[Russtafarian]

Last week I took delivery of the Oppo 980 and let me say up-front that this player is a gift to simpleton DIY’ers like me.   After just a few simple mods this player is sounding really, really good.

First some background on my experience with Oppo.  Feel free to skip this part.  Last year I spent considerable time modding the Oppo 970 with good but limited results.  I reworked the SMPS board with upgraded diodes and caps, bypassed the +3.3v, +5v, +/-9v dc lines feeding the DAC and opamps with 10uF poly caps, and cap-coupled the L&R DAC outputs to a set of upgraded RCA jacks.  This made it sound significantly better than stock, but it still didn’t compete with high end digital sources. 

This was brought home to me a few weeks ago when I visited Bob Levi, PFO reviewer and friend from the Los Angeles Orange County Audio Society.  I brought the 970 with me to compare it to some of Bob’s digital sources.  Bob has a stock Denon DVD-2200 that he uses as a baseline reference for entry-level digital.  He also has a Benchmark DAC-1 with Alesis CD Recorder as transport, a Modwright Sony 9100ES, and an EAR Acute CD player. 

My modded 970 clearly sounded better than the Denon.  The 970 had a sense of space, depth and midrange articulation that just wasn’t there on the DVD-2200.  Bob was impressed that I was able to get that much out of the Oppo.  Compared with the Benchmark/Alesis combo, it was a toss-up.  The Benchmark had better bass and was more extended and articulate on the top, but the Oppo had better soundstage depth and width and a more natural midrange.  Comparison to the Modwright and EAR players showed up the Oppo for what it was: a hot rodded entry-level player, not top-class digital.  The Modwright and EAR players made beautiful music and left the 970 sounding grainy, disjointed and muddled by comparison.  A very enlightening experience for me.

Enter the Oppo 980. At $169 it costs $20 more than the discontinued 970 but it has some changes that make it very mod-friendly.  Out of the box the player sounded bold and articulate but dark and closed-in, kind of like a well-recorded but highly compressed pop CD.  The black faceplate is much better looking than the 970 and it’s easier to load and retrieve discs from the tray.  The back panel now has a standard IEC (no ground pin) power connector so you can use any power cord you like.  Inside, the layout is like the 970 with a separate SMPS board off to one side, the main circuit board in the center and the transport mechanism on the other side.

The DAC in the 980 is the Cirrus CS4361 with eight analog outputs for 7.1.  The CS4361 only requires +5v for power instead of the +3.3v and +5v needed for the CS4360 DAC in the 970.  The BIG plus for this player are the voltage regulators.  Towering over a sprawling metropolis of SMD components are three TO220 size voltage regulators; a 7805 for the +5vdc DAC, and 7809/7909 regulators for the +/-9vdc opamps.  The 7805 and 7809 are fed from the same +11v line from the SMPS while the 7909 gets its own -19v line.

The first thing I did was bypass the opamp output stage for the left and right channels.  For each channel (L & R), I removed the 100uF electrolytic cap between the DAC output and the opamp input and put in a 4.3uf ERSE poly cap from the DAC output to a new RCA jack mounted on the back panel.  I then put a 10kohm load resistor between + and - of the RCA jack.  I finished it off by bypassing the 4.3uf with a .22uf PIO.

As for the power supply, seeing that 7805 regulator for the DAC got me thinking.  I already had a tweaked-out LT1086 based +5vdc linear PS that I built for my squeeze box.  So I decided to find out how that would sound powering the Oppo DAC.  I removed the 7805 regulator and replaced the 220uf and 10uf electrolytics next to the regulator output with equivalent Panansonic FMs.  I then wired the 7805 mounting holes for pin 2 (ground) and pin 3 (+5vdc out) to a 5.5mm power jack mounted on the back panel.  The final step was to plug the SB power supply into the jack and fire it up.

Result?  It works!  And it works very well.  The sound of the 980 with this mod just blows away the modded 970.  It’s dead quiet, like my squeezebox.  Music emerges from blackness and has an organic flow and integrity that the 970 just doesn’t have.  I haven’t broken this player in at all so I hesitate to say much more.  But I will say that powering the DAC in the 980 with a tweaked-out 5v PS has enormous potential for delivering great sound from this budget player.  Once the 980 gets broken in, it may be time for another visit to Bob’s house.

Russ

[Occam]

Russ,

Thank you for that very informative post!
You prompted a perusal of the Cirrus CS4361 PDF, and its one slick 6 channel DAC.
http://www.cirrus.com/en/pubs/proDatasheet/CS4361_A2.pdf

Its actually designed with the internal output stage having nominally enough grunt to directly drive the outside world. It appears to have substantially better drive capabilities than other DAC chips that others have previously used in passive, nekk'd output mods.   I'm unsure as to why Oppo chose to add the output opamps and the bipolar 9volt supply. Possibly drive, both current and voltage? From the pdf, I assume the dac could output 2.1vrms directly.

