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Post by Deleted on Nov 6, 2012 9:52:46 GMT
About the XO's power: From the schematic (here: amanero.com/CPLD_D.pdf) it can be seen that: 1. the XO's have an enable pin. When disabled the oscillator is simply in a low power state without generating an output. 2. Output from both XO's goes to 2 different global clock net pins of the CPLD. 3. feeding both XO's at a single point is not possible, since at the other side of the inductors it connects to VCC_3.3V, which in turn ties to VCC_3.3V_USB, which powers all digital stuff on the PCB. It should however make no difference if both XO's are powered from a single source (with inductors L2 and L3 removed off coarse). Cheers, Marc Hi Marc thanks for the explanation which helps throw light on the subject. take care
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pagan
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Post by pagan on Nov 6, 2012 11:51:47 GMT
You right Gommer
Separate psu's for the clocks may not gain anything.
Their is another reg for 1.8volt thought, maybe for the processor itself. isolating that on it's own psu may help. Since the clock that goes to the dac, goes through the processor, a clean psu for the it may help with phase noise.....
Thinking out loud here, need to study it a bit more.
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Post by Deleted on Nov 6, 2012 12:14:36 GMT
Hi All So a little further down the rabbit hole today by snipping out that 5 legged 3V3 spider reg and powering straight from a dedicated JLH supply. I ended up going straight to the side cutters because it’s just a little crowded around the reg but I still have enough leg on it to solder back if I need to (which I don’t) Mmmmmmmmmm Interesting After a quick listen IMHO to my ears in Alex’s system The first thing that I noticed was that Mr Bass had come back out to play. Yup obvious improvement on that front. Also just a smidge more detail and added smoothness to the sound but not hugely so. A nice side effect is that I lose the PSU injector box which will go back to its ripping and playback duties. Also I’m now running it on 0.6M of Formula 2 (Vbus connected)so a nice reduction on that front also and yes IMHO size really does matter with USB cables. Shorter the better IMHO So a little more compact and self-contained with a nice increase in bass weight. That little 3V3 is a well spec’d reg but maybe in this case specifications don’t tell the whole story. I really have not much idea why the few mods that I’ve done should have changed the sound but IMHO they have for the better. Maybe others will have some ideas on that. IMHO it’s now sounding like a much more expensive piece of kit and way beyond it’s humble price. Good work Domenico Rats I knew that I should not have got the iron out. Take care
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Post by gommer on Nov 6, 2012 12:32:58 GMT
Ah, the 1.8V supply. That is the core voltage for the CPLD only. I/O power supply for CPLD is 3.3V That's correct if you replace processor with CPLD. The processor handles USB conversion only, CPLD does the timing. But i wonder, has anyone seen this: hifiduino.wordpress.com/2012/11/04/amanero-bit-clock-re-clocking-results/That would make more sense and might make all other power supply mods obsolete, except for the XO's power supply. The idea is to cleanly reclock the master clock, right before input to DAC and leave all other signals as is (clean enough in order to be interpreted correctly). Makes sense? Anyone with a hot iron ready, willing to try this? Reclocking with any 74xxx flip-flop would do as a first test. In case volunteers are really courageous, it would also make sense to try and reclock data and wordsync also. Or a simpler version: buffer data and wordsync. The reclocker should in all scenarios be cleanly powered of coarse. Cheers, Marc
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Post by Deleted on Nov 6, 2012 17:58:58 GMT
Shaun, Just that 1.8v reg left then I've yet to attack mine, too much "stuff" going on at the mo, so all talk and no action
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Post by Deleted on Nov 7, 2012 10:49:54 GMT
Shaun, Just that 1.8v reg left then I've yet to attack mine, too much "stuff" going on at the mo, so all talk and no action Hi Chris snipping out that 3V3 really took no time at all the whole mod was done and dusted in around 1/2 an hour. snip snip SNIP style then just solder in a 2 pin header to the 3V3 and 0V and it's done. I'm going to leave that 1V8 in for now. but now i have the board opened up to PSU experimentation at a later date. take care
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Post by Deleted on Nov 7, 2012 13:07:13 GMT
Had myself a more serious session with Jplay today and the Amanero is sounding very good indeed. and on further listening I'm pretty happy with the SQ. in no way meant as a criticism but i found the Amanero in standard form a little dry and laking is bass weight. having thought about the best description for the sound i think that ''just a little hollow'' fits. the music is all there but lacking in a little substance. using Alex's Power injector sorted that to some extend and the XO mod added a little refinement at the cost of a bass weight. snipping out the 3V3 seemed to bring the sound back into balance with more detail and clarity and it's now sounding just great. bass goes down low when required and really loved to party. it was deep and tuneful with OTT-Hallucinogen Remixes with plenty of detail. had a listen to Alison Kraus-Paper Airplane which sounded so real (real voices and real instruments) with a cavernous sound stage where as before the mods it sounded just a little flat, thin and papery. as i say no criticism meant and for the cost the Amanero it's waaaaay beyond reproach. but with a few not so hard tweaks it really blossoms. my wife noticed the difference pretty much straight of the bat without knowing what or if I'd changed anything. the JLH seem to be doing a great job with the Amanero and as for Alex's amps well they are so transparent. they show source inadequacies pretty quickly and take no prisoners in that respect. but given a decent source they sing like no other I've heard tube or SS. a class A act. so right now I'm happy enough to leave well alone (for a change ) that little Amanero board is A RIGHT RESULT well done Domenico so the usual apples IMHO, IN MY SYSTEM, TO MY EARS take care
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Post by Deleted on Nov 8, 2012 9:29:56 GMT
With the switching XOs in mind and no obvious place on the board to supply both from a single dedicated 3.3v supply. How about a simple twin +ve lead affair from said supply, one lead per XO. In the case of a cricket I was thinking to stack the chips in case of any small draw from the off state XO.
