Jolida JD9 Phono Pre Mod...

Toolfan66

So I decided to take my phono pre to the next level, 2 years ago ( maybe longer ) I had upgraded the caps with Clarity MR 1.0's with good results.

This time I purchased some Burr Brown OP637A's and replaced the stock ones..

Let's just say I wish I had done this mod ages ago, the image and clarity is incredible, and the lower end seems to be more pronounced and tight...

Been listening to Dead Can Dance and it sounds better then I have ever heard it..

The sad part is this is such an easy mod, took all of 20 minutes if that, and that was pulling it out and putting it back in..

This is a must do mod for this unit, I have read nothing but good things about it for sometime now glad I finally did it...

Toolfan66

treitz3

I will take it. Daggum, wrong forum.

Tom

Toolfan66

Haha, watcha buying Tom?

treitz3

Your Jolida JD-9. *smiles*

Tom

hochpt21

Me too... Second in line

Cheers

Toolfan66

treitz3 wrote: »

Your Jolida JD-9. *smiles*

Tom

Jhayman

Good work Larry...
30 min of downtime and unlimited hours of enjoyment..

Toolfan66

Jhayman wrote: »

Good work Larry...
30 min of downtime and unlimited hours of enjoyment..

Thanks, it really is easy to do, looking forward to working out this morning, finish up some yard work, and have some time to play with the system for a few hours..

SCompRacer

Nice work! Love it when folks crack the hood and diy!

One other way to go, although more expensive and if you have space for them, are discrete op amps, like from Burson. I did that in a Music Hall 25.3 DAC with excellent results. That would set you back ~ $140 for a pair though. They also offer flexible extension leads.

Toolfan66

SCompRacer wrote: »

Nice work! Love it when folks crack the hood and diy!

One other way to go, although more expensive and if you have space for them, are discrete op amps, like from Burson. I did that in a Music Hall 25.3 DAC with excellent results. That would set you back ~ $140 for a pair though. They also offer flexible extension leads.

I saw those and considered them, do you know how long they are??

Oh, and thanks..

Toolfan66

So I have to say I really can't believe how clean the sound stage is with this mod, I have loved the sound of vinyl, but this really has me revisiting some old titles..

I'm very happy....

hochpt21

I've looked at this unit for a few years now (from afar ) I've only heard good things about the stock units...the modded ones must be a dream.

Toolfan66

hochpt21 wrote: »

I've looked at this unit for a few years now (from afar ) I've only heard good things about the stock units...the modded ones must be a dream.

It is a dream, Led Zeppelin II sounds incredible right now..

SCompRacer

Toolfan66 wrote: »

I saw those and considered them, do you know how long they are??

I had the first design which IIRC were larger. This is a current spec page from Burson. Fairly sure the OEM op amp in the JD9's were dual (OPA2604 or OP37), so the 21mm (.82") thick one is the dual. 16mm (.62") wide and 42mm (1.65") tall.



Aaron has the Music Hall 25.3 DAC now. Someone had it and reversed one HD op amp of a matched pair upon install and smoked it. (It was best to remove the Burson HD op amps from socket when shipping). I got the DAC back and tested it with OEM op amps and it still worked. Aaron bought it and purchased the newer design Burson's to replace the matched pair. It had three op amps total. IIRC one dual was for tube output, two were for balanced out SS output.

I got mine from Parts Connexion. I think Aaron may have bought them direct from Burson. They also offer this 35mm extension for remote mounting.



These were the first design in the 25.3. They near touched the top of case.

Toolfan66

SCompRacer wrote: »

Toolfan66 wrote: »

I saw those and considered them, do you know how long they are??

I had the first design which IIRC were larger. This is a current spec page from Burson. Fairly sure the OEM op amp in the JD9's were dual (OPA2604 or OP37), so the 21mm (.82") thick one is the dual. 16mm (.62") wide and 42mm (1.65") tall.



Aaron has the Music Hall 25.3 DAC now. Someone had it and reversed one HD op amp of a matched pair upon install and smoked it. (It was best to remove the Burson HD op amps from socket when shipping). I got the DAC back and tested it with OEM op amps and it still worked. Aaron bought it and purchased the newer design Burson's to replace the matched pair. It had three op amps total. IIRC one dual was for tube output, two were for balanced out SS output.

