Vishay foil resistors in my Acoustech phono

[brenden]

Hi guys ,I am in the process of changing the resistors and some caps in my Acoustech PH1 phono .

I have used hundreds of Vishays in the past and always impressed.In fact never got a disappointing result once .

I am about half way towards completing an all out mod for this phono amp . I listen to each change to be sure of the result ,and to learn what gives the best results ,but is very time consuming .

The results I am getting so far on this one is fantastic ,on an already exceptional phono stage.I still cant believe this kind of sound can come from op amps.

The power supply is basically a RCRC... design and I wanted to reduce noise from all possible sources in the circuit no matter how little as the MC is a little noisy with low output cartridge like my Denon DL303 so they were first to be changed.

Bass depth and weight increased dramatically ,and purity also benefitted .I was able to get some VTA 52, 1 watters for a couple of dollars each but they are big.Dont obsess about the type of vishay bulk foil you use ,they are all far superior to metal film.I have used RNC 90s, All the VTA series ,and S102 ,etc and the basic element is the same. Maybe some nude vishays in a really critical area like feedback in the op amp ,but otherwise the cheapest bulk foils I can find for a particular job.

The Acoustech simply uses 2 op amps ,and I chose to do this all out mod because the sound on the stock amp was excellent to begin with ,and I wanted a simple piece of equipment ,that if it broke ,it was an easy plug in op amp replacement to repair.Not much to go wrong elsewhere .The circuit board is also comparatively large and relatively easy to fit in some bigger parts ,although may have to raise the lid a little .

If you think op amps cant possibly be state of the art check out the Walker phono stage ,which is a refined version of the AHT non signature phono stage .Walker liked the phono so much he bought the company .The AHT was about $5000 ,and Walker is charging around $25000 for his version from memory .

My Acoustech amp started out with one channel down .Turned out to be corroded circuit traces in the power supply ,so I cut the offending traces and hard wired them.

I have replaced one resistor (1meg) in the audio circuit and it too made excellent gains in purity depth and inter note silence.Had to use 2 500k in series to get a meg

I have so far replaced one cap in the circuit with an Auricap .01 1500v because they are superb with a rich and sweet ,almost tube like character These make the music more real and lifelike particularly the high frequencies ,but absolutely no shrillness at all ,smooth as .The high voltage ones are better in my opinion.The .01 sound fantastic anywhere as bypass or coupling .I have used hundreds of the .01 and love them.Never get a bad result.

Warning ,these caps (and most others need burn in ),and will freak you out until they begin to burn in .The bass usually gets sucked out for some time ,and you will think there is something wrong ,especially in small signal equipment like a phono stage .The caps I used ,I took out of some other equipment ,but hadnt been used for years ,and I still had the problem .

The vishays will improve with time ,but sound great the second you turn it on.

The power supply uses Panasonic FC which are excellent ,but I may drop a Black gate in there somewhere to try out, as I still have a few in the parts box .Black gates and elna cerafines work best together .They balance out each others strengths and weaknesses .This is one of the secrets to the sound Marantz CD 94 .

Still have some work to go and very time poor.Hope to complete this in the next month or so.

[Addicted to music]

Nothing wrong with opamps!

I have experimented with a lot of op amps.

Can you provide a link on the resistors you are using for the upgrade please!

[Guest Muon]

Fun stuff, Brenden Oh, and welcome.

Someone here with a Jasmine Phono stage (jfet based) used the VAR naked resistors and like them a lot if I recall correct.

 

I started out with the Nichicon KZ caps in the power filter/decoupling, i then changed to Panasonic FC as I found the Nichicon's a little dry, but still not happy I changed to Silmic ll caps after remembering Allen Wright suggesting them on another forum, these are rich and detailed and just slightly warm compared to the FC and KZ. I thought about mixing Silmic and Cerefine but went with just the Silmics, but now you have me thinking of a Silmic/Cerafine combo again

 

Cap changes as you say can help too, I have tried a few and I have almost worked out a combo that I like.

