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G'day all, I wasn't happy with the sound of one of my DIY MM phono stages so I decided to completely change the RIAA network values to the same one's used in the excellent Bruce Heran op amp design.  I had to 'redesign'

the circuit board slightly, but all was eventually done ok, although I now have a question.  The Heran design RIAA network consists of two cascaded RC networks and the question, is the position of the network 'reversible' with respect to the op amp output and inverting input.  I did try this....and I'm not sure about this.  Can anybody definitively answer this question?  Regards, Felix.    

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Nothing wrong with either approach in my opinion Felix.   An accurate system can be very satisfying, as can a 'beautiful' system. Loudness buttons, tone controls, overblown midranges ,can al

No need whatsoever to apologise for who you are mate. Your posts often invite really good discussions. I have an Aspergers family member and they have the most enquiring and agile intellects around.

CDs are convenient.  The only thing delicate about them (assuming they are not abused) are those horrible jewel cases.  You open the case, put it in the player and use the remote from your listening c

If the network consists of two Parallel RC networks in series between the Op-Amp output and the inverting input, with or without an additional series resistor then YES you can reverse the order of the individual Parallel RC Networks.


 

 

The thing to consider is the physical size of each parallel network, as the inverting input may pick up interference if a network with a large physical size is connected, I would connect the larger network to the output and the smaller to the inverting network.
 

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G'day all, thanks for all comments.  This is actually quite interesting to me, as from the past I am aware of at least one phono stage design with the first RIAA stage dealing with the treble EQ,  followed by the bass EQ in the second stage with the claim of much lower record scratch being evident, yet I have seen the same circuit approach analysed negatively.  Interesting.  Regards, Felix.   

Edited by catman
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G'day all, a bit of a conundrum in a sense.  Two cartridges that I really like (ok....love) equally, the Shure M97xE and the Ortofon Super OM 10. 

 

I find both of them very sonically satisfying in just about every way.  They both sound their best with careful capacitance loading (especially the M97xE), but I could happily live with either one in all honesty.  Interestingly enough although the M97xE is often called treble 'soft', I honestly don't think that it is, assuming optimum capacitance loading, (possibly that is a big assumption). 

 

In fact I do regard the M97xE with the OEM elliptical stylus as sounding particularly 'nice' in the treble range, without sounding dull or 'soft' in the slightest!  A very musical sounding cartridge! 

 

If anything, the Ortofon Super OM 10 is a bit more 'neutral' but still musical, if that makes any sense!  I do love them both.  Regards, Felix.   

Edited by catman
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  • Marc changed the title to Catman's Analog Musings

I have both these cartridges, but haven't played with capacitance load.  Might I suggest the cheap AT3600 as being just as 'nice'.   Also, the older Shure carts, such as the M75/91/95

 

 I would not put any in the same league as my Stanton 681eee, or even less so, the AT440MLa/b,   but they find regular use on my 'other' turntables.

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G'day all, no real conundrum really, it's just that two cartridges with distinctly different sonic signatures can be equally appealing and engaging.  I think that is quite interesting.  Regards, Felix.   

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1 hour ago, catman said:

G'day all, no real conundrum really, it's just that two cartridges with distinctly different sonic signatures can be equally appealing and engaging.  I think that is quite interesting.  Regards, Felix.   

 

It is.  In fact, I tend to use the cartridge most suited to the type of music I am playing.  Some are better for jazz, and acoustic stuff, others for classical, and others for rock.

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@catman I had a  M97xE once and thought it was very neutral and treble soft.

With you posting I know now I never got the capacitance right.

Maybe the  M97xE is more fussy than most cartridges to get this right, as there is so many conflicting reviews on this cart in the forums everywhere?

Edited by rocky500
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G'day mate, yes it is.  A situation possibly made worse by the fact that quite a few popular commercially made phono stages have default input capacitance values of 220 picofarads, and when interconnect and tonearm wiring capacitance are added, the overall value of input shunt capacitance can approach and indeed exceed 500 picofarads.  The Shure M97xE wants to 'see' around 250 to 300 picofarads 'overall' to sound its best.  Any more than that, and it sounds very 'wooly' indeed!  Regards, Felix.   

