
The Z-foil is special: more information coming through without thinning of the sound. These are ultra detailed resistors.
More extension top to bottom as well.
All I can suggest is do one upgrade at a time to be able to track what each does.
this unit now is an Audia Flight killer
Happy tweaking!