 

Next I will try replacing some resistors, and the VAR types are still attractive for a few positions, the rest I might go with Takman REX.

 

Brenden, what caps are in the RIAA EQ in you phono?

 

Cheers

 

Edit: Ah, Wima polypropylene?

looking at the Stereophile review now, looks well made.

Edited June 12, 2013 by datafone

[brenden]

Nothing wrong with opamps! I have experimented with a lot of op amps. Can you provide a link on the resistors you are using for the upgrade please!

Hi Pchan, The resistors I have mostly used are the  Vishay VTA54 ,and VTA55 but other bulk foil packages are all superb. 

  

              They can be purchased from  places like Parts Connexion ,and Michael Percy ,who also has a cheaper conformal coated  version ,which are likely just as good ,but I haven't tried them just yet .

 

Dataphone ,yes they are Wima ,which they also use for bypass caps .For anyone on a real tight budget they are very good and you can afford to put them everywhere ,but if you want to step up there are better caps for more money .

 

   I also have a heap of the silmics in my parts box ,and you described them perfectly .Not too different to the black gates in many ways .

 

Glad I got you thinking ,because that was the aim of my post .

                          You can literally buy a simple  op amp phono kit for $30-$60 dollars and buy some top notch parts for a couple of hundred more and have an excellent piece of kit .

 

   or you can upgrade many of the op amp based stages  with better parts if you can solder .The Graham Slee ,could be a good candidate for some resistor changes for example.

 

   I have rarely heard of people using bulk foil resistors in the power supplies in audio ,but there are definite gains to be made .There is a reduction in grain ,or to put another way, more purity .

 

           The beauty of the op amp based designs is that they don't usually have many parts ,and even some expensive parts can be do-able within a reasonable budget .For novices ,they are great to work on ,because if you do something wrong ,$4 will buy a new chip , plug it in and you are on your way again .

 

  Those that own a good phono stage but want to upgrade   can spend a couple of hundred dollars on parts ,and have a vastly more enjoyable piece of equipment.

 

          I have read on many forums about people that knock vishays without even trying them ,after all " how much difference can they make",and "they are expensive" . Then they will talk about spending $1000 dollars on cable .

 

             Man ,you can buy a lot of vishays for that kind of cash .Like I said ,the different models have the same affect ,so don't obsess  about the differences in Vishay models too much .Get the cheapest you can ,they are all good . 

 

     Higher value resistors are  noisier ,so these are prime targets for replacement by the much quieter bulk foils ,especially if they are in the op amp feedback loop.

 

    MC stages have very high gain ,and any noise in the power supply and gain stages is multiplied by this high gain ,so these stages are critical for upgrades .

 

                                     

                                  Cheers .

[Addicted to music]

Brenden,

 

the vishays are great resistors even though i havent tried them, when i 1st started DIY in this hobby, I had a preamp that I build with carbon film resistors because thats what was supplied with the kit, I had to build a 2nd identical unit but this time with 100% metal film resistors, the difference was mind blowing, I really dont know why some diyers will opt for carbon film that has almost 10X the thermal noise than the metal film, using carbon film is so unrealistic especially with high gain stages for MC in the RIAA of a phono stage, it was truely black and white, the noise that exist in carbon film was so audiable, with metal film it was so much less, the sound was focus and sharp.  

 

Agreed with WIMA caps, but wont go to electrolytic in the signal path! 

 

Like you have tried numerous opamps, possible the best ones are the LME 49720/10  and the ADA 4627-1 brz, would also like to know what you have as opamps???

[Guest Muon]

I like some of the Wima's, decent caps at low cost.

[lovetube]

Hi guys ,I am in the process of changing the resistors and some caps in my Acoustech PH1 phono .

I have used hundreds of Vishays in the past and always impressed.In fact never got a disappointing result once .

