awpagan said:very nice work Ray
I've been using the tent XO module with a his psu (psu home made). passive filter(4,7mH version) and the bc550c buffer(filter and buffer on home made pcb)
Was thinking about using HDAM circuit but pain in a** to remove pcb to vary anything. just this weekend started doing extra power supplies. didn't want to disrupt it, just sounds very good
Much difference between fet and transistor?
allan
Hi Allan,
Thanks. I'm using the Tent XO too, on my former-CD67-PCB. I also made a small PCB for that, including the PSU section. Works very well.
I haven't heard the difference yet between the transistor and the FET version, because the FET-player isn't fully tweaked yet. I'm hoping to receive the parts this week. Then i'm going to see which one is better and compared that with the tubestage.
Regards,
Ray.
Attachments
Dr.Gone said:Lucky throw that was! I don't think it would happen to me
LT340's? What are those?
Let us know what you find, i'm curious about what the impact of that cap is, especially with LM6172's.
I'm such a happy tweaker! Now I can listen to all my cd's all over again
Thanks everybody
regards,
Jacco
Tough job, but someone has to do it! Keep on smilin'....
Regards,
Ray.
Morning chaps,
I got itchy fingers yesterday and decided to de-captivate my thick power lead and install an IEC socket. It's a tough job with a pants drill and cheapie jigsaw, but it worked. Just a convenience upgrade, so I was now in need of a real sound upgrade...
...so I then added some star earthing. I used a piece of veroboard about 4 tracks wide and pasted it with oodles of solder. I added I think 8 runs of wire of equal length from various points on the pcbs. The one from the mech pcb I insert into a screw terminal so the whole thing can come apart easily.
The wire is individual parts of Kimber 4VS that I had knocking around - multistranded and reasonably thick. I've not grounded it to the house earth yet as it was getting late, and I've not added an IEC plug to my monster CAT5 lead so things aren't 'optimal' yet, but...
The sound has improved on a listening session I enjoyed before work. It seems to have more control and less mess, with hard solid bass. The imaging is a little better too.
I'd say adding some star earthing is well worth it but due to having a mess of wires top and bottom it's one to leave till later.
Regards,
Simon
ps- Diana Krall showed the improvements (The Girl in the Other Room). Eleanor McEvoy also sounded unfamiliarly good since the last few mods - earthing, new RCA sockets, coax on HF line. On her album Early Hours the background seemed very quiet and everything was precise but bold. The way real music sounds...
I got itchy fingers yesterday and decided to de-captivate my thick power lead and install an IEC socket. It's a tough job with a pants drill and cheapie jigsaw, but it worked. Just a convenience upgrade, so I was now in need of a real sound upgrade...
...so I then added some star earthing. I used a piece of veroboard about 4 tracks wide and pasted it with oodles of solder. I added I think 8 runs of wire of equal length from various points on the pcbs. The one from the mech pcb I insert into a screw terminal so the whole thing can come apart easily.
The wire is individual parts of Kimber 4VS that I had knocking around - multistranded and reasonably thick. I've not grounded it to the house earth yet as it was getting late, and I've not added an IEC plug to my monster CAT5 lead so things aren't 'optimal' yet, but...
The sound has improved on a listening session I enjoyed before work. It seems to have more control and less mess, with hard solid bass. The imaging is a little better too.
I'd say adding some star earthing is well worth it but due to having a mess of wires top and bottom it's one to leave till later.
Regards,
Simon
ps- Diana Krall showed the improvements (The Girl in the Other Room). Eleanor McEvoy also sounded unfamiliarly good since the last few mods - earthing, new RCA sockets, coax on HF line. On her album Early Hours the background seemed very quiet and everything was precise but bold. The way real music sounds...
Sounds good Luke, but I'm not qualified to say.. I simply followed Brent's suggestions for star grounding.
Ideally we want as low resistance grounds as possible with, I believe, equal resistance from each circuit to the star point. This should then be connected to your house earth, which must be very good (low resistance) too. Some people advise connecting the unit's earth to the house earth via a low value resistor, in order to prevent a groundloop - somebody correct me if I'm wrong here please. Also, the casework can be directly connected to the house earth.
Among the bits I connected were the mech pcb, the 12v star near the regs, the 5v star, U198 and U197 (DAC), decoder (between pins 22 and 23) and near U201 (around RCA sockets). I'm going to connect this star point to the ground on my new power socket. I will of course connect the ground from my future regulators/psus here too.
Simon
Ideally we want as low resistance grounds as possible with, I believe, equal resistance from each circuit to the star point. This should then be connected to your house earth, which must be very good (low resistance) too. Some people advise connecting the unit's earth to the house earth via a low value resistor, in order to prevent a groundloop - somebody correct me if I'm wrong here please. Also, the casework can be directly connected to the house earth.
Among the bits I connected were the mech pcb, the 12v star near the regs, the 5v star, U198 and U197 (DAC), decoder (between pins 22 and 23) and near U201 (around RCA sockets). I'm going to connect this star point to the ground on my new power socket. I will of course connect the ground from my future regulators/psus here too.
