Yes, parallel. But stack them on edge so that each cap is soldered to the pad. On edge has less inductance than on top.
You should be able to fit 3, or maybe 4, side by side on a pair of pads.
sorry to tell you.because in my country is very difficult to get any part of the amp.for resistor capacitor I cannot choose like vishay wima caddock etc.just plain component with no vendor name.for lm3886 I must import from singapore and the price include shipment is tripple hahaha. i cannot
Hi Bingbing,
you can use the 'On a budget' BOM as a starting point for type and specs of parts and then buy what is available of the same type.
BTW, you don't have the boards, right?
If it's so when you buy boards I can buy for you parts, at cost.
bingbing isn't the only guy with parts problems. Some evil person is buying all the On Semi MUR820's from Mouser and Digikey and there are none available. I have Taiwan Semi MUR820's in my cart, but I haven't released the order yet. I looked at both spec sheets and they seem at least comparable, nearly identical. I'm not exactly sure what might be a critical spec for a diode. Anything to worry about?
For some of you, reading a spec sheet is no more confusing than reading a newspaper. For many of us, however, it can be fairly bewildering. I also suspect that many in this group are not completely comfortable with buying on spec alone. If there is one thing I've learned from building all these MyRef's, it is that parts with adequate specs are not always the best sounding ones. The amp will certainly work and sound pretty good, but there are parts that will make it sound better, so spec's alone don't tell the whole story. For one example, lead material makes a difference in how a part sounds, but it is seldom thoroughly described, and all other performance characteristics may be superlative. Buy a resistor with .0001% tolerance and 2ppm TC, but steel end caps and inferior leads--live to regret it.
Peace,
Tom E
For some of you, reading a spec sheet is no more confusing than reading a newspaper. For many of us, however, it can be fairly bewildering. I also suspect that many in this group are not completely comfortable with buying on spec alone. If there is one thing I've learned from building all these MyRef's, it is that parts with adequate specs are not always the best sounding ones. The amp will certainly work and sound pretty good, but there are parts that will make it sound better, so spec's alone don't tell the whole story. For one example, lead material makes a difference in how a part sounds, but it is seldom thoroughly described, and all other performance characteristics may be superlative. Buy a resistor with .0001% tolerance and 2ppm TC, but steel end caps and inferior leads--live to regret it.
Peace,
Tom E
Taiwan Semi parts will work (and sound) fine (they're indicated on the 'On a budget' BOM) or you can buy the alternate part indicated in standard BOM, BYW29 (Mouser: 771-BYW29E-200).
I didn't compared OnSemi MUR-820 Vs NXP BYW29 directly but I've built some FEs with NXPs without any obvious difference.
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It should be fine, and so should the MUR840/860/8100 or similar - the only difference is the reverse blocking voltage. They were probably all made in the same process, and just binned differently after random sampling and testing. There's also a Fairchild part with exactly the same specs as the MUR860 (including non-magnetic leads and body).
May just be superstition, but I prefer the NOS ON Semi MUR8xx with the heavy copper tab and shiny plating - Gresham's Law in action. That may also be the reason that Mouser and Digikey ran out of stock.
Have to agree - there are no-name non-magnetic resistors that sound better than branded, hi-spec resistors with magnetic leads and/or end-caps.
The V1.2 to V1.4 Rev C boards do allow the use of a single bridge rectifier as an alternative to individual rectifier diodes. However, it's hard to find a fast-soft bridge rectifier with specs comparable to a single TO-220 fast-soft rectifier like the MUR8xx. You could use a generic bridge rectifier, but it doesn't save much on cost compared to 4x fast-soft rectifiers, while increasing the background 50/60 Hz and higher harmonic interference a bit. Whether that's acceptable is a matter for individual builders to decide.
(In the FE, you would need 2 bridge rectifiers, one for each rail, so the economics may favour a bridge rectifier if the sonic disadvantages are not considered.)
A single bridge rectifier @ ~£1.50 each, is a lot cheaper than 8 rectifier diodes @ ~£1.00 each.
That's ~£13 ($20) saving in a dual mono amplifier & ~£14.50 ($22) saving in a stereo amplifier.
Does a 50ns diode make a quieter supply?
Does a MUR (not a MSR) as a softer diode make a quieter supply?
Does an MSR as a soft diode make a quieter supply?
That's ~£13 ($20) saving in a dual mono amplifier & ~£14.50 ($22) saving in a stereo amplifier.
Does a 50ns diode make a quieter supply?
Does a MUR (not a MSR) as a softer diode make a quieter supply?
Does an MSR as a soft diode make a quieter supply?
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The prices in moderate quantities are closer - a 10A, 400V bridge rectifier runs to about $0.50 in 10 qty, while 4x 8A, 600V fast-soft rectifiers runs to about $1 ($0.25 each) in 50 qty. So it's about a 2x differential in price, but not very much in absolute terms - just 50 cents per channel for Rev C, and $1 per channel for FE.
No idea about the MSRs, but an MUR860 bridge with a single 100nF snubber generally gives a lower audible noise floor for the background 50/60Hz harmonic hash. Whether that's worth the price is up to individual builders to decide. FWIW, my standard kits (which are value-oriented) include a generic bridge rectifier, while the premium kits include fast-soft rectifiers (and numerous other upgrades).
There's not much space on the V1.2 board, but it's possible in principle if you use a separate perfboard for each FE regulator (one for each rail, +14V and -14V).
You can also retain the +12v zeners, and remove the resistors and replace with two LM317 + resistor CCS. This can be done with some careful lead-bending and soldering, directly on the V1.2..V1.4 boards.
Sure you can, in principle.
I would use 12V zeners (you don't have the limiter
) and it will be not an easy task to fit it on 1.2 boards but it's possible.Thanks for your answer.
Yes I think I'll use separate perf board.
Do you think its better to use 12V zener than 14V like in FE board?
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I think I've got the answer from Clave.
Thanks Clave!
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Hi Linuxguru, Dario and others!
I have an idea to make separate board for PSU and move Main Audio Ground (MAG) from main filter caps to amplifier PCB.
I think it's better because the ground will more "clean" from noise.
What do you think guys?
I have an idea to make separate board for PSU and move Main Audio Ground (MAG) from main filter caps to amplifier PCB.
I think it's better because the ground will more "clean" from noise.
An externally hosted image should be here but it was not working when we last tested it.
What do you think guys?