I am about half way towards completing an all out mod for this phono amp . I listen to each change to be sure of the result ,and to learn what gives the best results ,but is very time consuming .

The results I am getting so far on this one is fantastic ,on an already exceptional phono stage.I still cant believe this kind of sound can come from op amps.

The power supply is basically a RCRC... design and I wanted to reduce noise from all possible sources in the circuit no matter how little as the MC is a little noisy with low output cartridge like my Denon DL303 so they were first to be changed.

Bass depth and weight increased dramatically ,and purity also benefitted .I was able to get some VTA 52, 1 watters for a couple of dollars each but they are big.Dont obsess about the type of vishay bulk foil you use ,they are all far superior to metal film.I have used RNC 90s, All the VTA series ,and S102 ,etc and the basic element is the same. Maybe some nude vishays in a really critical area like feedback in the op amp ,but otherwise the cheapest bulk foils I can find for a particular job.

The Acoustech simply uses 2 op amps ,and I chose to do this all out mod because the sound on the stock amp was excellent to begin with ,and I wanted a simple piece of equipment ,that if it broke ,it was an easy plug in op amp replacement to repair.Not much to go wrong elsewhere .The circuit board is also comparatively large and relatively easy to fit in some bigger parts ,although may have to raise the lid a little .

If you think op amps cant possibly be state of the art check out the Walker phono stage ,which is a refined version of the AHT non signature phono stage .Walker liked the phono so much he bought the company .The AHT was about $5000 ,and Walker is charging around $25000 for his version from memory .

My Acoustech amp started out with one channel down .Turned out to be corroded circuit traces in the power supply ,so I cut the offending traces and hard wired them.

I have replaced one resistor (1meg) in the audio circuit and it too made excellent gains in purity depth and inter note silence.Had to use 2 500k in series to get a meg

I have so far replaced one cap in the circuit with an Auricap .01 1500v because they are superb with a rich and sweet ,almost tube like character These make the music more real and lifelike particularly the high frequencies ,but absolutely no shrillness at all ,smooth as .The high voltage ones are better in my opinion.The .01 sound fantastic anywhere as bypass or coupling .I have used hundreds of the .01 and love them.Never get a bad result.

Warning ,these caps (and most others need burn in ),and will freak you out until they begin to burn in .The bass usually gets sucked out for some time ,and you will think there is something wrong ,especially in small signal equipment like a phono stage .The caps I used ,I took out of some other equipment ,but hadnt been used for years ,and I still had the problem .

The vishays will improve with time ,but sound great the second you turn it on.

The power supply uses Panasonic FC which are excellent ,but I may drop a Black gate in there somewhere to try out, as I still have a few in the parts box .Black gates and elna cerafines work best together .They balance out each others strengths and weaknesses .This is one of the secrets to the sound Marantz CD 94 .

Still have some work to go and very time poor.Hope to complete this in the next month or so.

 

interesting.

I like the Naked foil custom made resistors on my RIAA 0.05% tolerance .the best so far and I like the Mcap silver/gold/oil for all signal .

this is a full valves phono including valve rectifier with full 2 chokes filtering with one used at choke input  and still no where near 5k yet .

 

enjoy

Lovetube

 

[brenden]

Nice ,Lovetube.

 

                            These M caps are very well regarded ,but I haven't tried them yet .I have used the V cap Teflons ,and they are the best so far .

     

                          I have them in my Trivista 21 dac , probably worth the price of the dac LOL.

 

                                      For anyone that cant afford these caps ,the next best thing is to buy a .01- .1 and bypass the coupling caps of either the Mcaps Silver Gold  or the V caps  Copper  foil     .This will give much better sound at a very cheap entry.

 

                                         I have used bypasses to great effect lots of times ,and it is well woth it if on a tight budget ,  

 

                      I have just bought a few used Vishays on ebay from someone in China to try out  ,so well see how that goes .

