Since asking for what is best in an audio forum is like asking what is god, I suppose the question could be rephrased as what is your opinion as to what provides a good balance between both- accuracy first, color second- as I imagine a lack of accuracy could also be defined as color by the one listening.
What do you do and what are your requirements when building for yourself?
Would you rather have generic film caps with 1% matching between channels, within 5% of the specified value on board or a set of more inaccurately matched mundorfs or whatever your expensive preference is?
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Matched generics, no question.
(where "generic" = Epcos, Wima, TDK, Nichicon, Panasonic, Cornell Dublier, Vishay, Kemet, etc...)
In my opinion, expensive caps are 1) tone controls and 2) good for managing expectation bias.
EDIT: In a phono preamp, particularly in the RIAA, I'd much rather have generics than audiophile caps even if both were matched within .1% . Perhaps a fancy-pants cap on the output if one needed color to taste.
I've been through the expensive cap phase of this journey, mostly it's just expensive. (But they do look cool...)
(where "generic" = Epcos, Wima, TDK, Nichicon, Panasonic, Cornell Dublier, Vishay, Kemet, etc...)
In my opinion, expensive caps are 1) tone controls and 2) good for managing expectation bias.
EDIT: In a phono preamp, particularly in the RIAA, I'd much rather have generics than audiophile caps even if both were matched within .1% . Perhaps a fancy-pants cap on the output if one needed color to taste.
I've been through the expensive cap phase of this journey, mostly it's just expensive. (But they do look cool...)
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I agree with 6L6. The build guide for this particular project encourages use of "boutique" caps, so I used some because it's fun (as long as the $$ doesn't get crazy), but if you want to select caps based on objective merits: first the only places where boutique caps are encouraged are coupling caps, inter-stage and output. Any cap of the right value (and as a rule bigger is better for that role) and a high-quality, low DA, dielectric (like polypropylene or teflon) should be fine. And yes, you are right, close tolerance and matching between channels is probably far more important than any "secret sauce". Still, it is fun to play with these things...
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The amp cases are fine with plenty of space. The psu case is just big enough thing just fit and was sized to accommodate the transformer that I used which is one of these.
Standard Range Toroidal Transformers: CM0120230: 120VA 230v to 2x30v
Standard Range Toroidal Transformers: CM0120230: 120VA 230v to 2x30v
polypropylene is lower distortion than polyester in some locations in a filter. In other locations they perform equally well.
In a RIAA you really need the same accuracy for capacitors as you do for resistors. Try to get 1% accuracy for both. and a little better if you can manage that.
Matching between channels is simply limited by your tools and methods.
You can get very good matching between channels.
Once you have good commercial quality resistors and capacitors that are each selected for the duty they need, then in my view there is no advantage in choosing expensive components just because they are expensive.
All components must have parameters that suit the duty !
Others agree:
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In the build guide it mentioned 28v transformer for MM and 36v for MC. Why did you use 30v?
Is there a measurable quality difference when using MC with psu at 30v?
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Hi Tubenstein,
You need to follow FSP Manual and go to Notes/Gain section to set it up for you cartridge needs - MM/MC, high/mid/low outputs. R1 is a cartridge load resistor and its value is also depend to your cartridge load specification. MMs are uses 30k-100k, 47k is the most common value. MCs are uses much lower load resistors. Go for your cartridge spec.
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Question about measuring and matching low capacitance values.
I'd like to get a meter which measures down below 200pf with hi accuracy. Seems even models like BK 886 don't go below this value as per spec sheet? Also the DEE and Mastech modes that seem to be popular list this as lower limit. Why is this so? If it were just an issue of cable capacitance the models with direct input slots should get around this.
If someone could recommend an ideal choice in a moderate price range that's relatively portable (Bench top ok but handheld preferred) that could also do In circuit ESR duty ideally I would be very appreciative!
I was looking at the der ee de-5000, the BK 885, etc.
Edit: I don't mind spending more if it will provide more utility down the road and spare me from the purchase of yet another device. I've already been through getting a cheapo meter which has provided less than satisfactory results. I'm a novice so my needs are more simple now, and I'm unsure what functions to anticipate needing as I make my way here.
I'd like to get a meter which measures down below 200pf with hi accuracy. Seems even models like BK 886 don't go below this value as per spec sheet? Also the DEE and Mastech modes that seem to be popular list this as lower limit. Why is this so? If it were just an issue of cable capacitance the models with direct input slots should get around this.
If someone could recommend an ideal choice in a moderate price range that's relatively portable (Bench top ok but handheld preferred) that could also do In circuit ESR duty ideally I would be very appreciative!
I was looking at the der ee de-5000, the BK 885, etc.
