Quote:
Originally Posted by NRG
How is it modded Neal? I have a pre2 also. Circuit is unmodded but I've replaced all the components.
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Quote:
Originally Posted by NRG
How is it modded Neal? I have a pre2 also. Circuit is unmodded but I've replaced all the components.
Well it's not really a preII anymore, CD and AUX input go into a cathode follower and the phono input goes to the volume control direct IE passive.
I tried cranking the volume all the way up today and I only get a tiny bit of fizzle through my speakers. I had to put my ear right next to the tweeters to hear it. However based on the experience I've just had trying to re-solder the caps on the via's between the ribbons I personally wouldn't recommend soldering to them unless you're absolutely sure you won't be changing the caps in the future. I say this because despite being extremely careful I managed to lift the PCB track from the right hand via. :doh: They're very delicate. Personally I think soldering the caps to the holes where the right ribbon connects to the front board is better. That way you're still removing the ribbon and a fair bit of PCB track out of the signal path but you've got proper holes to solder one side of the caps to. Obviously you'd have to chop out a bit of ribbon but that's much easier to replace than a knackered via.Quote:
Originally Posted by MartinT
Seen as I no longer had a connection between the DAC chip and the ribbon due to the broken via, I've had to solder a bit of wire to the bottom of the board before the via's bring the signal to the top of the board. I've now got some little sockets that I can plug different caps into to do some cap rolling. :)
Dave, you definitely don't get any funny noises between tracks or when switching inputs? That would be the decider for me taking the muting relay out of circuit.
Better to use some thin wire IMO.Solder this to the board and take to the cap,then another wire from the other side of the cap to the phono.This way,you're only soldering to the board once,and it's easy to change caps too.See the pic I posted.
Ahh yes,I remember the posts on WAD Neal.I believe Greg amongst others has done the same.Quote:
Originally Posted by NRG
http://eshop.tirnaelectronics.co.uk/...40b090d9b781f9
This is the one I want right?
If that is right, then there you go everyone a useful link :)
Those will do the job Hamish.You might want to try a few different ones to see what you like.
Ta, yeah, one step at a time, I need to find out I it works in my hifi first :)
I'm really looking forward to comparing it to the majik ds-i!!
£2.12
Nope. I've tried optical and coax inputs and I've not heard any funny noises between tracks. That's using the soundcard on my PC as a digital transport. I'm not sure if the soundcard mutes it's output between tracks. So I guess it will depend on how your source handles muting. I think it's worth trying once you've decided which caps to use in the long term. :)Quote:
Originally Posted by MartinT
Hey Hamish..Quote:
Originally Posted by Hamish
thats the one Ive got from Jimmy at Tirna.
Its the Rubycon NA series...
think these are different from the ones (CA series?) that were fitted for the recent group buy Dave (hifidelityguy) organised for us?
I cant find anything online about the NA series, but Im assuming they are more modern than the CA..at least using the letter notation?
The ones from the link though are burning in nicely it has to be said...even at a couple of days.
big improvement over the opamp board/Grey Rubicon CE/AD826 opamps combo I had before.
Its just a lot more high end sounding...detail is sublime, bass through the floor (Stan got it right with kick drum hitting you in the back)...more of everything.
As others have reported, the increased dnamics are astonishing and to me best sum up the improvements..its as though there less to "get in the way" of the original sound.
To me its a bigger jumpo than fitting the Mutara regulators and the Elna Slimic IIs...
even a cack handed scotsman like me with no electronic skills done the job in 3 minutes..the opamp board just "pops" off.
I'm looking forward to your comparison between the Caiman and the Linn... :)
Next up, linear PSU from Maplins for me...big thanks to Jim(Trailer) for the 7520 PSU to use for the Maplins supply!
Yeah, def should be interesting... The majik/dynamic is a different ball game to how the majik was without dynamik
It's reassuring that someone who calls them self a "cack handed scotsman" can do it :)
Has anyone tried the passive mod without the reg and capacitor changes? I'm wondering what the hierarchy is for the mods. Could it be regs 1st, caps 2nd, passive 3rd? Based on the assumption that the passive mod lets you hear more of what precedes it so the preceding sections need to be at their best?
I could ask the same re the 7520 as well but I expect the extra resolution of the Wolfson is an important factor.
You can start with any of the mods first. It's not a chicken and egg situation:).
Hi Stan, I'm aware that technically they can be done in any order but what I'm wondering is whether, say doing the passive mod on an otherwise unmodified 7520 might for instance show up noise from the standard regs. There are times when too much resolution downstream shows up upstream components. I'm thinking about synergy, rather than whether it technically works.Quote:
Originally Posted by StanleyB
Get Tirna to mod your 7520 to include the Wolfson Dac..its worth it.Quote:
Originally Posted by Clive
Yes, there's no doubt I'm doing that (I won't tackle SMD), I'm trying to work out whether to do the other mods, though I'd do those myself. I know I'll end up doing the lot....Quote:
Originally Posted by Gazjam
BTW, the reason I've not got around to any mods yet is that I've been focused on my 2 record decks and phono stages, I can only cope with optimising one type of source at a time. Oh yes, there's new preamp too...too many changes!
