opa 627bp in MHZS cd33

Hi Viewer,

My first step will be changing the 3 Brown & 1 Green Cap + the TWIN cap next to the OPAMP + the one in front of the RCA socket and finally the one next to the socket.

The clock will be the second stage.

Will for sure post the photos ...

I think you once mentioned that the PCB of the CD 33 is not that "solid", it can easily breaks ... is there any precautions I need to take?

hi alfcat,

i hope to hearing the result of the upgrade cd33 soon. and post it  to sharing with the  members.


thanks.

Hi Viewer,

My colleague said what you used are very HIGH Grade and expensive. The quality of sound you get from the CD 33 should be very very good.

I will shop around for the CAPs by the end of this week after my BB finished her final exam. Need to watch over her for the coming few days.

Will plan for what I get at present as I think it will be better for me to go step by step and don't try to do everything in one time.

My Bendix tubes got delayed. Probably won't arrive until Friday or so. Will tell you what they are like after I test them out.

See you.

Hi, alfcat,

I also upgraded the OPAMPS caps to Elna Cerafine e-caps.
the best is black gate e-cap but elna is cheaper than black gate,
the sound is 80% close to black gate, so it is very good e-caps in my view.

three green colour e-caps are Nichicon Muse e-caps old stock brand new.
I buy it in http://www.soundexplorer.com/home/home.htm
The brown caps is Elna A3 e-cap for audio.
Those e-caps around HK$25 each.
The rating is same as the original rubyon e-caps.
I have use panasonic FC grade e-caps. not good result.

Thanks

No wonder ... I thought the photo got problem (Black --> Red)

And you upgraded the OPAMPS caps as well ...

So what BRAND and ratings are the three Green & 1 Brown CAPS? Did you use Panasonic or ...

Thanks

Hi alfact,

beacuse finally i used black gate non polar e-cap. so the photo which shown before are use black gate normal garde.(balck colour).

What are the 3 Green + 1 Brown CAPs LEFT parallel to the Tubes. I think you suggested us to replace the original as the originals are not for Audio Use. Is that correct?
ans: yes.

Thanks

Hi Viewer,

My Hi Fi Fan colleague believes that the "distortion" in the High Frequency part is caused by the Caps. He suggested me to change the CAPs as well.

I followed your messages and your photos and see if I have matched the items you mentioned correctly.

For the PCB on TOP Right of the Transformer. You used TWO Jensen 0.22uf/630v (Silver) --- located at the Left Hand Side of the PCB.

Then you use a 0.22uf/630V Jensen Pure Copper Foil (lower RIGHT to the TWO Silver Jensen).

On the TUBES PCB, you use a Jensen 100uf/150V (right underneath the RCA heads). Then you use Jensen Copper Foil 033uf/630v (next to the OPAMP).

I can't find the Black Gate non polor 10uf/50v (which you said is RED).

What are the 3 Green + 1 Brown CAPs LEFT parallel to the Tubes. I think you suggested us to replace the original as the originals are not for Audio Use. Is that correct?

Thanks for the call.

My other two colleagues are now waiting for my test on the OPAMPs. They are going to modify their CD 33 as well.

We just ordered 3 matched pairs of Bendix 2C51. Hopefully it will arrive next Thurs or so. Will compare them with the WE 396A and see how well these 195x produced tubes are.

I normally do the ordering from them, buying the necessary items from USA. Buying from eBay is sometimes risky. I been trapped a few times as well.

We are teachers; that is why we will have more spare time after next week as exam is going to start .... :wink:

Will go to Ap Liu Street on Monday as I will be off by 2pm

Keep in touch.

hi alfcat,

would you mind leave you tel to my e-mail
audioviewer@yahoo.com.hk

i will contact you soon.

thanks.

Hi Viewer,

I have that photo but I don't know HOW you do it .. ha.ha.. I am an idiot in this, sorry.

