pzogal said:
Hi Pawel,
I tried some antenna-coax IC's, but wasn't impressed. Maybe it's the quality of the materials used that is not suited for audio. If you use a high-end silver type MIL-spec coax the results will probably be better, but most standard coax is rubbish.
The difference with solid UTP is that you don't have the stranded wires or braided screen. Solid cores give better results in my experience, especially if they are isolated from each other (a number of good cable manufacturers use this technique, like Monster, Supra and Nordost). UTP often has polypropylene or polyolefin isolation, which is better than PVC. So a lot of positive properties are already present with UTP cable, which makes it suitable for audio
. And it's cheap! 
. But make sure you use solid UTP with non-PVC isolation. The outer jacket can be PVC.I also have very good experience with Nordost, their entry-level Black Knight is a very nice interconnect.
I'll get back to you on the shunt regs.
Ray
Polyethylene is a nice-sounding insulation too. Something like a Nordost Black Knight can be smoked by some twisted enamelled copper and good plugs (Bullets, Vampire pure OFC etc.) Wires made like that (I used some thin DCT stuff I found on Ebay) easily surpass £100 commercial efforts. I recently sold an £88/0.5m interconnect because it was so outclassed in terms of refinement and tone etc by this wire (and more so by my copper foil one).
Simon
Simon
Thanks for all the sugestions, for the ICs, I'll solder some CAT7 I still have left after making speaker cables. Those are pretty neat:
- Cu single wire
- each pair is shielded
- thick (for speakers) - 23AWG
- PE isolation
Btw, I was able to hear the difference between 2x3m:
a) 3x braided CAT7
b) some cheap Oehlbach 2.5mm2 OFC
c) 3x braided CAT5 (thinner and of lower quality than a)
d) some no name 6mm2 allegedly OFC
and it was even on my sony 5.1 receiver not modded. The order is of course from best to worst. With d) there was clear high-end degradation (high capacitance ?). a) has best bass and hi extension. c) had bad bass.
So, for me the next steps will be CAT7 IC + I'll try different regs and see what happens Ok I can imagine disabling opamps could help, too...
Greetings,
Pawel
P.S. Regarding test music, my test CDs are
Ray Cooder (Mambo Sinuendo, Talking Timbuktu), Peter Gabriel (Up,Us,So), DM Violator, Patricia Barber, Pink Floyd, etc. any more suggestions ??
- Cu single wire
- each pair is shielded
- thick (for speakers) - 23AWG
- PE isolation
Btw, I was able to hear the difference between 2x3m:
a) 3x braided CAT7
b) some cheap Oehlbach 2.5mm2 OFC
c) 3x braided CAT5 (thinner and of lower quality than a)
d) some no name 6mm2 allegedly OFC
and it was even on my sony 5.1 receiver not modded. The order is of course from best to worst. With d) there was clear high-end degradation (high capacitance ?). a) has best bass and hi extension. c) had bad bass.
So, for me the next steps will be CAT7 IC + I'll try different regs and see what happens
Ok I can imagine disabling opamps could help, too...Greetings,
Pawel
P.S. Regarding test music, my test CDs are
Ray Cooder (Mambo Sinuendo, Talking Timbuktu), Peter Gabriel (Up,Us,So), DM Violator, Patricia Barber, Pink Floyd, etc. any more suggestions ??
6h5c said:
No, so I could be wrong. I heard that interconnect a while ago in a hi-fi shop (I think!!) as well as several others. When I worked there I did like Chord's products, but the good ones were £200 and £500, which is a lot of money for a wire.
DCT (cryo treated) enamelled copper on pure copper RCAs easily surpasses Kimber PBJ and the more expensive Russ Andrews Crystal-Cu in A-B testing. It might be largely due to those using Kimber Ultraplate phonos, which are nothing special (pure nickel or something).
Anyway, none of these wires are that interesting... braided very pure silver in teflon or copper (or even silver) foil is where it starts to get really interesting (full detail, bass and natural space).
Simon
pzogal said:
Diana Krall - The Girl in the Other Room
Jazz at the Pawn Shop XRCD
Eric Clapton - Unplugged
Linn - any!
On the Krall disc track 12 is a wonderful detail barometer - the number of static pops shows how much detail you have. Don't worry if you can't hear any - just keep upgrading and they'll come!
Good wiring, a clear amp, and the servo and DAC clocks & regs are needed to hear all those little details very clearly.
My CD650 has just started to play those pops, which is nice!
Simon
My favourite CD at the moment is Carol Kidd - Debut (on Linn Records). "I like to recognise the tune" is great for showing dynamics, drums, cymbals, overall naturalness and the female vocal quality. I often listen for how pronounced the treble is and how deep the bass sounds. You have to like soft female jazz vocals though!
ok, I have to give up, DOS is does its job right!!
had just listening session with Patricia Barber - Modern Cool
with DOS there was little more resolution in background instrument, bass was slightly different and there was more timbre in the voice, but as I wrote before, the difference is small. I connected the dos via twisted pair this time.
but I think I know where is the prob, it's psu. I hooked scope and observed Vin / Vout of the LM regs. Input ripple was about 100mV amplitude and Vout was 10mV which is high! even when looking at the datasheet there should be at least 60dB ripple rejection, not 20!