Simon
Luke said:
soldering every chips earth would be lot of link wires not practical IMHO
the top layer is a ground plane for all earths, digital analogue and psu.
look at the earth links already on the pcb
there are solder links from bottom to top in various places
a couple for digital some analogue and one main power
I've remove links to top plane and connected wire strait back to star grd
also top plane earth wire taken between main psu caps and also from processor point back to star
star earth is digital earths together then analogue earths together
whether this has improved cannot say
did with iec socket
Star earth is bolted to chassis with iec earth
allan
ps ray took his star from rca earth
done some mods again tonight.
* installed a iec mains inlet (with emi filtering, i'm not sure if that has any benfit?)
* added a 4n7 capacitor across the mains in jh03,
* applied in total 8 100nF decoupling capacitors to elco's around opamps and power supply.
After a first listening session I was quite surprised that these mods really made some difference. The sounds is calmer and more relaxed and there is more space for instruments.
Tomorrow I will install my new bought tent xo.
* installed a iec mains inlet (with emi filtering, i'm not sure if that has any benfit?)
* added a 4n7 capacitor across the mains in jh03,
* applied in total 8 100nF decoupling capacitors to elco's around opamps and power supply.
After a first listening session I was quite surprised that these mods really made some difference. The sounds is calmer and more relaxed and there is more space for instruments.
Tomorrow I will install my new bought tent xo.
6h5c said:LT340's? What are those?
[/B]
Wait a minute! You are not making fun of my error are you?
Oh well... that's the last time i write a post recalling those silly codes from the top of my head.
I hope I will have time this week to do a serious test of the lm6172, but first I need time to get a bit of grasp of the sound of the 827's in their new environment.
Regards,
Jacco
Serious testing...
Due to many modifications in a short time I think it's hard to recognize the effects of a single step. Do you have a system for comparison?
From time to time I notice some difference in the reproduction, what could well be the result of a mod in the past, like changing supply caps.
Due to many modifications in a short time I think it's hard to recognize the effects of a single step. Do you have a system for comparison?
From time to time I notice some difference in the reproduction, what could well be the result of a mod in the past, like changing supply caps.
Re: Serious testing...
I use the same cd for every listening test, this way I know exactly what gains (or losses) I have. I know the cd inside out. I use Diana Krall - The girl next door. I find this has sweet vocals and excellent varied bass and treble notes. Then ill test other cds with fast bass etc.
I can pick out certain notes or noises and always remember them, maybe i'm good at this with having been an audio engineer
Brent
disco said:
I use the same cd for every listening test, this way I know exactly what gains (or losses) I have. I know the cd inside out. I use Diana Krall - The girl next door. I find this has sweet vocals and excellent varied bass and treble notes. Then ill test other cds with fast bass etc.
I can pick out certain notes or noises and always remember them, maybe i'm good at this with having been an audio engineer
Brent
Re: Serious testing...
Some do one mod at a time or have a few players
for sound comparisons, use your favourite disc's or tracks.
use the same equipment and some mods will have a big difference,
others more suttle.
allan
ps probably why the kas50 clone has not got any further.
pps nora's disc is playing again
disco said:
Some do one mod at a time or have a few players
for sound comparisons, use your favourite disc's or tracks.
use the same equipment and some mods will have a big difference,
others more suttle.
allan
ps probably why the kas50 clone has not got any further.
pps nora's disc is playing again
Re: Re: Serious testing...
brent
for bass, Herbie Hancock did an album and the double bass solo on it was incredable, perfect for testing lows.
I think it was a record (vynal), still trying to find it.
still looking.
allan
rowemeister said:
I use the same cd for every listening test, this way I know exactly what gains (or losses) I have. I know the cd inside out. I use Diana Krall - The girl next door. I find this has sweet vocals and excellent varied bass and treble notes. Then ill test other cds with fast bass etc.
I can pick out certain notes or noises and always remember them, maybe i'm good at this with having been an audio engineer
Brent
brent
for bass, Herbie Hancock did an album and the double bass solo on it was incredable, perfect for testing lows.
I think it was a record (vynal), still trying to find it.
still looking.
allan
Re: Bestplace to pull power for clock card
Hi Dave,
What voltage(s) does your clock need? At C803/804 you'll find close to +/-24V depending on their size, after Q801/802 it's +/-12V. I wouldn't recommend tapping it from there, since that is the analog supply, but it will do no harm, it's temporary. If the clock needs only a single supply you can tap it from C813, it's around 12V there.
Regards,
Ray.
Gooch said:
Hi Dave,
What voltage(s) does your clock need? At C803/804 you'll find close to +/-24V depending on their size, after Q801/802 it's +/-12V. I wouldn't recommend tapping it from there, since that is the analog supply, but it will do no harm, it's temporary. If the clock needs only a single supply you can tap it from C813, it's around 12V there.
Regards,
Ray.
