Pundit
Post by SL1210 on Jul 2, 2019 11:52:59 GMT 12
I used to have a valve Phonostage - the Fosgate Signature. It was quite a looker, not 100% quiet but good enough. Unfortunately I sold that when I got a valve pre-amp. I replaced with with the very excellent Benedict Audio Hothead. But now that I have upgraded the Pre to a solid state I am back to looking for a valve phono stage. I am not rabid about valves but it is nice to have them somewhere in the system. I don't mind second hand but it does have to be good quality and quiet. I had a gander at Supratek (http://www.supratek.com.au/) and am impressed by what I have read. That, however is stretching what I can afford. I have some nice gear that I could exchange if you are looking for: Solid State Phonostage: Benedict Audio Hothead or Perreaux VP3 . Pre-amplifier: Danile Hertz M6 or Ayon Eris. Technics SL1210 Mk5g (with damped chassis) in better than perfect nick. Oppo 105 Disc Spinner (maybe even an Oppo 205) Jamo Bookshelf loudspeakers, Spendor D1 Bookshelves.
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Post by cartridgeguyonline on Jul 2, 2019 17:02:57 GMT 12
Why not have a chat with colinf, he made my preamp with mm and MC phono inputs and I know he is working on a stand alone phono stage.
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Post by Owen Y on Jul 2, 2019 18:26:08 GMT 12
SL1210 - do you need MC gain? Or only MM? What cartridge/s do you plan to use?
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Pundit
Post by SL1210 on Jul 3, 2019 10:47:03 GMT 12
SL1210 - do you need MC gain? Or only MM? What cartridge/s do you plan to use? Hi Owen, I am MC only. I am not allergic to MM but have three carts and all are MC - Benz Wood, Charisma Ref-1, Ikeda 9TT. I really need the phono for the Ikeda.
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Post by Owen Y on Jul 3, 2019 12:48:40 GMT 12
OK - you will need a MC phono stage, which will be costly in valves - which normally require an inboard or outboard Step-Up Transformer - high gain esp for the Ikeda 9TT. If you use other (line level) sources also & would like valves somewhere in your system, then I guess you'd be best to have valves downstream a bit, maybe in the preamp or amp?
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Post by colinf on Jul 3, 2019 16:12:17 GMT 12
Hi SL1210, I make valve phono stages, a passion of mine, if you're interested. I've just made a MC direct to valve input phono stage for a friend in central north island. Being valve input with no transformers or jfets the sound is very transparent, but can be a bit noisy with cartridges less than 0.4mV output. I tested it with 2 cartridges, the Dynavector XX2 Mk2 and the Topwing Suzaku. The DV has 0.4mV output and works well with the valve input stage. But the Topwing, although it's an amazing cartridge, has a bit of noise with its very low output of 0.2mV with the direct to valve input MC. Although I do enjoy listening to it still (I can't live without the transparency!!!). The background hiss is about the same as the record noise. Most valve phono stages operate with MM-levels of 3mV or greater with satisfactory S/N ratio, and rely on solid state or transformer MC stepups for MC or low output cartridges. In developing a MC pre-preamp for my solid state MM phono stage I found that jfets have the lowest noise with the Topwing, and have next to no background noise. So in potentially making a valve phono pre for your Ikeda, with 0.17mV output, I'd use either jfet input or transformer input for lowest noise. But if you could put up with a bit of background tube rush, valve input MC is very clear. Cartridgeguyonline chose a Lundahl stepup transformer for his MC input phono pre.
AMR-iFi R&D
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Pundit
Post by SL1210 on Jul 3, 2019 19:47:16 GMT 12
Hi SL1210, I make valve phono stages, a passion of mine, if you're interested. I've just made a MC direct to valve input phono stage for a friend in central north island. Being valve input with no transformers or jfets the sound is very transparent, but can be a bit noisy with cartridges less than 0.4mV output. I tested it with 2 cartridges, the Dynavector XX2 Mk2 and the Topwing Suzaku. The DV has 0.4mV output and works well with the valve input stage. But the Topwing, although it's an amazing cartridge, has a bit of noise with its very low output of 0.2mV with the direct to valve input MC. Although I do enjoy listening to it still (I can't live without the transparency!!!). The background hiss is about the same as the record noise. Most valve phono stages operate with MM-levels of 3mV or greater with satisfactory S/N ratio, and rely on solid state or transformer MC stepups for MC or low output cartridges. In developing a MC pre-preamp for my solid state MM phono stage I found that jfets have the lowest noise with the Topwing, and have next to no background noise. So in potentially making a valve phono pre for your Ikeda, with 0.17mV output, I'd use either jfet input or transformer input for lowest noise. But if you could put up with a bit of background tube rush, valve input MC is very clear. Cartridgeguyonline chose a Lundahl stepup transformer for his MC input phono pre. Colin Thanks for your input. Basically I think I bit off more than I can chew. I am running it into a quiet Solid State MC phono and it has good sound. Output is low and I have to turn up my pre-amp. The end result is still quieter than my previous cartridge (Charisma Ref-1). So far so good, but what about valves. Very grateful for your insight and experience. If I understand you correctly it is possible to have a sort of Headamp / SUT even though it is a Moving Coil?