You need a IC board or something? How do you match the TWO 627AM and the TWO white Film cap onto that SIO 8?? socket

Please advise. Thank you

Hi alfcat,

close up photo :

http://www.hififever.com/forum/files/thumbs/t_p1010098_155.jpg


Thanks.

good morning, alfcat:

those white "film cap" added is for filter use, it let the sound smooth..
this 2to1 IC socket can get it from vocaviteaudio.com cost $10 to $15.

It does't matter. we are diy.
would you mine to post you modified MHZS CD33 for sharing.

Thank you for sharing.

Hi Viewer,

I can't find a close up Photo of your OPAMP. I think you have use somethiing like an IC socket as you have those white "film cap" added as well.

I gone through almost all the pages here .... Do you think you can explain how you do it here again as I am totally ignorant in this.

Sorry for the trouble. Many thanks.

hi alfcat

You say 637 only have sound from one channal. are you put one bp637 in IC socket. It should be wrong.
The op637 is 單聲道, so much two bp637 in ２轉１ IC socket like my posted before.


Thanks.

Hi Viewer,

Also one PROBLEM I just realised. As it is getting dark and the environment is quiet, I "think" the High Pitch is a bit toooo high with the 2107. For musical instruments, it is acceptable. But when I play 陳潔麗 disc .... it is kind of distorted when it comes to the very high pitch.

I am not sure what caused the problem. Will double check with other people to see if they have the same feeling as I do.

Will keep posting the results.

Oh my goodness, I have to sell the 637 out then ... sigh.

BTW, from the photos you posted, you seem to have TWO 627AM installed. Why is that?

Hi alfcat,

Because the gain of OP637 is great than 5, others is under gain 5.

so MHZS cd33 cannot use op637. OP627 is no this problem ,because its gain is under.


thanks.

Hi Viewer,

I have tried out the OPAMPs in the following sequence:

1. OPA2228 to replace the OPA2604. Sound Clarity greatly improved. Like
    in singing, you now 咬字清楚了很多.

2. OPA2107 to replace OPA2228. Even BETTER sound clarity, starts to hear
    poor recording effects (e.g. singer not so ... good in singing). The
    "dimension" of sound improved.

3. OPA637BP ... PROBLEM! After I plug the 637BP into the socket, there is
    sound coming from ONE channel only. What is wrong? This chip cannot
    be plugged like the 2228 or the 2107? Please advise .... HELP!!

I cannot access this forum at around 9pm ... should have replied you earlier .....

HI ALFCAT,

PLEASE LET ME KNOW THE SOUND OF 637 and 2107.

THANKS.

Hi alfcat,

I solder the old ones out completely, and clear the solder points.

Thanks.

Hi Viewer,

My OPAMPs just arrived today as expected. Will try to use them to replace the original one by one to see / hear the difference. As there are construction work right opposite my home, need to wait > 7pm then I can have some quiet time to listen to music.

Still trying to figure out all those components you mentioned. As stated earlier, I am totally novice to electronics ... but I will see how many of those I can guess right.

When replacing the caps, you solder the old ones out completely or "cut at their feet" and then mount the new one on the "old" cap's feet?

Hi, alfcat

1. Changed the 2 solen scr cap 0.22uf 630v to jensen 0.22uf 630v copper foil
(golden colour in my photo) around $440. brand new, you can find 2 hand market around $300.
2. Changed 0.33uf of M-cap to jensen copper foil 0.33uf 630v siliver colour) which beside of the tubes cost around $250.
3. changed robyon 10uf/100v which behind of the tubes to Black-gate non polor 10uf/50v  (red colour ) around $90.
4. changed the e-cap of power supply.
5. lastly, add re-clock system bule colour pcb , which shown in my cd 33 photo costs around $200.



thank you for sharing.

Hello Viewer,

My OPAMS will probably arrive these few days and so will my Bendix 2C51 tubes.

I checked back the photos you posted and realised that you have modified your CD at least two times. I am now planning for the next stage of changing the caps. Where would you suggest me to start off with. I would say my budget is just HK$ 2K maximum and I like Vocals more.

Please advise. Many thanks

hi alfcat,
welcome.