The way you investigated the benefits of that simplified circuit with an external regulated linear ps is really slick.

What are the output opamps are in the Oppo 980?

Thanks,
Paul

[Russtafarian]

I don't remember the output stage op amps.  They are SO-8 smd dual op amps and probably quite cheap. 

I ordered up a SO-8 LM4562 with the thought of trying that in the 980.  I lost my nerve when I saw how closely packed the surrounding smd resistors and caps were to the op amp.  I could just see one slip of the soldering iron dislodging and scrambling a half a dozen parts. 

[Woodsea]

You must keep us informed.  I think the 980 would be a lovely little project for me.  Please have all your thoughts, hypothese and testing done by the time my parents come to Havana, so they can lug all the part here.   

Thanks in advance! 

[poseidonsvoice]

Russ,

Thanks for your research. Very informative post! The LM4562's would be a nice choice if you can squeeze them in without destroying the player, however, overall it may sound better with just the capacitors directly from a voltage output dac.

I think the bees knees is what you have already done. Design a good 5V supply, forget about the opamps and just go directly with capacitor coupling to the outside world. Another more costly option would be to replace the output opamps with something of higher caliber (4562, etc...), but you'll need a well designed bipolar linear power supply for that as well. The stock SMPS supply would then concentrate its efforts on hopefully peripheral needs. It would be nice to find a schematic of the 980 though.

Thank you,

Anand.

[jholtz]

I'm curious about the 980 since Occam gave the CS4361 DAC a thumbs up. I have a 980 that I use for video only (it rocks!) and have a Zhaolu 2.5C that I've installed a Zapfilter discrete out put stage in that is connected to my Squeezebox for 2-channel. I installed the Zapfilter after shorting the caps, upgrading to LM456s opamps etc. and getting nice improvements but not the sound quality I was looking for. The Zapfilter takes this DAC to a whole different level, and IMHO, compares favorably to super high dollar equipment. Discrete output stages *DO* make a big difference.

Now for my question. If the CS4361 DAC has as good of sound quality as the CS4398 in my Zhaolu C, could a Zap filter be installed in the 980 with a digital input installed so I could use it as a DAC for my Squeezebox? Am I getting crazy here or is this a reasonably doable mod for someone with limited experience?

Thanks!

Jim

[Jon L]

Zhaolu 2.5C that I've installed a Zapfilter discrete out put stage

I wish I had another Zhaolu 2.0 with switchable boards with AD1852 and CS4398 to try with the Zapfilter.  I do have the Oritek Zhaolu, in which AD1852 clearly outperforms CS4398, but it's too bad the 2.5 and 3.0 Zhaolu's don't have the switchable DAC boads anymore..

[ted_b]

I own the Oppo 980 (as well as a Modwright Platinum Signature modded out Denon 3910) and use them for hirez 2 channel (Denon via tube analog) and surround (both for SACD/DVD-A).  Now, with my latest processor addition I've been playing around with the Oppo 980 hirez surround via HDMI 1.3 to my Onkyo Pro 885 processor (both DSD and PCM).  Would this slick mod you did theoretically improve the sound of the HDMI output too, or just analog 7.1 and 2 channel? ..thinking maybe the better power supply improve any output SQ?  Thanks

[Jampot]

Looks as though this player should support European (PAL) disks so it may be possible to buy in the States and bring home here to the UK. (Yes, Oppo seem to distribute it here but it's the old story - $1 = £1 ) I haven't previously come across an affordable player that will play UK and US disks (tried it with the Sony range) and also has composite video AND analogue sound out.

Does it look as though there is room inside to mod 5 channels for dvd-a / sacd output?

And is there any likelyhood (does anyone think) that any of the usual 'modders' may offer this without it breaking the bank?

Jim

[ted_b]

Both RAM Mods and Ric Shultz have been modding this player, and have posted here.

[Philistine]

Looks as though this player should support European (PAL) disks so it may be possible to buy in the States and bring home here to the UK. (Yes, Oppo seem to distribute it here but it's the old story - $1 = £1 ) I haven't previously come across an affordable player that will play UK and US disks (tried it with the Sony range) and also has composite video AND analogue sound out.

Does it look as though there is room inside to mod 5 channels for dvd-a / sacd output?

And is there any likelyhood (does anyone think) that any of the usual 'modders' may offer this without it breaking the bank?

Jim

I use the 970 for my Region 2 discs, it has both PAL and NTSC along with auto voltage sensing.  As the 980 has similar specs for voltage and PAL I would assume that it work fine in Europe.   

[Jampot]

Thanks Ted - I'll look them both up.

Phil, thats what I thought from the comparison page on the Oppo store website. It must use my i.p. address to devine I am in Europe and will only show me the European version of the machine with scart socket and price in Euros.