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G'day all, after a fairly tumultuous week for a few reasons including getting very annoyed by idiots and ultimately realising that it is not worth getting upset by complete fools, and there is always the Human Rights Commission to make a complaint to anyway, on this Friday evening (as I type this), the 'Carnival of the Animals' is playing on ABC Classic FM via my Tivoli One Radio, and it is a nice way to pass the evening and forget about everything!  Regards, Felix.    

Edited by catman
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G'day all, it is a common question as to when any given stylus needs replacing (at least in the case of a typical moving magnet cartridge anyway), and in the last week I replaced the stylus on my Shure M97xE in here on this system.  I wasn't sure of its length of use in absolute time terms but it still played quite normally, but subjectively it had played a lot of records! 

 

However the new OEM stylus sounds fantastic making the whole thing sound like a different cartridge, so obviously the old stylus 'was' worn.  Interesting!  I only have a simple pocket magnifier with which to view the stylus tip and I have no way to achieve greater viewing magnification, so 'when' is it time to replace a stylus due to wear which will inevitably happen if playing records regularly?  Regards, Felix. 

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worn stylus or worn suspension ?

 

in good quality cartridges that have not been abused, i've found the suspension gives up long before the stylus.

 

be wary of nos stylii

 

;)

Edited by michaelw
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G'day all, I have lots of good and very nice sounding MM cartridge phono stages and most of them are quite straightforward in terms of circuit design.  That is fair enough too, however there are situations where some 'refinement' and adjustability in design is indeed worthwhile. 

 

My Akitika Phono Z DIY phono stage is a good example of this.  Although quite conventional in many respects, the designer's use of 'electronic cooling' does reduce phono stage input noise quite markedly, a real plus with high inductance cartridges like the Shure M97xE.  

 

There are also extensive filtering options 'on board', that I personally don't really use, along with adjustable capacitance loading provisions (which I do).  All up a generally very useful range of user adjustable options.  I wish more commercially made phono stages followed the trends of the Akitika Phono Z.  Indeed some have, but most haven't.  Regards, Felix. 

Edited by catman
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G'day all, just reopening this thread.  The kit phono stage that I rebuilt was the PAIA phono preamp kit and after building it I just didn't like its sound.  I eventually found an interesting builders page that was quite interesting and showed good general performance and reasonably good adherence to the RIAA curve but with some significant lower bass roll off and upper treble boost. 

 

On paper, it didn't look so bad but it was quite audible, and to my ears, not particularly pleasant sounding both bass light and bright, simultaneously!  However completely changing the RIAA values has resulted in a phono stage that sounds wonderful to these ears!  So a db or so can subjectively make a big difference!  Regards, Felix.     

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G'day all, no real conundrum really, it's just that two cartridges with distinctly different sonic signatures can be equally appealing and engaging.  I think that is quite interesting.  Regards, Felix.   

 

Not at all. I've about 20 or so cartridges which I enjoy and many are really quite different to each other. Some suit rock, others Jazz, and a few do it all well. [emoji4]

 

I want to record them all for comparison purposes eventually. Maybe this weekend.

 

Sent from my Redmi Pro using Tapatalk

 

 

 

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G'day all, I was listening to The Beatles 'Abbey Road' last evening with my Shure M97xE with optimised capacitance loading and it sounded fantastic to my ears, yet it was 'easy' sound as defined by the Audiophile response curve as used by the Shure 'x' series. 

 

The interesting thing is that although the upper treble is indeed 'softened', it doesn't sound lacking at all, assuming optimum capacitance loading, of course.  I often wonder why Shure went from a ruler flat frequency response right up to 20 KHz during the Shure halcyon days, to the stated preference of the 'audiophile' response of latter cartridge years.  A thinking of the 'times' I guess!  Regards, Felix. 

Edited by catman
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Hello Catman

Just an observation here, I have seen you do a lot of posts about this sort of thing and it makes me wonder.

I mean, I put a record on and listen to just enjoy the music and if it hits that extra audio Nirvana then great.

