Cheers Ian! How r u?
it's alive againjust fixed it yeasterday!
the problem was in the resistor near the cap I shortened...sad thing is that I checked 3 of them right after all that had happened and forgot to test the other one that is between two 470uf caps...Anyway, now Restek is working fine
I'm good thanks! Excellent news!!! I remember how I felt when mine was in a state of flux
Are you staying with 4 total or going up to 8? The increase should make a nice difference. Not sure how the Elna's will compare to the F&T's is used. You need to be a little careful with the opamps in the power stage. I blindly rolled mine. There is another thread I started relating to the opamp changes and generally my change is not met with approval! I see it as an upgrade and it worked for me so the 10HA's are staying. Burson discrete opamps did not work here!
http://www.diyaudio.com/forums/solid-state/145507-opa604-again-but-offset-18v-2.html#post2455948
Still need to decide which caps to chose for:
1) 470uf psu caps
2) 10uf PreAmp section
2) 470 & 220uf power amp sections
I was thinking that for 4 x 470uf PSU caps some decent BC could be chosen, for instance. I guess that Preamp section desperately needs to have Silmics
I wouldn't pay an much attention to the value's fro rail caps. I replaced most of my pre amp with 100uF Rubycon ZA and threw 4 220uF BG's in there for good measure too! The rail caps on the power stage were replace with FM's (borderline voltage tbh) 470uF were upped to 1000uF and the 220uF to 470uF. The theory being that they will be more able to maintain the rails under demanding load conditions. FC's may be a little brittle sounding but I beleive they settle well. wanted a smoother sound which is why I went with FM's. I've not used Tonerex before but I've looked a few times!
you are trying to say that it's dangerous to use LME49710HA instead of OPA604 or better not to use at all?
Btw did you make a separate comparison by listening only these two OPAMs?
Stayed with 2 x 12000uf on the rails of each channel. It's slightly more than the original 2 x 10k uf and could save some space in the amp
One more cap related question did you leave these 4 axials 22uf 63v in the beginning of power amp's section?
Btw did you make a separate comparison by listening only these two OPAMs?
Stayed with 2 x 12000uf on the rails of each channel. It's slightly more than the original 2 x 10k uf and could save some space in the amp
One more cap related question
did you leave these 4 axials 22uf 63v in the beginning of power amp's section?
I use the LME49710HA without issue. The sound is definately better with them. The bass is tighter and the overall sound is less wooly. I very much like this opamp for detail, speed and accuracy.
If i'm honest, I don't fully understand the circuit. There are a few who do in that thread I linked to. They say use the 604. I say the 604 is rubbish and the LME works fine for me!!!
With respect to the axials, I dont remember changeing any of them but that doesn't mean I didn't!! lol
Things are settling a little more for me now following my housemove. I have a workbench again! YAY!!! So hopefully I'll get a chance to poke around in there again soon. I fancy trying something different with the Pre section and volume control!!!
If i'm honest, I don't fully understand the circuit. There are a few who do in that thread I linked to. They say use the 604. I say the 604 is rubbish and the LME works fine for me!!!
With respect to the axials, I dont remember changeing any of them but that doesn't mean I didn't!! lol
Things are settling a little more for me now following my housemove. I have a workbench again! YAY!!! So hopefully I'll get a chance to poke around in there again soon. I fancy trying something different with the Pre section and volume control!!!
I bet it was the 2nd thing you set up after the hi-fi!!
I needed to find a desk to use in the new room. Lucky for me, I won a very nice, very large desk on eBay about 3 days after I moved in. Invested 99p et voila......a workshop is born!!!
Had I been in posession of the desk from day 1, I think you'd have been right Simon!!!
I'm really looking forward to getting all the crap out so I can get on with some stuff. It's going to be great having a dedicated workshop/ build/ test room!
Congrats Ian 
lucky you are!
I will go ahead with LME49710HA and later write some thoughts about the comparison of these two opams.
Yet already some time looking forward towards Radiant CD that could be a great matching pair for the amp. It's also more than 15 years old and uses TDA1541.
lucky you are!I will go ahead with LME49710HA and later write some thoughts about the comparison of these two opams.
Yet already some time looking forward towards Radiant CD that could be a great matching pair for the amp. It's also more than 15 years old and uses TDA1541.
Congrats Ian
I will go ahead with LME49710HA and later write some thoughts about the comparison of these two opams.
Yet already some time looking forward towards Radiant CD that could be a great matching pair for the amp. It's also more than 15 years old and uses TDA1541.
OMG!!!!! I have 4 1541 based players and 3 1541 based dac's! I didn't realise restek did a 1541 player. I WANT one NOW!!!!!
Yeah!!!!
One in black went on eBay just before xmas. I want the next chrome one!
Its a cdm4 mech and an S1 TAD1541 and it will be mine!!!
btw, there are three different Radiant modifications. One of them has only one power button on the front plate that seems to me very cool, I assume it's the 1st one that uses"1 x PCM56P-J ?SM5807". Moreover, some models have external power supply, others internal. Anyway didn't find any decent information in the net, so don't know precisely.
