answer to MEPER #1378
Hello MEPER,
so you've got the 'red limited special edition - NORWOODs' with that little
extra warm sound.
I thought about it for a long time, that the colour of the soldermask will influence
the sound of an amp!
So I have to search for NORWOOD-boards in class A- heat- red?
Greets
Dirk
Hello MEPER,
so you've got the 'red limited special edition - NORWOODs' with that little
extra warm sound.
I thought about it for a long time, that the colour of the soldermask will influence
the sound of an amp!
So I have to search for NORWOOD-boards in class A- heat- red?
Greets
Dirk
Yes, the only reason I buy expensive ($50 - $100 range) cables is that I like good connectors (also a power cord cable with screen can be good to suppress these nasty current spikes which can radiate noise if cable too close to other cables). Some of them also just looks good…….it also depends where "expensive" starts......Nordost Valhalla probably starts a bit higher than $100?
I am using this power cord on my M2x. It is 2 meters long and rated for 15 amperes (internal wires are AWG-14). The cord is fully shielded, and costs USD 12.28 at Mouser.com:
part number 686-17604
here is the data sheet (.pdf) with technical data and mechanical drawings
part number 686-17604
here is the data sheet (.pdf) with technical data and mechanical drawings
Should be a very interesting event. I love the marketing pitch for their Signature Series interconnects:
- SOLID PERFECT-SURFACE SILVER (PSS) CONDUCTORS
- TRIPLE-BALANCED GEOMETRY (SEPARATE GROUND-REFERENCE CONDUCTOR)
- FEP AIR-TUBE INSULATION (FEP IS A FLUORO-POLYMER)
- CARBON-BASED 8-LAYER NOISE-DISSIPATION SYSTEM (NDS)
- DIELECTRIC-BIAS SYSTEM WITH RADIO FREQUENCY TRAP
- WEL-TYPE DOUBLE-CONTACT COLD-WELDED REUSABLE PLUGS, HANGING-SILVER PLATING DIRECTLY OVER MACHINED SOLID EXTREME-PURITY RED COPPER
I have heard that Adam Shaw is good as a "stand up artist". I look forward to it. The Audioquest "marketing slogans" are really "awful" to read. I have heard good thing about their headphones…...maybe a good one for Whammy as it is difficult to make headphones as "DIY"?
The screened power cord cable I got last time was from Supra Cables. Good quality at reasonable price…...but not as cheap as the Mouser cable.
The screened power cord cable I got last time was from Supra Cables. Good quality at reasonable price…...but not as cheap as the Mouser cable.
If a 1M cable can make any measurable difference in radiated noise of a PSU, RF or audio band, the PSU is in need of attention and proper engineering.
Cables as jewelry? That's a perfectly valid reason. Some cables are very attractive.
Recent I had a "power cord cable experience" after building the BA3-pre. I had my ear as close to the tweeter as possible and in left I just heard a very silent white noise (no music was playing of course). Then in right tweeter I could hear a bit more noise and not just white noise but noise originating from 100 Hz rectifier circuit. I then noticed that an unshielded power cord cable from one of the PSU's was going along with the speaker cables. I moved the cable 30-40 cm away and then the 100 Hz noise was gone. After this experience I invested in a couple of shielded power cord cables…….and these cables also just looks good! ….and has very good connectors.
Paul McGowan of PS Audio has said (in a YouTube video I believe) that shielded cables shouldn’t be used for power amplifiers power cords as it might attenuate upper frequencies. Has anyone had any experience with this or can they explain how this may be? I know that cables can be a touchy subject, but I can say that I did have one experience where the cable from my airport express attenuated the treble. It was a “cheap cable” and I replaced it with a $20 cable from amazon and the treble was better. I’ve read that the capacitance of the cable can have this effect?
Even with shielded power cord cables my MoFo can still produce 100 kHz square waves into 4-8 ohm load. That is treble enough for me. As long as the capacitor bank at the DC side of the PSU are full loaded and ripple is in the mV area the amp is ok. Also class A amps with its constant bias current the music signal should not have any effect on the current draw from PSU?
A testable hypothesis!
Obtain two power cords, one shielded ($13 @ Mouser) and the other not. Listen with one power cord and then with the other. Do you hear any difference? If so, do you prefer one over the other?
Beware, if you hear no difference, it does not guarantee that another listener with a different amplifier, will also hear no difference. Maybe you've got a well-designed amp ahd he has a manure quality amp. Or vice versa.
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It will be their cables I am sure. I don't know about the equipment. Probably brands the HiFi shop has in their sortiment. The time is limited to a couple of hours so they run the show. If I can hear a difference I don't mind to buy a cable just to try it at home. I am not a "cable believer" but always open to learn something new.
darrr, the recommended transformer for M2x has two secondaries, each 18VAC, rated for at least 8.5 amperes per secondary (i.e. 300 VA total). Since an 18V RMS sinewave has peaks of plus and minus 30 volts, I strongly recommend choosing rectifiers rated for 200 volts or higher. That gives a margin of safety. I also recommend choosing rectifiers rated for 10 amperes or higher, continuous DC current. That gives another margin of safety.
I happen to prefer the bridge rectifier package called "GBPC" because I find it easy to bolt to a chassis and easy to connect 1/4 inch "FastOn" connectors to its terminals. An example datasheet is attached.
Notice that these bridges are rated for 35 amperes (!!) which is comfortably higher than my recommendation of (10 amps or higher). Part numbers are available which guarantee 400V, 600V, 800V, or 1000V operation; again this is comfortably higher than my recommendation of (200V or higher).
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I happen to prefer the bridge rectifier package called "GBPC" because I find it easy to bolt to a chassis and easy to connect 1/4 inch "FastOn" connectors to its terminals. An example datasheet is attached.
Notice that these bridges are rated for 35 amperes (!!) which is comfortably higher than my recommendation of (10 amps or higher). Part numbers are available which guarantee 400V, 600V, 800V, or 1000V operation; again this is comfortably higher than my recommendation of (200V or higher).
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