Waddya fink folks?
Sent from my HTC One S using proboards
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Post by Deleted on Nov 8, 2012 14:39:53 GMT
Hi Chris ''How about a simple twin +ve lead affair from said supply, one lead per XO'' yup that's how i ended up powering my XO's one JLH supply and two +ve leads. take care
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Post by Deleted on Nov 9, 2012 9:32:40 GMT
Hi Shaun,
I've just popped my twin +ve leads on for XOs and will be testing a little later. How in blazes did you get at the LDO to remove it! My snips are too chunky to access all the legs and I'm not keen to go the braid method with that high melt solder. Any useful pointers are very welcome! Cheers, Chris
Sent from my HTC One S using proboards
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Post by gommer on Nov 9, 2012 10:07:47 GMT
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Post by Deleted on Nov 9, 2012 10:59:23 GMT
Hi Shaun, I've just popped my twin +ve leads on for XOs and will be testing a little later. How in blazes did you get at the LDO to remove it! My snips are too chunky to access all the legs and I'm not keen to go the braid method with that high melt solder. Any useful pointers are very welcome! Cheers, Chris Sent from my HTC One S using proboards Hi Chris Marc is right those hot air rework stations can be useful. I have one myself but decided against using it due to the close proximity of other components to the reg . I had visions of a fast moving game of blow football with components going everywhere. I also decided against trying to de-solder for the High melt solder reason that you’ve mentioned. I was much more interested in preventing damage to the board. My side cutters are the flat blade type made by Rolson and sold by Maplins. I find them better for fine work and made snipping the reg out a piece of cake. If you have the rounded type ones then it may make things a little more tricky. www.maplin.co.uk/mini-wire-cutters-32199I get through quite a lot of those side cutters and replace them regularly to ensure nice sharp blades. it would have been nice to boast about my surgeons hands and skill under pressure. but it's not so ;D So Chris flat bladed side cutters are the thing with a nice fine point on them. A five min job Even ended up with enough leg left on the thing to solder back if required. You have the more difficult part done already take care
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Post by Deleted on Nov 9, 2012 11:10:17 GMT
Hi Chris Only you can decide if further potential small gains over what you have already achieved, outweigh the risk of a damaged unit. Kind Regards Alex
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Post by Deleted on Nov 9, 2012 11:20:09 GMT
I know nowt about these things but, having looked at Marc's link, it occurred to me that a hot air blower similar to those many of us must have for heat shrink sleeve purposes could perhaps serve the same purposes, or perhaps even the wife's hair drier . Perhaps one of those 'Helping Hands' thingys might be useful in holding the hot air source? I'll now get behind the sofa . Dave.
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Post by Deleted on Nov 9, 2012 11:50:34 GMT
Hi Chris Only you can decide if further potential small gains over what you have already achieved, outweigh the risk of a damaged unit. Kind Regards Alex Hi Alex good point and something i thought long and hard about before curiosity got the better of me. if i was asked if i thought it was worth the little effort involved then I'd say yes as i believe that the small gains add up. if i was asked for a guarantee that Chris would hear the same things as i have then of course I'd say no such undertaking could be given. However there are other benefits other than just pure SQ 1)simplification of the system 2)shorter USB cables can be used so i made my choice based on SQ and the above points others may have different priorities and will decide accordingly. i do try to be careful when giving subjective thoughts. i always say ''IMHO to my ears in my system'' everybody needs to think carefully before starting such things so fair point. Hi Dave good thinking but the rework stations have a number of features 1) heat setting control 2) air flow control 3) specialized nozzles for each task no need to hide you made some good points worth discussing that's how i learn take care
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Post by gommer on Nov 9, 2012 12:15:46 GMT
I actually did some tests WRT this subject some months ago.
First of all, adhesion makes sure other components stay put, provided the airflow is not set to maximum. You can also control the temperature very accurately with distance, i've learned.
My goal at the time was to see if the reflow process could be mimicked with a hot air nozzle. I used a thermocouple and a rework station at work with various temperatures, air flow speeds and distances. It seemed that if you put the temp at something like 380 to 400°C, with modest airflow (40-50%), you can vary temperature from 200°C at component level (distance of 10cm), up to 320°C at component level (distance 1-2 cm). That way you can pre-heat without going liquid and make the solder liquid in a short time only, very localized. Some nearby passives might have liquid solder joints in the process, but they won't go floating, for sure.