Edit: I don't mind spending more if it will provide more utility down the road and spare me from the purchase of yet another device. I've already been through getting a cheapo meter which has provided less than satisfactory results. I'm a novice so my needs are more simple now, and I'm unsure what functions to anticipate needing as I make my way here.
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So you use the same voltage to power both stages? You only used one FSP board?
I'd rather have a tighter fitting power supply that I can tuck out of the way.
I was debating using a different supply for each cartridge type as per the guide.
Also makes sense in case one of them goes to a new home and pare down my slew of spare cartridges.
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Hi spaceistheplace,
You're talking about Fluke or Keysight now. No one else makes anything with high accuracy. These will be out of circuit measurements.
If you are looking for actual, real high accuracy instruments for measuring capacitance and dielectric absorption, you are into bench instruments only. May as well get an LCR meter so you can deal with inductors and resistors at higher frequencies too. I would recommend a used HP 4263A (or Agilent - same company), or a new Keysight. Keysight is the current name for HP / Agilent test equipment. They tend to last forever, so it's a great investment.
I used to sell B&K and other instruments, and worked as a calibration technician. I've had to work with most brands and could see easily which instruments were accurate, but more importantly, which instruments held their calibration. There isn't any point in getting an instrument that you can't depend on. Most hand held LCR meters (don't bother with ESR meters, they don't measure the important parameter - dissipation, or D/A). Take your time and look carefully at the specifications and compare them with what your plans for the instrument are. It's important to get a reality check before sinking money into you meter. One thing to watch closely are the error limits. You may find that that nice 4 1/2 digit display only has two significant digital and the rest is for show. You will need a test fixture or Kelvin leads. These will be four-wire measurements.
-Chris
You're talking about Fluke or Keysight now. No one else makes anything with high accuracy. These will be out of circuit measurements.
If you are looking for actual, real high accuracy instruments for measuring capacitance and dielectric absorption, you are into bench instruments only. May as well get an LCR meter so you can deal with inductors and resistors at higher frequencies too. I would recommend a used HP 4263A (or Agilent - same company), or a new Keysight. Keysight is the current name for HP / Agilent test equipment. They tend to last forever, so it's a great investment.
I used to sell B&K and other instruments, and worked as a calibration technician. I've had to work with most brands and could see easily which instruments were accurate, but more importantly, which instruments held their calibration. There isn't any point in getting an instrument that you can't depend on. Most hand held LCR meters (don't bother with ESR meters, they don't measure the important parameter - dissipation, or D/A). Take your time and look carefully at the specifications and compare them with what your plans for the instrument are. It's important to get a reality check before sinking money into you meter. One thing to watch closely are the error limits. You may find that that nice 4 1/2 digit display only has two significant digital and the rest is for show. You will need a test fixture or Kelvin leads. These will be four-wire measurements.
-Chris
Chris thanks for the response. The HP 4263A is about 1K used even without the breakout box for parts testing. Also I worry about something used that's not recently calibrated and additionally thats a little outside my budget for this.
There's a handheld by keysight the U7132C in the ~400 usd range. Would this be a reasonable compromise for an audio hobbyist not looking for a giant pro unit?
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There's a handheld by keysight the U7132C in the ~400 usd range. Would this be a reasonable compromise for an audio hobbyist not looking for a giant pro unit?
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Hi spaceistheplace,
Yes!
The 4263A is the one I use all the time after my 4261A was damaged. It's a great LCR meter. The hand held should be more than fine. The Keysight name is on it, and from my long experience with that company, it will be an excellent tester.
Hi Andrew,
Never forget to do at least an open - short compensation on the test leads at each frequency. Mine has a 100KHz range that can not be used with my Kelvin lead set, so make sure your testing is valid. The fixtures that mount on the front of the unit can be used up to 100KHz.
-Chris
Yes!
The 4263A is the one I use all the time after my 4261A was damaged. It's a great LCR meter. The hand held should be more than fine. The Keysight name is on it, and from my long experience with that company, it will be an excellent tester.
Hi Andrew,
Certainly. Get them tested on a new or in tolerance capacitance tester. Pay attention to the test frequencies and test at as many as you reasonably can, but more importantly, at the frequency your tester is using. HP / Agilent / Keysight or Genrad would be great. You have some excellent brands on your side of the pond that we don't see as much over here. Any solid test and measurement company should make a good meter. Not too sure about Philips though.
Never forget to do at least an open - short compensation on the test leads at each frequency. Mine has a 100KHz range that can not be used with my Kelvin lead set, so make sure your testing is valid. The fixtures that mount on the front of the unit can be used up to 100KHz.
-Chris