I got mine from Parts Connexion. I think Aaron may have bought them direct from Burson. They also offer this 35mm extension for remote mounting.



These were the first design in the 25.3. They near touched the top of case.

Thanks for the info, I would definitely need the extensions, and even then I might have to still do some modding on the case, or just build a new case..

[Deleted User]

Hello,
There is a person on the DIY Audio forum who removed C16 on both channels and replaced with a wire that noticed a significant improvement. This is a 220uF cap that is connected to R8 and seems to be superfluous since the IC is configured with dual supply voltages eliminating any DC offset.
Regards, Ken

Toolfan66

Thanks Ken,

I will look into that as well..

Toolfan66

Can't wait to go home fire up the stereo!!! I feel a little VH or RUSH hitting the table..

Dawgfish

Nice work! I've done very similar mods to my JD-9. I used Obbligato Gold caps and instead of all op-amps being OPA637s, I used LT1028s for the right must pair and OPA637s for the center and left pair. I've tried all OPA637s, but think its a little quieter with the LT1028s on the right must position. I also tried AD843s on the left most positions per recommendations on other boards, but found the AD843s to add to much hiss. I've tried many different tubes in the JD -9, but have ultimately settled on Telefunken smooth plates as my favorite. They give great detail and soundstage with a touch of warmth. I like them way better than the rib plates. Great work! Modded JD-9s sound spectacular. I have no intentions of upgrading mine.

Dawgfish

Upgrading to another phono pre that is.

Toolfan66

Dawgfish wrote: »

Upgrading to another phono pre that is.

Me either,, the op-amps were such a huge improvement, I will be happy with this for a long time...

You feel like you just upgraded to a phono pre that would be in the $1k or better range..

Dawgfish

Exactly, I feel the same way. I think it gets all of the bases done right: detail, dynamics, soundstage, prat, and relatively good quietness. It does it all.

hochpt21

I'm considering an unmodded Jolida JD9. I have never modded electronics before.

Few questions.

From a bit of research it seems these Burr Brown op amps may make the biggest impact. To switch these out, are they just 'plug in'? Or is there soldering involved?

http://www.ebay.com/itm/Burr-Brown-OPA637-Precision-Hi-Speed-Difet-OPAmp-OPA637-/160299583574

Are these the OP amps^^^

Is $39 each about right? So around $235 for the mod?

Finally, would this be the same mod on the Jolida JD9 mkII ??

Thanks for the help, just trying to figure out what my total cost would be if I got one of these.

Thanks,
Paul

HallmanLabs

Not to raise a thread from the dead, but does anyone have a direct link you can provide for purchasing the flexible op amp extensions pictured and mentioned here?

I am a reviewer for Burson Audio and Orange Amplifications, neither of them directly sell these flexible extensions (I've asked). I also checked the site mentioned (Parts Connexion) and could not find them anywhere.

Thanks for any help! I've been trying to run down a retailer selling these for months.

If anyone is curious, here is my site: www.ZoSoNCSU.com As of now I only have one in depth review posted, but I am working on a big review and build log for an ESS ES9038Pro build (DSD64 to DSD1024 native decoding).

agfrost

Is this the part, on the Burson site (offered as add-on to opamp purchase)?
https://www.bursonaudio.com/products/supreme-sound-opamp-v5/

Toolfan66

http://www.audio-gd.com/Pro/diy/OPA/OPAEN.htm

HallmanLabs

Thanks guys, I really appreciate it.

I'm kind of confused why Burson in fact DOES offer them, but Burson Audio themselves told me they don't sell them, lol.

Isn't $20 a pair + $15 S/H at Burson a little outrageous for 35mm? What are they using for the extension wires? Solid Silver?

Over at AudioGD, which of the extension designs do you think would best suit me if I am mainly testings op amps like the Burson V5-OPA? Although it is technically "discrete", it doesn't have near the power requirements compared to Audio GD's discrete offerings.

Edit: just noticed the change in price from the normal Audio GD extension and the one with a power capacitors is only 10 cents, lol. I might get pairs of both styles for less than $4 each.