Clive,I've done the passive mod on my 7510 which had previously had part of mod21 done (just the caps) The dac is otherwise standard.The passive mod certainly made by far the largest subjective difference to my ears.I used some Mundorf 'lytics,but have some SCR Obbligato on order as I reckon a film cap will give a better result in this application.
Thanks Ali, that's very useful info. As my preamp has a 100k input impedance it seems I can go the film route too, even paper in oil though I expect film to work out better. I have various 0.47uF and 1uF caps.Quote:
Originally Posted by Ali Tait
DiyHiFiSupply have Obbligatos at 47uF
Am I right in thinking 0.47uF to 1uF would be ok for a preamp of 100k input impedance (actually 94.4k)?Quote:
Originally Posted by Ali Tait
I am looking to do the passive mod to this particular 7520. Is there likely to be any problem if I attach the caps to the via's (where the orange wires are already attached)?
I intend to use the variable output to attach the passive caps so that I can swap between the two.
The op-amp board is attached by the two orange wires and I wonder if adding the 47uf caps (or whatever value I chose) will affect the active operation?
Any ideas?
http://i73.photobucket.com/albums/i2...Beresford2.jpg
[QUOTE=Clive;138972]Am I right in thinking 0.47uF to 1uF would be ok for a preamp of 100k input impedance (actually 94.4k)?[/QUOT
Yes I think so Clive.Try it and see.Shouldn't do any harm anyway.
I've been doing the passive mod on my 7510 and I agree with Ali it's the biggest bang for buck modQuote:
Originally Posted by Clive
So far I've tried out 47uf : Silmic II's, Nichicon ES & FG & KZ, Fine Gold" MUSE, Black Gate FK's.
My fav's so far are the Black Gates which I'm still running on one 7510 and on the other I'm just plumbed in Claritycap SA Range 4.7uf jobbies and these are sounding really nice. I had them knocking around from one of my valve amp projects so I thought I'd give'em a go. They are soaking in so I'll have another listen tonight.
The outputs are strapped down with a 100K TAKMAN resistors and this feeding a Silk TVC, which a 12K load. So with the 4.7uf it'ss around 3hz cut off.
I've also replaced the 5V regulator with an LM317 as they lower noise but I really dunno if that's made any difference though. Need to swop back at some time.
Just take the plunge you won't regret it :) Have fun.
Cheers / Stevie
I would also say that the passive output mod has given me the biggest improvement overall. That's using very cheap caps as well, so the bang for buck value is huge. You could of course use very expensive caps which may work even better but it's not essential. I see what you're saying about the possible issue with upgrading downstream components first. The passive output does allow more detail through as well as improve the dynamics, so you will be letting more noise through if you don't upgrade the regs. However, I think the improvements outway this, especially if you're going to be upgrading the regs later anyway.Quote:
Originally Posted by Clive
Also, the Murata regs don't affect the sound signature as such, they just improve the signal to noise ratio. So seen as the passive output caps can affect the sound signature and can take quite a bit of running in, I'd personally do the passive mod first. That way the caps can be running in while you wait for the regs to arrive. :)
Any reason not to try Black Gate 220uF 6.3v non-polars aside from possible charge/discharge thumps on power on&down? I just happen to have a pair.
Based on what others have said, I think this will depend on your amp. The roll off frequency at that capacitance rating will be way below 1Hz, so your amp may go into protection if it thinks it's been given a DC input. This will be dependant on how your amp deals with that situation though. Some have very little protection. A good amp shouldn't allow DC through to the speakers though, so there shouldn't be a safety issue I wouldn't have thought. You'll just have to decide if it's a risk you're willing to take. :)Quote:
Originally Posted by Clive
Clive that's fine, I'm currently using 0.47uF into 100K and there is no loss of Bass...Quote:
Originally Posted by Clive
I would also say forget 'lytics and stick with film type caps they have a much more even response.
I've just taken delivery of some Mungdorf MKP 15uF film caps. Unfortunately I ordered the 33uF version but got sent the worng ones due to an error on the diyhi-fi.co.uk website. :rolleyes: So watch out for that one. I've emailed them about the issue. I might give the 15uF's a sneaky try seen as I don't have to solder them. That should give me an idea of what to expect after I get them exchanged. :eyebrows:
One further installation tip I've found, while I've been installing my Rubycon NA bipolars from Tirna Electronics. The picture says it all.
http://www.hifiwatcher.com/wp-conten.../capacitor.gif
By the way, the Rubycons are adding much needed weight to the sound - above and beyond the Black Gate FKs.