Hi viewer,

Wa .. you have been modifying your CD 33 since last year! I go back to the FIRST page and realised that you spent so much effort to test things out and share all these findings with us. Great JOB!

I will consult you more as I further mod mine in the coming months.

Hi Viewer,

I went to vocativeaudio some weeks ago. Many of their products are out of stock and they need to order for me.

My stock of 2227, 2228, 637 and 2107 will arrive next week. I will try them one by one. Then I will see if I can get the 627AM from diykits. Hope that I can get from them.

Many thanks!

Hi alfcat,

You can buy it in HK at the following shop:
it only have 2nd hand, so price is cheap.

http://www.diykits.com.hk/
http://vocativeaudio.com/

Thanks.

Hello Viewer,

Thanks for your information. I can get hold of 2227, 2228, 2107. For the 627, I only have the AP one but wasn't able to get the AM one. Where did you get it and how much?

Hello KK Sir,

How do I test the wave distortion? I think you mentioned it once somewhere along the thread but I can't locate it now. Please advise. Many thanks.

hi kk sir,

i have not HA5112 from Harris, so no comment on it.

where can buy and how much ????

thanks.

How about HA5112 from Harris ?

hi alfcat,

go ahead to change opa627 am (metal case) you will found many detail from the sound before. and stronge bass.

because i test the some IC before as follow:

NE55345.
AD797 METAL CASE
OPA2228
OPA 827
DY2000
OPA 2111
OPA 2134
OPA134
OPA627BP AND
OPA627AP

OPA627AM IS TYHE BEST IN MY FEELING.
thank for sharing.

Hi,

I purchased a CD 33 a month ago and had been listening to it since. I just use a Pioneer AV Receiver 1016V-s to drive a pair of DIY ProAc speakers.

Last week, I got a "matched" pair of WE 396a (which cost around HK$ 600) and installed them into the player.

The vocal gives a very significant improvement over the original tubes. I also asked my wife to sit down and as an amatuer, she agreed that the WE tubes do give a big difference!

I am glad that there are so many of you sharing your DIY / Modification here. I am now going for the OPAMPS. Will see how signficant they are.

Hello,

There is something I don't understand. What is the meaning of OPA627 (plus BrownDog)? I know what a OPA627 is .. but can anyone tell me what is (plus BrownDog)?

Many thanks

WINDWSS, newfan,

Remember check your MHZ-33/66 have no bug (waveform distortion) before starting your mod.

KK.Ho

newfan,

For this cd33, i will suggest little mod is enough, try don't touch the e-cap, since the PCB is not s reliable, it may give u a lot hectic. My friend and i is suffering a lot.

Recomended minor mod:
1) change tube
2) change OPA - 627 is quite suit cd33
3) change the 0.22uf/630v cap at power supply & near the tube.
4) If really wish to change e-cap then change the 100uf/100v & 100uf/160v to better cap like blackgate, i think that will do.

Mcap silver obviously better than mcap zn. Mcap silver when compare to jensen Cu in oil/ audionote cu in oil is different type of sound. If u like vocal then jensen/audio note will be more suitable.

Hi everyone,

I'm new to this site so please forgive me if this is a poor post.

I've looked through this great thread a few times and I'm looking to upgrade my CD33....

AD823 and OPA627 ( plus browndog ) on order and looking for some WE396As.

Its the Capacitor bit thats not so easy. I have a few questions and would be most gratefull if anyone can help :-

* There seem to be 5 that are being replaced ..the two power - one tube and two uptput. Are these the best to start with ?

* They are 0.22uf and 630v other than the tube ( 0.47uf )...do I have to replace with these values or can I use higher uf figures and voltages ?

* Will MCap Supremes/silver/Jensens etc give much noticable improvement over say MCap ZNs ?

* Anyone know a good online source for these CAPs in the UK or has cheap postage to the UK ?

Sorry for the long post folks, hope you can help.

