[sachu]

I was wondering about using some high quality parts that I was planning to buy to use in a build was hoping i could get some feedback and views from the folks here. I am sure it has been hashed out a few times on diyA, but haven't seen too many on HF.
 
 
1> PRPs  of Takman for the amp section ...which is better or is there something else that could be used? What advantage if any would there be over say the CFM55 from Vishay
2> Rikens (one or two in the signal chain, where would it be best used)
3> Allen Bradley carbon resistors for the PSU
 
As for capacitors I am thinking of using Elna Cerafines or the SIlmic 2s with Nichicon Gold tune for the rail stiffening caps.
 
 
Any opinions on any of these?
 
Appreciate it.

 

[slowpogo]

It would help to know what exactly you are building.
 
I used some small-value Rikens in my Millett Max Hybrid, as the output resistors.  I thought they added just a *touch* of depth and sweetness to the music that was absent when they were missing.
 
I like PRP for the simple fact that they are red and look cool - and are basically the same price as the ugly brown Vishays.  I have not done any direct comparisons against PRP, but I'm pleased with all the builds I've used them in.
 
I wouldn't use Allen Bradley or any carbon film resistors.  They drift over time and they really just introduce noise.  That noise might be desirable in, say, a vintage tube guitar amp, where using modern resistors would not sound 'authentic.'  But for a modern listening rig, I wouldn't use them.  Even those Kiwame carbon comp resistors - I thought they just smeared and fuzzed up the entire signal on my Millett.
 
I would primarily use something like Panasonic FM in the power supply...if you have multiple cap positions to fill, maybe use a pair of Elnas alongside a majority of better-spec'd caps like the Panasonics.  I have tried the Nichicon Golds before and frankly I was not impressed.  They sounded less harsh than standard non-audio caps, but not particularly good.  Nowhere near as good as the Elnas or Muse/ES varieties anyway.
 
If you're talking about using the electrolytics as output caps, I think a mix of Cerafine and Silmic II is ideal (now that Black Gates are getting hard to come by).  If your build only has one position for the output caps, try and find a way to parallel the Cerafine and Silmic II.  I find the Silmics have very lifelike timbral texture, but are otherwise a little too warm and lacking in detail.  The Cerafines are crisp and detailed, similar to Black Gates, with good texture in a different range than the Silmics - also a very tight soundstage and cool overall sound.  The two types together really balance each other out nicely.

 

[sachu]

Thanks for that..my reasoning for the PRPs is the same as yours  The PCB being all black makes it all the more appealing.
 
I guess I will skip the rikens in the gain and put them on the output. I have used them in the input positions in 3 of my builds so far and have been very happy with the results.
 
The caps is exactly what you point out, a mix of cerafine and Elna SImlics in the amp circuitry. Will look up the Pannys for the PSU.. Thanks

 

[tomb]

Be advised that the PRP may look cool, but their quality control will drive you crazy.  After building a few amps with them, Colin Toole and I quit using them because of that.  The epoxy shell appears to be dripped on with very unpredictable results.  It even affects how well you can solder them to the board.  As for any improvement over V-D's, we couldn't tell any - so the "cool red" was not enough of a benefit for the nuisance of dealing with misshapen resistors all the time.
 
I agree with slowpogo on the rest: FG's are pointless in the PS, and A-B carbons in a PS circuit would be ill-advised.  You may find Nichicon UHE's in more sizes than the Panasonic FM's and many of them come very close to the outstanding ratings of the FM's.  I agree that Elna Silmic II's are the way to go with Black Gates gone from the market, but ES's when properly bypassed can do very well. 

 

[sachu]

Hmm..well you are the second person to warn me about the fragility and poor QC of the PRPs in as many days. 
Guess will stick to the VD CFM55. Are the takmans any better though?
 
About the KGs, I've been reading at places people recapping the PSU caps with KGs and bypassing them with a film cap claiming amazing results. Also the values indicate more a use for PSU caps than anything else. Could you elaborate on your disagreement here.
 
I read in a couple of places where folks posted measurements of the A-B versus the Holcos and Mills showing a ringing effect with the other two while there were none in the A-B. 

 

[tomb]

Quote:

Hmm..well you are the second person to warn me about the fragility and poor QC of the PRPs in as many days. 
Guess will stick to the VD CFM55. Are the takmans any better though?
 
About the KGs, I've been reading at places people recapping the PSU caps with KGs and bypassing them with a film cap claiming amazing results. Also the values indicate more a use for PSU caps than anything else. Could you elaborate on your disagreement here.
 
I read in a couple of places where folks posted measurements of the A-B versus the Holcos and Mills showing a ringing effect with the other two while there were none in the A-B. 

1. I don't know anything about takmans, but having bought and sold a few thousand V-D's, I have no complaints - if it ain't broke ...?
 