Andrew
Anyone?Quote:
Originally Posted by Puffin
Nice diagram. This is what I've found with the Rubycon CE (grey) caps, the bass weight is superb. Do we know what the difference is between the CE and NA ranges?Quote:
Originally Posted by AndrewR
Rubycons arrived from Tirna,, removed the op-amp board and inserted the 47uF caps into the PIN3A socket .
Sounds very promising already but I dont want to solder them in .
Just thinking of a way to secure them with some insulation tape so i can put the top lid back on and transport the dac without the worry of them falling out.
Anyone try this?
Got mine from tirna too ... Doesn't work to well as a pre to the power amp in a nad c326bbe... Sounded very noisey. Works into the aux in though... Although it is mailing the monitor audio rs8 speakers sound bright and boomy.... But I fear that is more likely the bright and boomy rs8's sounding more bright and boomy beacuse that's how they sound
... This is kit at work I'm playing with... Not my own... I thought I'd try it on stuff I didn't mind breaking first :)
I use some double-sided foam tabs on the relay chip. The caps stick nicely to them when folder over.
Hamish Got mine from tirna too ... Doesn't work to well as a pre to the power amp in a nad c326bbe... Sounded very noisey. Works into the aux in though... Although it is mailing the monitor audio rs8 speakers sound bright and boomy.... But I fear that is more likely the bright and boomy rs8's sounding more bright and boomy beacuse that's how they soundQuote:
Originally Posted by Puffin
Hamish. See above.
cheers buddy... il try it in my kit at home first... im not bothered about the kit here ... i just wanted to see if it worked ... and i hadn't broken anything...
with that in mind....if i have any issue at home, what question do i need to ask anthonytd to find out what is the perfect cap value? (do i mean value?... sorry i am trying to learn... its just a bit of a confusing load of nonsence) or will the 100uf one more likely work anyway?
wow, this wee tweak actually works!
can confirm a more open and "bigger" soundstage with better seperation.
Regarding the caps falling out, when I pulled one out to reverse the way it fitted in (as per the diagram) it took a wee bit of pull to get it out...I dont think I'd have any problem with them falling out when moving the dac out - and in fact I didn't when unscrewing the case and moving the Dac this morning.
Just dont wave it about your head and you should be fine ;)
Hamish. Any distortion would not be as a result of the value of the caps. It is normally a mis-match with the impedance of the pre-amp. This can be overcome by attaching the right value resistor between the signal input and Grd for each channel. See the resistors attached in this pic.Quote:
Originally Posted by Hamish
http://i73.photobucket.com/albums/i2...sex/Fog003.jpg
...but in doing so you place a resistance in parallel with the input impedance of the amp/preamp making the impedance lower...you need to 'fix' the amp/preamp not place shunt resistors in the DAC.
Good stuff Gary,look forward to hearing yours against the 7510 and the AN.Quote:
Originally Posted by Gazjam
Had about 5 hours running in at work... Got home had about 45mins here so far.
First impressions, mixed bag...compared to the majik, Sound stage has is sat back, imaging seems more blurred and has lost a lot of the majik ds-i's 3d ness... For want of a better description. The bass sounds stronger and stands out as having more texture.. In fact everything has a touch more texture than the ds-i! The caiman sound a little more musical, smoother and slightly less edgy than the ds-i... Not unimpressed by any stretch. I don't think either is better, just different, for me the ds-I has the edge at the moment although that is only for it's ability to put instruments in the room within the soundstage.. If the caiman did that too, it would win!... Any caps better at 3dness? Should I wait for these to burn in a bit more?
I will leave the caiman running whilst I sit an listen to music this evening and go back and forth to it periodically to see how it's doing.
If I'm expecting these caps to run in, how long should I expect to wait?
The new system is much better at picking out difference in dacs I think... I'm less disolutioned with them now :)
Fantastic tweak indeed ,would recommend it to any 7520 owner .
Have about 5 hrs burn in now but even instantly they made a much bigger difference than changing opamps ,
Have noticed that i need to turn up the volume a few notches more on my amp now but this is not a problem,
Wondering how much more of a difference id get if i upgraded to the wolfson chip too? mmmmmm.....
Actually il retract that bit about the dsi having the edge... I'm being more seduced my the musicality ... And with my Adams already kicking me into the sofa with a bit of bass the caiman seems to have adde to that!
I do wish for the 3dness and focus of the majik soundstage though....
I forgot to mention, it much better than the active output thing though... The majik ds-I had a def edge on that.
It silly this ... I seem to be having a nver ending competion between these 2 dacs...
Next stage is send the majik to audiocom
Give the caps a chance Hamish,maybe leave something on repeat overnight into the dac.
Yeah, that's a done deal matey... I'm giving my self the afternoon off tomorrow ... Il cone back to it then!
Some caps can take ages I've found.When I first fitted the SCR teflons to my amp,I reckon they took weeks to settle properly.
... I shall stick with these for a few weeks then...