I have folks in NY and they have stuff from home (UK) including disks, and stuff bought there - otherwise I wouldn't have known there was a difference.

Jim

[BobM]

Does the 981 use the same DAC chip? What is different between it and the 980?

I have the 981 and even though I use it almost exclusively for home theater I might be convinced to try a few things inside.

Bob

[Russtafarian]

Wow! Quite a response.

If the CS4361 DAC has as good of sound quality as the CS4398 in my Zhaolu C, could a Zap filter be installed in the 980 with a digital input installed so I could use it as a DAC for my Squeezebox?

I'm in no position to compare the CS4361 with the CS4398.  All I can tell you is that by isolating the DAC from the internal SMPS and powering it with an external linear PS, the player sounds pretty damn good.  You could certainly install zap filters on the analog outputs of the DAC, but you'd have to figure out how to power them with an external PS. 

As for installing a digital input, that's way beyond the scope of what I could tell you.  The 980 does have a USB 2.0 port so you could connect a drive full of MP3 or WMA files and play them.  The down side would be that you'd be stuck with the Oppo's rudimentary GUI for navigating the music files.

Would this slick mod you did theoretically improve the sound of the HDMI output too, or just analog 7.1 and 2 channel? ..thinking maybe the better power supply improve any output SQ? 

The mod I did only impacts the analog outputs.  There is a separate +5v line from the SMPS that powers the video/HDMI circuitry.  Connecting a tricked out linear PS to that could very well improve HDMI.  I probably won't pursue that since I'm using the 980 primarily for audio.

Does it look as though there is room inside to mod 5 channels for dvd-a / sacd output?

There's plenty of room to mod all eight analog outputs if you're so inclined.

Let me make the disclaimer that bypassing the opamps and using only a cap between the DAC and the output jack does reduce output voltage.  The result is that the player may not drive long cable runs very well, may not work well with a passive preamp, and may not have enough gain to drive an amp directly.  But when plugged into a good preamp with gain, it works very well.

Russ

[Jampot]

There's plenty of room to mod all eight analog outputs

Thanks Russ.

Ric Shultz lists mods to the additional channels as an extra to his basic package so presumably he has done it before.

This sounds like a go-er. My main source is a Squeeze box these days, but the possibility of half decent multichannel for occasional use will be great, particularly since it will sit where the dvd player does now.

Jim

[Occam]

The Oppo 980 uses the ubiquitous NE5532a bipolar dual opamps for audio output.
As imitation is the sincerest form of flattery, I'll take some guidance from GBB's latest comments on modding  the SB3 -
http://www.audiocircle.com/index.php?topic=49342.0

From my (limited) experience, the National LM4582/LME49720 makes a wonderful drop in replacement for the 5532, with improved objective and subjective performance.

The SO-8 versions are -
LM4562MA
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=LM4562MA-ND
or the LME47920MA
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=LME49720MA-ND
which is the same but with numbering which jibes later released audio opamps

An alternative chip, with a slightly warmer presentation, would be the AD8599 -
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=AD8599ARZ-ND

Gary's SB3 signal path mod replaces the dac to opamp coupling cap with a BlackGate 10uf 50v type N and the opamp output coupling cap with a 4.7uf 50v type N. As the SB3 runs its opamp off a single +9v rail, the output coupling cap is required to remove the appox. +4.5v offset. As the Oppo provides +-9v rails, hopefully, its opamp output can be directly coupled.

Russ, could you let us know whether the opamp outputs are directly coupled or via a capacitor?
Also, whatever electrolytic coupling caps are used, could you tell us what they are?

Gary seems to much prefer his LM4562 output SB3 to his mod of taking output directly from the dac. Dunno how this would play out on the Oppo.....

FWIW,
Paul

[Russtafarian]

There are 100uf electrolytic coupling caps from the DAC to the opamps and from the opamps to the output jacks.

The hardest part of the mod is disconnecting and reconnecting the thin ribbon cable from the transport to the main board without mangling it.  I mangled it when I worked on the 970, and despite my care it looks like I mangled this one too as the player will only read CDs now.  I'll have to call Oppo on Monday and order another one.

Russ

[Russtafarian]

Here are some updated notes on my Oppo 980 mod.

First a brief overview of my system for context.  Sources are a SB3 w/ DIY linear 5v PS, VPI TT/Dynavector Cart for vinyl, and whatever shiny disc spinner I happen to have at the time.  Preamp is ARC LS14, mainly for the phono stage as the line stage is good but not great.  Amps/speakers are a pair of Quicksilver monos with 6550s driving VMPS RM30s.  Stereo subs are a pair of 15” folded cabinet dipoles fed by an Outlaw ICBM xover, a Behringer digital EQ, and a Hypex 200 w stereo amp.  Surround provided by a pair of Magnepan MMG-Ws driven by a Hypex 90w stereo amp.  All low current gear plugged into my four circuit, eight transformer uber-Felicia.  All amps plugged into an Equitech 2Q BPT.