2. OK - looks like you confused us on the Nichicon "Gold Tune."  The most common Nichicon audio-quality caps that are used around here are KZ's, FG's, and ES's (there are others, but those are the main ones you see the most).  The FG's actually stand for Fine Gold, so you can see the confusion.  I looked up the KG's on Nichicon's site (http://www.nichicon.co.jp/english/products/alm_larg/daia_f.htm), though, and once again - they appear to be audio-quality caps with no ESR or ripple specs published.  They seem to be quite large caps, however - most likely appropriate for power amps, not headphone amps.  With either one, though, the basic issue - and there were some posts about this recently - is that "audio quality" electrolytics are almost always deficient in ESR and ripple compared to quality "power" caps such as Panasonic FM's, FC's, and Nichicon UPW's, UHE's. (Low-ESR and especially low-ripple - are exactly the qualities you want in a power supply.)  In fact, they often don't even publish ESR and ripple data on audio-quality caps ... for an obvious reason.

 
Now, that said - there are certain places in a power supply (after an LDO regulator, for instance) where very low ESR is a bad thing.  That's not usually the case for a well-designed power supply where one would think the large electrolytics would go behind the regulator - providing ripple reduction right at the transformer output or basic line input.
 
One other instance I can think of would allow audio-quality caps to do well in the power supply - where the PSRR (Power Supply Rejection Ratio) of the amp circuit itself is not very sterling. In that case, the power supply impresses itself on the audio quality such that you may hear many of the components in the power supply.  IOW, the noise and distortion from the power supply parts would be in the audio band.  In that case, you may want audio-quality caps all the way through the amp - power supply to output.  In those cases, you may very well get noticeable results with esoteric caps and bypass arrangements.  Most designs you see around here have very excellent power supply rejection ratios, however, and the object is to use the best ESR/ripple performing caps such as FM's, FC's, UPW's, and UHE's (because you won't hear the difference in the audio band).
 
3. I'm not sure about ringing with Holco's or Mills.  If I'm not mistaken, those are wire-wound resistors that have been carefully tuned to make the inherent inductance of wound-wire very low.  I think they have other wire-wound resistors made by those companies that are not necessarily tuned for audio purposes and could have some nasty inductance properties.  Maybe someone bought the wrong kind once and started blaming all Holco's/Mills.  That's just a guess, though.  I know MOSFETs are fast enough that they will oscillate (ringing) with resistors and resistor values that work just fine for BJT's.  So maybe that could explain some of the stories you heard or experiences, too.
 
 
EDIT: If you're in the range sizes of those KG's, then you're talking about something other than than the typical miniature electrolytic.  That means my references toward FM's, FC's, UPW's, and UHE's won't apply.  Still, you should probably look for caps with good ripple and ESR specs unless the cap is specifically in the audio path of the amp circuit.
 

 

[nattonrice]

If you like red then prp is great. However as mentioned above the epoxy casing sometimes looks like a badly dipped candle.
I have used a couple of hundred and out of the ones I used I think ~5 looked odd to say the least.
It is more of a problem with the 0.25w than the higher ratings as far as I can tell.
 

 

[Pars]

I've never had a problem with the PRPs, though I do note a lack of uniformity in the coating on some. The Takman's are carbon resistors? Those will provide some damping where a metal film will not. Mills are non-inductive wirewounds; Holco's are metal film.
 
Nichicon makes some PSU oriented members of their audio series, which I believe the OP was referring to. From Michael Percy's catalog:
 
The KG Gold Tune & Super Through series large can electrolytics are Nichicon's premier power supply types for high end audio equipment up to a maximum 100VDC rating. All are solder lug except some smaller KG types which are snap-in (♦) where noted. The Super Through have gold plated solder lugs. All are ±20%, 85°C.

 

[dbfreak]

Speaking of Nichicon Super Through series, here's a handful of what they're made of (15000 uF - 50V):
 

 

 

 

[AmCan]

Thanks for those pictures on the Nichicon KG Super Throughs. Would you please elaborate on your ESR reading and what your impressions are of the insides of the can. Are these good or bad? I was going to select these for my Power amp but have been trying to find data on the ESR values. The Mundorf HCs are more than double the price. Thanks

 

[fzman]

Sachu,
 
I've been a strong believer in using better parts, but some common sense helps the wallet and the performance of the gear.  For caps, I like the Silmics, and FMs.  Depends where they go in the circuit.  Even in the psu, the caps closest to the devices are the most important sonically, so plan accordingly.  Use tight tolerance resistors, even match them, for good channel balance at critical locations.  More importantly, try to use circuits that are not so fussy about specific parts.  if it sounds good using "rat shack" parts, then cherry pick your spots, and try a few alternatives to get the voicing dialed in to your taste.
 
I am not a huge fan of the prps either- i like the v-ds, and if you want to go crazy, Caddocks, tantalums, or even vishay bulk film from texas components.
 
FMs are really good in psus, and silmics sound pretty good in the signal path.
 
hope that helps a bit.
 
cheers!
 
Mark

 

[eimis]

Quote:

 

 
For some reason it looks delicious to me