By the way I agree this is a cracking unit even in base form...much better soundstage detail and base than my Zhaulo 2.5 !

many thanks everyone

Hi, mike,

So far in the market in malaysia, for KSS-213C &213Q i only can get the china made product!
last several month i just just replace the cd pick-up... anyway for kss-213Q use in cd-33 so far 2 of my friends who use it don't have problem yet. So good luck to u as well!

u r right, there r a lot fake product from china and sometimes it is hard to know it from the packing. As we all know they are a lot of oversea brand have their factory in china, thus even for panasonic FC cap u can see diifferent type of packing/construction of the lead. sanyo os-con in china product is with white print but the same cap sell in farnel is in gold print work (the outer plastic cover quality look better).

[quote:780bfb31ef="WINDWSS"]hi mike,

nice to hera from your sharing on modification.

By the way how much better the opa2107 compare to opa2132? How about comparison with opa627Ap? just a bit supprise the opa627 is not in your future testing list, is there any special reason?

AD797 seems not as good as opa627 in cd33 (my friend's comment after using it)

By the way, it seems that a lot of people like to use panasonic FC, but i personally feel that it is too soft n bass a bit loose, can improve a bit at high frequency when bypass with ROE mkp/mkt i prefer to use BC(Formerly philips) e-cap : )

kindly share with us after your testing on various opa and other modification. Thank you!

SS[/quote]

Hi WINDWSS,

2107 has a very similar sonic signature to the OPA627 and also has the advantage of being a dual channel chip (dil8) It is slightly less chocolaty sounding than the 627 and I have loads of 2107 so seems logical I use them  

This KSS-213Q pickup concerns me a bit, it says "SONY" on it but I know Sony don't make such a pickup. Also, most of the capacitors used look like fakes to me and the so called "OPA2604" also looked like a fake. Is this quite common with some Chinese equipment? I have also read that the Chinese made KSS-213Q can be pretty unreliable (either last quite long or stop working pretty fast) is there any drop in replacement that can be used? It certainly looks like quite a flimsy pickup to me.

Again, the reason I use Panasonic FM is because I have hundreds of them, I also like the sound of them which is why I use them in all my Musical Fidelity Mods http://www.rock-grotto.co.uk/xcanpropage.htm members of my forum also seem to like them http://rockgrotto.proboards39.com/index.cgi  I have a few ELNA cerafine I will fit in strategic places in the CD-33 but really don't want to spend too much time on it to find the laser breaks down after a short period.... any info you have on the KSS-213Q would be most welcome.

All the best.

Mike.

hi mike,

nice to hera from your sharing on modification.

By the way how much better the opa2107 compare to opa2132? How about comparison with opa627Ap? just a bit supprise the opa627 is not in your future testing list, is there any special reason?

AD797 seems not as good as opa627 in cd33 (my friend's comment after using it)

By the way, it seems that a lot of people like to use panasonic FC, but i personally feel that it is too soft n bass a bit loose, can improve a bit at high frequency when bypass with ROE mkp/mkt i prefer to use BC(Formerly philips) e-cap : )

kindly share with us after your testing on various opa and other modification. Thank you!

SS

Hi Guys,

I bought an MHZS CD33 a few days ago and came across this excellent thread when doing a Google search. I wasn't too happy with the sound of the unit in stock form finding it rather "hazy" and vague sounding. I have started modding it and so far have replaced all of the grotty 1N4007 diodes with ultrafast UF4007 types..... whilst I was under the bonnet I replaced some of the caps with Panasonic FC / FM types and will eventually get round to fitting Panasonic FM throughout the unit.

Popped in an OPA2107 and fired her up.... you know what? chalk and cheese, the improvement is VAST with the sound now being extremely open, spacious and with absolutely subterranean bass... astonishing improvement (not a difference but a marked improvement) I've got a feeling the stash of 1N4007 were adding a bit of grunge to the sound and the OPA2604 probably not the optimum chip for the job.

I can't wait to hear this puppy with half decent output valves, hardwired output connections, Ultrafast diodes in the PSU section, more capacitance, damping... etc. etc. etc. This is a true tweakers dream and @ £180 (or cheaper) an absolute bargain! What price can you buy a CD33 for in China?