Fu*&%$ !!! Amp is dead again Slightly moved main psb that wasn't tightened with the bolts and saw some sparkling fire on one of the resistors (display pbs, pls see att). Turned it off immidiately, checked the res, it was ok, hence I turned the power back and lucky I was understanding that it still works fine. Then wanted to be sure and check all the other components and touched one cap (220uf) on the same display psb... Again immidiate protection has turned on and it doesn't turn on anymore now in the end... The more confusing fact is that there is no voltage anymore on the transformers' output...
Fu*&%$ !!! Amp is dead again
Slightly moved main psb that wasn't tightened with the bolts and saw some sparkling fire on one of the resistors (display pbs, pls see att). Turned it off immidiately, checked the res, it was ok, hence I turned the power back and lucky I was understanding that it still works fine. Then wanted to be sure and check all the other components and touched one cap (220uf) on the same display psb... Again immidiate protection has turned on and it doesn't turn on anymore now in the end... The more confusing fact is that there is no voltage anymore on the transformers' output...Attachments
of course, I did
frankly speaking I didn't make any separate listening tests regarding these new opams as made a few modifications to my CD as well (Good old Philips CD350 with 2 TDA1540p. I did replaced all the caps to silmics and axial Philips, removed SAA7030, installed mains socket with filter, good rhodium RCAs, 2132 OPAMs). Moreover would like to recap all the Restek initially and then feel the difference even not actually listening to it
Anyway, once I turned the music yesterday i was pretty impressed by new opams (thanks for recommendation) and SAA7030 removal! Certantly I felt the difference, though didn't make some special testing with various CDs...To my mind it's more rapid and open, I felt more energy on my favourite bands like Disturbed, Slayer, Korn, Metallica and others.
next step is to recap all the shi*&% in the amp. Then I'm planning to decouple TDAs in my philips with Wimas mkp (already bought, they are really huge) and install separate clock instead of original quartz.
Btw, Ian, how do you think is there any point changing all ceramic resistors?
frankly speaking I didn't make any separate listening tests regarding these new opams as made a few modifications to my CD as well (Good old Philips CD350 with 2 TDA1540p. I did replaced all the caps to silmics and axial Philips, removed SAA7030, installed mains socket with filter, good rhodium RCAs, 2132 OPAMs). Moreover would like to recap all the Restek initially and then feel the difference even not actually listening to it
Anyway, once I turned the music yesterday i was pretty impressed by new opams (thanks for recommendation) and SAA7030 removal! Certantly I felt the difference, though didn't make some special testing with various CDs...To my mind it's more rapid and open, I felt more energy on my favourite bands like Disturbed, Slayer, Korn, Metallica and others.
next step is to recap all the shi*&% in the amp. Then I'm planning to decouple TDAs in my philips with Wimas mkp (already bought, they are really huge) and install separate clock instead of original quartz.
Btw, Ian, how do you think is there any point changing all ceramic resistors?
I'd say thats very much what I found. If you detect any harshness at all, I'd expect this to subside as the opamp burns in which it will.
LArge Wima MKPS is what I was running in my player until I build my new dac section!
You should investigate a little bit on the clocking. Are you sure you want 16.xx and not 11.xx master clock? Also, you should trace the clocking out so that you run direct feeds as far as possible rather than cascading via devices within the player as this too has a profound effect.
Any caps at all in the signal path, I'd change. Silvered mica are excellent for filter caps and any DC blocking will benifit from a change.
I meant to say that in the restek, there are 2 dc bloking caps on the input to the power stage. I replaced mine with some MKS2 22uF poly caps which unfortunately are now obsolete. This is a must for this amp! def get rid of all elco's in the signal path.
I'll link you to another thread because another user has some he purchased before they ran out!!!! They are tiny BTW 5mm spacing and fit in the original holes.
http://www.diyaudio.com/forums/swap-meet/178855-new-22u-16v-wima-film-caps-mks2-xl.html
In the diagram, they are 22uf Bi polar elco's bypassed with 1uF poly caps. I think mine were similar but not exactly the same.
Hi Ian,
thanks for the link
didn't actually get which elco caps you are talking about. Do you have a picture of these 22uf caps?
As to the clock as far as I know I need to stay with Philips's 16.9344 frequency or other value multiple to that (it's 4.2336 written on the quartz of mine). Moreover this clock module simutanuously supports 4.2336 MHz accoring to seller's description, so I hope it would work with my CD350. Later planning to install separate trans for that.
thanks for the link
didn't actually get which elco caps you are talking about. Do you have a picture of these 22uf caps?
As to the clock as far as I know I need to stay with Philips's 16.9344 frequency or other value multiple to that (it's 4.2336 written on the quartz of mine). Moreover this clock module simutanuously supports 4.2336 MHz accoring to seller's description, so I hope it would work with my CD350. Later planning to install separate trans for that.
The caps are marked on the pic below.
In the service data, there are no caps shown on the gnd connection.
In my amp, on the signal input, there was a 22uF elco bypassed by 1uF film. The 1uF has been removed and the 22uF elco is replaced by a 22uF film (red block in the pic) I did this for both the signal and gnd.
In the service data, there are no caps shown on the gnd connection.
In my amp, on the signal input, there was a 22uF elco bypassed by 1uF film. The 1uF has been removed and the 22uF elco is replaced by a 22uF film (red block in the pic) I did this for both the signal and gnd.
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