I am stucked, the regs have 100uF at the output, 1uF (tantalum) (+ loads of uF on the main board) at the input and 22uF (pana fc) at the adjust pin. R1 is 120R and there are 2 protection diodes (1N4007).
The trace looks a bit like triangle with f = 150-200Hz and what's more strange , there is the same trace when I touch gnd with the probe (when probe + scope gnd is shorted there is a flat line), any ideas on that ?
thanks in advance!
Pawel
had just listening session with Patricia Barber - Modern Cool
with DOS there was little more resolution in background instrument, bass was slightly different and there was more timbre in the voice, but as I wrote before, the difference is small. I connected the dos via twisted pair this time.
but I think I know where is the prob, it's psu. I hooked scope and observed Vin / Vout of the LM regs. Input ripple was about 100mV amplitude and Vout was 10mV which is high! even when looking at the datasheet there should be at least 60dB ripple rejection, not 20!
I am stucked, the regs have 100uF at the output, 1uF (tantalum) (+ loads of uF on the main board) at the input and 22uF (pana fc) at the adjust pin. R1 is 120R and there are 2 protection diodes (1N4007).The trace looks a bit like triangle with f = 150-200Hz and what's more strange , there is the same trace when I touch gnd with the probe (when probe + scope gnd is shorted there is a flat line), any ideas on that ?
thanks in advance!
Pawel
a quick scope follow up:
pre-reg pattern is triangle ca. 200 Hz , amplitude 60mV
post reg is hf-garbage around 10mV
it's a bit less than 10mV with DAC disconnected
inside there is a ripple around 5mV
the values are just order of magnitude due to scope reliability/readability
anyway with scope connected to 2 gnd points it picks up hf noise with amplitude around 10mV, I suppose this can be due to ground loops
and on the dos output, there is also hf garbage, a tick more than in the opamp stage...
so to get things right, shunt is probably not enough, an additional transformer + bridge + caps has to be fit in, too...
pre-reg pattern is triangle ca. 200 Hz , amplitude 60mV
post reg is hf-garbage around 10mV
it's a bit less than 10mV with DAC disconnected
inside there is a ripple around 5mV
the values are just order of magnitude due to scope reliability/readability
anyway with scope connected to 2 gnd points it picks up hf noise with amplitude around 10mV, I suppose this can be due to ground loops
and on the dos output, there is also hf garbage, a tick more than in the opamp stage...
so to get things right, shunt is probably not enough, an additional transformer + bridge + caps has to be fit in, too...
pzogal said:
A slight ripple at the input of the regs is normal, as you take the raw supply from the rectifier caps. The stuff you measure at the output is not from the regulators, it looks like your scope is the main problem. If you connect both the probe GND and tip to the same point, the line should be flat. Most probes are not well screened and pick up the HF garbage radiated by all the clocked IC's in the player. Also, the loop of the groundwire acts as a pick-up coil. Try to wrap the groundwire closely around the probe and pick a GND close to the point where you measure. Or measure the DOS outside the player, connected to a bench supply.
Regards,
Ray
Hello again newbie is back with more silly questions
I'm still at the practice on the old sky box stage and itchin to try some mods!!!
I seem to have mucho problemo removing old solder
I have braid, wont remove jack**** just gets too hot on lil pinkies, and pump, works sometimes but mostly not
I think im just too slow on the pump the solder sets in millisecs!!
i melt remove tip and almost instantly i see it go solid.
Am i just not fast enough or not heating long enough? I thought the wick would kinda draw the solder away it seems to do nothing except get hot!
Must admit i bought the cheapest items from maplin and a workman should never blame his tools but this is getting me down
When resoldering the joint has good shape but colour of steel not shiney, im cleaning the tip and tinning all looks well until i remove tip and a grey mist appears.. Too hot?
Maybe i just need practice
I'm still at the practice on the old sky box stage and itchin to try some mods!!!
I seem to have mucho problemo removing old solder
I have braid, wont remove jack**** just gets too hot on lil pinkies, and pump, works sometimes but mostly not
I think im just too slow on the pump the solder sets in millisecs!!
i melt remove tip and almost instantly i see it go solid.
Am i just not fast enough or not heating long enough? I thought the wick would kinda draw the solder away it seems to do nothing except get hot!
Must admit i bought the cheapest items from maplin and a workman should never blame his tools but this is getting me down
When resoldering the joint has good shape but colour of steel not shiney, im cleaning the tip and tinning all looks well until i remove tip and a grey mist appears.. Too hot?
Maybe i just need practice
Don't move the iron away whilst operating the desoldering pump. Press the pump right up to the joint with the iron tip still there. You may start melting the plastic tip, but it'll last ages all the same.
The best desolder pumps have silicone tips which withstand the heat of the iron.
The only braid I found to work was from Mappo's, but they don't seem to sell that brand any longer. It didn't require any cleaning up either but I've completely forgotten what it was called!
Cheers, Lee.
The best desolder pumps have silicone tips which withstand the heat of the iron.
The only braid I found to work was from Mappo's, but they don't seem to sell that brand any longer. It didn't require any cleaning up either but I've completely forgotten what it was called!
Cheers, Lee.