One helluva CD player for the money though and one I know I'm going to have a lot of fun with, not only can you opamp roll to tailor the sound to your own ears you can also valve roll.... PCB's are quite easily removed from the chassis too (a few screws) so you can whip either of the PCBs out in a couple of minutes and go to work on them should you want to go further than simply opamp / valve rolling... I'm going to have with this puppy  

Other opamps I'm going to try are AD-843 (on brown dogs) AD-744 class A biased (on Brown Dogs) OPA602 (on Brown Dogs) AD-797 (on Brown Dogs) AD-8620, AD-823, AD826, OPA2227, OPA2228 and my current favourite audio chip the LM4562 (superb audio chip!)

I'll visit this thread from time to time and will post pictures..... great forum you guys have  8)

All the best.

Mike.

H3D,

Fyi, when i start modification i had set the target to use only cheap &nice part, thus i don't have much idea on expensive part......

h3d,

Sorry since never use the 6385 so can't give comment.
Only know the price is a large difference!!!! ~20x different in cost.
And the sound cannot be 20x better : )

i undersatnd u have 6385 then u just spend <USD 10/pc to get the bendix then make comparation to share with us : )

i personally prefer eclipse pioneer than bedix even they construct in the similar way....

Hi Windwws

Do you know if there is a big difference between the Bendix 2C51 and the 6385 type?

H3d

[quote:2899a3ea8e="Abhader08"]windwss,

TL071CP is from my 8000P power amp. there are two ICs which located one in each mono circuit, total have two ICs. if OPA627 can be used then i might probally change to it.[/quote]

If that's the case most probably u can use the 627. just test the voltage in your TL071.

the 627 is +/18v = 36v(rail to rail) if not mistaken.

last weekend i had replace the balck negative(resevoir) of 8000A with Jensen in my friend's amp. It is fantastic... sweet , warm vocal with decend detail.....the improvement of vocal is much more than using WE396 in CDP.....

[quote:e177de385f="h3d"]Hi everyone,

Last week I did a comparison with a Arcam CD92. My sound was just as transparant and clear. His was a bit warmer. The differences were so small I was glad I paid a third of his price.

Yesterday a comparison with a modified Pioneer DP-S901. this one I clearly won. More clarity, better placement of the instruments, more high. I think because of the tubes.

A question to WindWWS:

You stated that eclipse pioneer tubes were the best for an acceptable price. Can you tell me where to  find them?[/quote]

H3D,
I purchase it from USA, i actually intended to purchase again but unfortunately the supplier reply me today that they no longer have the stock.

windwss,

TL071CP is from my 8000P power amp. there are two ICs which located one in each mono circuit, total have two ICs. if OPA627 can be used then i might probally change to it.

[quote:98beba39ba="kin111kin"]老爺機,金仔E202,飛記cd950(OPA627BP*4,換電容和1ppm clock),AR 11
電腦用安橋聲卡>麗特DAC-AM(OPA627BP*+4OPA627AM*4,換電容和1ppm clock)>NAD3020E>CHANIO(換分音電容,箱內接線)
雖然全部老爺cheap機,但都好滿意!
聽講隻Musiland MD10好勁,CD66勁摩$5000元後都輸條街,而且還未摩改,唔知LITE 72(一聽難忘版)同佢有無得輝?我用緊LITE DAC AM,同PHILIPS CD950只能打成平手[/quote]

Hi kin hing

as I remember the chip use at Onkyo sound card is C-media, its sound quality is crap, and its digital output is a joke, full of jitter, try change a better one sound card and you will have great improvement

Hi everyone,

Last week I did a comparison with a Arcam CD92. My sound was just as transparant and clear. His was a bit warmer. The differences were so small I was glad I paid a third of his price.

Yesterday a comparison with a modified Pioneer DP-S901. this one I clearly won. More clarity, better placement of the instruments, more high. I think because of the tubes.

A question to WindWWS:

You stated that eclipse pioneer tubes were the best for an acceptable price. Can you tell me where to  find them?

WindWSS,

One more, Marantz PM17 amplifier with HDAM buffer

KK