The thing is I am not cluttering up my mind with thoughts of technical issues.

 

So just wondering if you ever just play music and enjoy the listen without thoughts of " optimised capacitance" etc. :)

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G'day mate, you're not the only person who has made that observation of which I am obviously guilty!  I guess this comes from my general sense of perfectionism and my general electronics training and knowledge. 

 

I'm sorry if this drives everybody crazy but this is all part of my Aspergers nature.  I frequently wish that I could be less critical too, but sadly 'it ain't gonna happen'.  Sorry!  Regards, Felix. 

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39 minutes ago, catman said:

G'day mate, you're not the only person who has made that observation of which I am obviously guilty!  I guess this comes from my general sense of perfectionism and my general electronics training and knowledge. 

 

I'm sorry if this drives everybody crazy but this is all part of my Aspergers nature.  I frequently wish that I could be less critical too, but sadly 'it ain't gonna happen'.  Sorry!  Regards, Felix. 

 

No need whatsoever to apologise for who you are mate. Your posts often invite really good discussions. I have an Aspergers family member and they have the most enquiring and agile intellects around.

Be proud and not apologetic:)

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5 hours ago, rantan said:

 

No need whatsoever to apologise for who you are mate. Your posts often invite really good discussions. I have an Aspergers family member and they have the most enquiring and agile intellects around.

Be proud and not apologetic:)

I do too, my nephew and he is uniquely brilliant! Rock on, Felix!:thumb:

Edited by stevoz
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G'day all, yep I really think so!  In recent times I've tried using my favourite sounding RIAA  EQ network as used in the Bruce Heran/ Mimic single op amp design into a number of my DIY phono stages, and they are sound the same and wonderful, despite using different op amps! 

 

It is perhaps interesting that apparently the RIAA response of that network whilst quite accurate does have 'some' slight ripples, and despite these ripples, sounds truly wonderful.  In contrast, phono stages with truly accurate RIAA curves I've heard do not seem to sound anywhere as good and musically satisfying as this one, and that is truly interesting!  Regards, Felix.   

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G'day all, more phono stage 'musing'.  Today I was in here doing a bit of record listening whilst rotating phono stages and I noticed something a little interesting about my DIY ESP P06.  The ESP P06 was my first really top notch DIY phono stage, and it remains a personal favourite and whilst other phono stages may sound more euphonically pleasant, the P06 has 'something' about it quite special and today that quality was quite apparent and this may indeed may show up a possible limitation with simple op amp feedback designs. 

 

Listening to the P06 I became aware of how 'open' and uncompressed it sounded compared to op amp feedback circuit approaches.  It is a quite subtle effect, but noticeable and it certainly adds to the listening experience with a sense of 'openness' and sonic effortlessness.  In comparison, op amp feedback designs although 'good sounding', tend to have a subtle sense of 'compression', if that makes any sense! 

 

The P06 does use part passive/part active RIAA equalisation with passive treble RIAA which I suspect is the reason for this sound quality.  To be honest I have heard a similar kind of sound quality with phono stages using full passive RIAA equalisation.  My ANT Kora 3T SE has full passive RIAA  equalisation, and sounds very similar.  Interesting.  Regards, Felix.     

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Hi Felix,

I've noticed (and enjoyed) your passion for exploring phono stages in the search for vinyl perfection, and I've also noticed that your knowledge and technical ability is respected and admired here and on some other audio sites. 

So I'm curious - after hearing and looking at the insides more phono stages than most people know exist, have you ever tried to design your own phono stage to create the best that can be?

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G'day mate, thanks for your kind comments.  As for design, well no, as calculating the RIAA equalisation network accurately is heavy stuff involving heaps of mathematics and I simply don't have the ability! 

 

However in terms of general concept, I like the idea of either full passive equalisation or hybrid RIAA equalisation as used in the ESP P06, for optimum dynamic and transient performance.  Due attention to optimum cartridge loading is also of critical importance, and at least with moving magnet cartridges, capacitance loading. 