Just some off topic rambling that might be useful.
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Post by Deleted on Nov 9, 2012 12:46:52 GMT
I actually did some tests WRT this subject some months ago. First of all, adhesion makes sure other components stay put, provided the airflow is not set to maximum. You can also control the temperature very accurately with distance, i've learned. My goal at the time was to see if the reflow process could be mimicked with a hot air nozzle. I used a thermocouple and a rework station at work with various temperatures, air flow speeds and distances. It seemed that if you put the temp at something like 380 to 400°C, with modest airflow (40-50%), you can vary temperature from 200°C at component level (distance of 10cm), up to 320°C at component level (distance 1-2 cm). That way you can pre-heat without going liquid and make the solder liquid in a short time only, very localized. Some nearby passives might have liquid solder joints in the process, but they won't go floating, for sure. Just some off topic rambling that might be useful. Hi Marc not at all rambling and very useful information i guess that some of my apprehension is purely down to my age and lack of experience with rework stations. i also worry about my own tendency to be a little ham fisted with such small components. those observations have encouraged me to have another look at things. thanks for the tips take care
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Post by Deleted on Nov 9, 2012 13:18:28 GMT
I'm currently listening to my Amanero with the XOs fed their 3.3v via a single JLH/CKT (with stacked chips just in case). I wouldn't call the change overly subtle, very much like removing tracing paper from an outline and viewing the image directly. I'll see if I can cop hold of some flat blade side cutters today so I can attack that LDO next. Attachments:
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Post by Deleted on Nov 9, 2012 14:46:34 GMT
I'm currently listening to my Amanero with the XOs fed their 3.3v via a single JLH/CKT (with stacked chips just in case). I wouldn't call the change overly subtle, very much like removing tracing paper from an outline and viewing the image directly. I'll see if I can cop hold of some flat blade side cutters today so I can attack that LDO next. Hi Chris Good job on handling those fiddly pad connections. yup i noticed a difference but TBH I'm pretty reluctant to claim ''huge improvements'' unless I've had a decent amount of time to listen. yes as you say clarity did improve nicely and as i said the sound was slightly less ''hollow''. finding that change in SQ surprised me a little and in turn made me wonder about the influence that the 3V3 reg was having on the sound. looks like you have your board Async can you confirm that just so i have a better idea of where you are comming from. glad you like it take care
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Post by Deleted on Nov 9, 2012 16:06:58 GMT
Shaun,
Yes, ASYNC at the moment. I'll try SYNC again when I have the last 3.3v sorted out.
Cheers,
Chris
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Post by Deleted on Nov 9, 2012 16:21:50 GMT
Shaun, Yes, ASYNC at the moment. I'll try SYNC again when I have the last 3.3v sorted out. Cheers, Chris Hi Chris thanks for the update it would be interesting to have your thoughts on the sound with SYNC now that the clocks had a dedicated PSU. I've not tried it myself but it may sort some of the traits that you reported when you tried it before. interesting to find out. take care
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Post by Deleted on Nov 9, 2012 17:59:38 GMT
Wow! great job Chris! Most probably next week I'll have this f*ck'n monster powering my Amanero with onboard 3.3V reg removed: The cap is a 10,000uF monster! and what about the 400g heat sink... holy cr*p! (the reg is calculated for 300mA) Hifiduino has posted some firther tweaks he has done to his Amanero board and looks like this time he has nailed the reclocking: hifiduino.wordpress.com/2012/11/08/more-tweaks-on-amanero/
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Post by Deleted on Nov 9, 2012 18:34:38 GMT
Hi Javier you bad man you ;D posting a picture of the Darth Vader of regs just hard to resist that's my next move so looking forward to comparing notes with you on that. if Mr M still has your board then you could ask him nicely to remove those 2 chokes powering the XO and solder you some long wires in there. the clocks do seem to benefit from a separate supply. you could reduce the current a little on the Salas if you did it as the above so it would run a little cooler. I'm going to set my Salas for 250ma initially as i now don't have powering the clocks to worry about. I'll be etching some of Alex's nice crickets next week sometime if you would like a board to try let me know. welcome to the dark side take care
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Post by Deleted on Nov 9, 2012 19:02:36 GMT
The force is strong in you Shaun, do not resist, join the dark side.. ;D I asked Mr. M for 300mA so it will have enough juice to power a "future" DSD DAC (maybe from "A"?), or at least its digital section. Not sure about the XOs modding part yet, "A" may also have a surprise for us in this area, I'll give him some time before modding.
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Post by Deleted on Nov 9, 2012 19:12:44 GMT
Crikey! Are you "terraforming" on another planet You'll be good friends with Endesa (or Iberdrola) "Hmmmm, maybe the dark side not is this, much money from this young sith draw we will"
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