Transport Issue

When I last posted I mentioned that once I reassembled the Oppo after the mod it wouldn’t read SACDs or DVDs.  Turns out it was a faulty transport mechanism.  With a new transport in place the 980 works just fine.  No problems playing SACDs and DVDs.  My guess is that the original transport never did read SACDs and DVDs but I didn’t bother to test it before I started my mod. Doh! 

Don’t do what I did.  Test your player before you start hacking away at it.

Transformers

Bypassing the opamp output stage in the Oppo cost me a lot of gain and I really had to crank up my preamp to deliver enough signal to the power amp.  On a lark, I inserted a pair of Lundahl LL1678 moving coil step up transformers between the Oppo and my preamp.  The transformers are set for 14 dB of gain.  I fully expected the transformers to overload, but they didn’t and it sounded good.  Next I disconnected the preamp and ran the Oppo through the transformers directly into my amp and used the Oppo’s RC for volume control.  This gave me all the gain I need and it sounded phenomenal!  Speed, clarity, dynamics, and dimensionality that the preamp just can’t deliver.  I put my ear right up the speaker and hear no noise, and this is with a tube amp in the system.  I can’t get over how palpably REAL this sounds.  I’ve got to get a few others over to listen to this to make sure I’m not deluding myself.  I ended up mounting the transformers in a box with a three way source switch so I can run my Oppo, SB3, and the ARC phono stage through the transformers to my amp. 

HDMI

I listen to a lot of multichannel SACD/DVD-A music, so Ted’s comment about using the 980’s HDMI output into an Onkyo processor for M-C hi-rez discs piqued my interest.  Kal Rubinson wrote about the same thing in his Music in the Round column just posted on Stereophile.com.

So I borrowed a friend’s Denon AVR2807 receiver to experiment with.  The 2807 has HDMI 1.1 so by going Oppo HDMI > Denon preamp out > amp, DVD-A and SACD surround is decoded as PCM in the Denon and sent on to my amps/speakers.  I had high hopes for this setup, given what I’ve read about the benefits of Audyssey room correction and a 5.1 hi-rez digital connection. 

I went through the Audyssey setup and got everything configured.  It did work, but it didn’t sound all that great.  Whatever benefits that were gained through the Audyssey DRC and the HDMI connection were lost due to an increase in digital grain and an overall lack of transparency compared to the Oppo analog > transformers > amp setup.  This is probably more of an indictment of the Denon receiver’s line output stages than anything else.  I’ll certainly try this again if I can get my hands on a high quality HDMI 1.3a processor to see if I can get a better result.  For now, analog 5.1 from the Oppo sounds much better than the HDMI approach.


Bybees

A few weeks ago I got a hold of four slipstream bybees to experiment with.  Putting one bybee on the +5v pin of the linear PS plug worked really well.  It lowered the perceived noise floor even more without dulling the sound.  Putting bybees in the analog signal path didn’t work for me.  The bybees seamed to soften leading edge transients and added a weird energy to the lower treble.  Removing the bybees from the signal path put back the transient snap and recaptured the open, organic character in the top-end.

Overall Listening Impressions

The modded Oppo 980 (mods as described in my first post) sounds really good!  As mentioned above, I use the Oppo remote volume control for an ultra-simple and clean DAC > Cap > Transformer > Amp signal path.  It sounds better than my SB3 playing back the same tracks.  It’s quieter and reveals a whole layer of low level detail and textures that the SB3 misses.  The music has a very organic quality to it with little, if any digital etch.  The soundstage is very open and dimensional, though not as expansive or rich as the best players I’ve heard.  SACD performance is on par with CD, maybe a little better on some discs.  Must be the PCM conversion because the very best SACDs are not as delicate and expansive as I remember them sounding on my Sony NS999ES (r.i.p.).  SACD and DVD-A multi-channel music really sounds phenomenal on this player.  The Oppo fully delivers on this front. 

So overall, I’m pretty happy with the results.  No, this is not a world class digital player.  But it is very musically satisfying given the cost and effort I put into it, and should keep me happy until next digital revolution sweeps over us (in about 3 to 6 months or so).

Russ

[ted_b]

Great update.  Thanks.  So, to reiterate, your love of the Oppo's 5.1 analog outs is worth noting; they currently consist of transformer-enhanced fronts that have new and/or bypassed op amps, and the center, surround and sub outputs are stock, right?

[mcgsxr]

Interesting read, thanks for taking the time.

Can you take some pics of the subs?

I understand that you are using the DIY PS for the SB3, is the SB3 itself stock?

Thanks,