 

Op amps are fine, if used appropriately, but discrete devices have their merits, sometimes using devices not often though of as being suitable for high quality audio work, the ANT Kora 3T SE being a fine example. 

 

Power supply should be high general quality and low noise along with attention to signal 'headroom' and supply voltage.  The use of 9 v battery supply rails, either single ended or bipolar, although 'clean', are frequently insufficient for optimum signal headroom capability.  Phono preamp design is indeed a demanding application.  Regards, Felix. 

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Can you ignore record scratches and just enjoy the music?

 

G'day all, I've just been listening to an old pressing of John Williams guitar and whilst it is a good recording and pressing in general terms, it does have a 'few' scratches. 

 

I will freely admit that in the early days, any record scratch would drive me crazy, but these days not so much.  I guess that I have learned to effectively ignore the scratches, and just enjoy the music.  It would be nice to not have 'any' scratches but I guess that in the real world...  Regards, Felix. 

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1 hour ago, catman said:

Can you ignore record scratches and just enjoy the music?

 

 

Simply, no! Well I can't anyway:D. I can handle the occasional crackle and pop, in fact on some 'mintish' LP's I welcome the crackle that reminds me, while I drift away with the sonic brilliance, that what I'm hearing is vinyl and it makes me smile:).......but in the case of a scratch that ticks like a dripping tap every 1.8 seconds, no. Drives me crazy......:wacko::P

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Different phono stages:  do they mostly sound 'very similar'?

 

G'day all, borrowing from a thread on another audio forum, this is actually a very interesting subject, as having 'more than a few' high quality phono stages myself, all operational, I find myself mostly in agreement with the thread title/question....with caveats. 

 

It is a fact that phono stages all nominally do the same job and 'should' sound very similar all things being equal, however I will admit that I do have my 'favourites' for reasons that may be slightly difficult to qualify/quantify.  Even slight variation from the standard RIAA curve may actually sound quite 'agreeable'. 

 

One very interesting point that I completely agree with on the other forum thread is the effect of 'suboptimum loading', especially capacitance loading with moving magnet cartridges.  This is a fact, and a very recent incident has once again proven the truth of that to me! 

 

Of the phono stages that I regard my best, other sonic factors apart from the precise RIAA equalisation predominate, but things do get very blurry here.  I think the word 'subtle' best describes these sonic differences.  Regards, Felix.     

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  • 2 weeks later...

G'day all, my apparently insatiable desire for different phono preamps has kind of burnt me out of late and I'm thinking of a 'single' desert island type of system that I would be happy with without any further changes.  With my unfortunate track record, at least when it comes to phono stages, that wouldn't be an easy task I guess. 

 

However after all this time and evaluating different phono stages, my favourite DIY ESP P06 of many years still ranks very highly along with my beloved Shure M97xE, so at least those two components have probably been decided!  Is my elusive search for record playback perfection on a reasonable budget all in vain?  Probably! :) Regards, Felix.            

Edited by catman
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Felix,

 

I am wondering how I might determine the capacitance loading of the built-in MM phono stage in my NAD C388? I can't seem to find any info about it, and am interested to know if this is something I can look at in improving the performance of a Rega cartridge?

 

Thanks

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G'day mate, I'm slightly guessing, but based on current day standard NAD practice, I'd say, very likely a value of around 200 picofarads at 47 k.  Regards, Felix.   

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Thanks. In your experience of all things Phono pre amplification, what would be a good DIY option to look at, hopefully able to compete with manufactured stages in the ~700-1000 range? or better.

 

And what does it take to build one effectively?

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6 hours ago, Gijo1977 said:

Thanks. In your experience of all things Phono pre amplification, what would be a good DIY option to look at, hopefully able to compete with manufactured stages in the ~700-1000 range? or better.

 

And what does it take to build one effectively?

Taking bets on the Akitika! 2 to 1 ;)........sorry Felix.:D:thumb:

Edited by stevoz
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G'day all, actually I had completely forgotten about the Akitika, to my complete shame!  Yes that one, and the ESP P06 and the Bruce Heran simple one  op amp design.  All three are superb!  Regards, Felix.   

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