[Nada]

              I like the Naked foil custom made resistors

 

Im going to get some of these for a little project later in the year so thought Id share the ordering info in case others want to try them.

 

The TX2575 'naked' foil audio resistor uses the latest Bulk MetalZ-Foil technology, providing  a combination of low noise and low inductance/capacitance

 

Very expensive for a resistor but not relative to other parts.  Best price?  Perhaps ordering direct:  TX2575

 

Anyone else used them and heard a difference?

 

Edited June 14, 2013 by Nada

[brenden]

Great work Nada ,thanks for that .It  will come in handy .I may try some in some critical spots ,to see how they compare, some time in the future

[Guest Muon]

I have heard them described as transparent, dynamic and musical.

[Addicted to music]

I have heard them described as transparent, dynamic and musical.

For up to $20US a resistor they f-----g better be!!!!

[Guest Muon]

I just wish I had have bought these and the Duelunds I need while the $ was on par *sigh*

[lovetube]

For up to $20US a resistor they f-----g better be!!!!

 

hahahaha .

yes they worth every cents .i use them in my GA reference phono stage , at that price don't expect to use them every where ( in fact some value I paid over $25usd each ) and don't expect to see them in preamp or poweramp under 10k.

 

Lovetube

[Nada]

For up to $20US a resistor they f-----g better be!!!!

 

That was my first response too. Then I reconsidered. Would you be bothered paying an extra 20 bucks for a cap that makes a discernible difference? What about if you have a two grand budget including mods and some NOS tubes for a preamp. Would  80 bucks to improve the sound by using great resistors in critical locations directly in the signal path be worth it?  If not just wait a year or two for the Chinese hand crafted clones at half the price.

[Guest Muon]

My fortnightly Ice Coffee budget would buy a few of these easy enough.

 

Reminds me, I need to give that stuff up.

[Once was an audiophile]

My fortnightly Ice Coffee budget would buy a few of these easy enough.

 

Reminds me, I need to give that stuff up.

Datafone i have about 8 x 100R your welcome to try them..................  

[Once was an audiophile]

For up to $20US a resistor they f-----g better be!!!!

Crap on any metal film from jaycar  

[Once was an audiophile]

I have heard them described as transparent, dynamic and musical.

Too many in a particular component and it becomes hifi like a sabre based dac with a pc feeding bits into it   

[Once was an audiophile]

 Black gates and elna cerafines work best together .They balance out each others strengths and weaknesses .This is one of the secrets to the sound Marantz CD 94 .

No black gates in a stock  marantz cd94 ..................

Edited June 14, 2013 by kajak12

[Guest Muon]

Datafone i have about 8 x 100R your welcome to try them..................

That's a value I was going to try in the signal path.

 

Yeah, too many could be too much, I agree!

[brenden]

 

No black gates in a stock  marantz cd94 ..................

Hi Kajak ,I stll have a few Black Gates ,but Silmics are similar .I love my 94 Mk 2 .

I also have a pile of big can Cerafines for power amps .Once I work out what I need in the future I might let SNA have a crack at them .

If too many Vishay resistors unbalanced the sound I would balance it back with some nice Silmics ,and really smooth Auricap bypasses .And if I had to , I would change a couple of Vishays back to tantalum . 

[brenden]

Sorry Kajak ,I misunderstood you ."No black gates in a stock marantz cd94 .................."

Yep ,there is a single one after one of the regulated power supplies .I had both a 94 ,and a 94mk2 .

[brenden]

or maybe it was just in the mk 2 .They both had them in when I finnished with them ,LOL

[Addicted to music]

Crap on any metal film from jaycar

And all the carbon and metal oxide film on the market that's marketed by fashionable cap companies! I just wonder why you haven't used there precision pots, sure beat the expensive rubbish that everyone else raves on about in these neck of the woods.

Oh BTW k12, these resistors comes as SMD, apparently the leads of the through the hole ones act like an antenna for thermal noise.

Edited June 14, 2013 by pchan