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Post by colinf on Jul 3, 2019 21:39:46 GMT 12
The amount of amplification required is very high for an MC-input phono stage, and single valves are generally out of their depth with S/N ratios for low output MC cartridges, but fine for MM. So to achieve the best S/N ratio with a valve phono stage you'd use a MM one with a transformer or an active MC headamp. I designed and made a low noise, high gain jfet MC headamp a few years ago which would work with most valve MM phono stages. Transformers can be good but the best ones can be expensive, and need lots of magnetic shielding to avoid hum pickup. To me they just slightly take something away from the sound, but can be better than jfets for tonal accuracy. It's also possible to design a low noise valve MC headamp which would use a lot of low noise valves in parallel to get the noise down to ok levels. That's something I want to do for my Topwing as well. It would probably have the best sonic transparency. It would also be elaborate and thus costly, but at it's eye-bulging retail of $11k the Topwing and others deserve it!
AMR-iFi R&D
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Post by Owen Y on Jul 4, 2019 12:46:12 GMT 12
I had a pal who had a custom Ecofan phono stage, which used many 6DJ8s in parallel to amplify his v low output Highphonic MC cartridge. It worked fine, except that a great deal of time was spent selecting / matching quiet 6DJ8s 
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Post by colinf on Jul 4, 2019 15:36:54 GMT 12
That would also be the case here, selecting quiet 6dj8s and paralleling lots of them for low noise. But with reliable modern 6dj8s (or ecc88, 6922 etc) that isn't so much of a burden anymore. What sort of output was the Highphonic?
AMR-iFi R&D
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Post by Owen Y on Jul 4, 2019 18:49:20 GMT 12
colinf I don't recall the exact model, but a number of the Highphonics were similar low output to that Ikeda - ie. in the order of 0.12 - 0.20mV 
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Post by michaelw on Jul 5, 2019 11:47:00 GMT 12
flashback to the good ol' days of cartridges with silly low outputs. ortofon were major offenders, with many cartridges outputting less than 0.1 mv i experienced an mc-3000 (0.1mv) into my arc sp8/2 (60db phono gain). feeding quicksilvers/maggie mg1b, noise was present but not intrusive. ditto my ortofon tmc-200 (0.09mv) into pureaudio vinyl (62db gain), pureaudio one, image pp2/mass. low output/moderate gain phono systems can work favourably. a long time ago while between phono stages, i used a koetsu rosewood into a nad 3020 for many months
happy days.
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Post by Owen Y on Jul 5, 2019 13:06:53 GMT 12
An aside: Back in '84, ARC introduced FETs into the SP-8 (phono & line sections) - maybe to lower noise. In the 'Rev E' version, usually referred to as the 'Mk II', as it involved a complete new PCB. I went down the track of buying all the parts direct from ARC, for upgrading my SP-8 'Mk I', but later changed my mind. In '87, ARC brought out the full FET-tube hybrid SP-9 preamp - it had >2 x the gain (67dB) & 1/50 the noise, but sounded... disappointing! Sorry, digression
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Post by jon on Jul 5, 2019 13:56:16 GMT 12
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Post by Owen Y on Jul 5, 2019 15:45:37 GMT 12
snewt, IIRC, Ken went down this track & built a His Master's Noise (HMN) phono?
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Post by colinf on Jul 5, 2019 17:13:18 GMT 12
An aside: Back in '84, ARC introduced FETs into the SP-8 (phono & line sections) - maybe to lower noise. In the 'Rev E' version, usually referred to as the 'Mk II', as it involved a complete new PCB. I went down the track of buying all the parts direct from ARC, for upgrading my SP-8 'Mk I', but later changed my mind. In '87, ARC brought out the full FET-tube hybrid SP-9 preamp - it had >2 x the gain (67dB) & 1/50 the noise, but sounded... disappointing! Sorry, digression IIRC the jfets they added were intended for protection of the 6dj8 cathode follower grid to cathode voltage before the heaters had warmed up fully. Previously there was a 1n914 diode there. The jfet was connected as a low capacitance diode in the same position and lowered distortion in the high frequencies a little. ARC put protection jfets in their poweramps of the era too, such as D70 mk2.
I thought the best of their hybrid preamps was the SP11 which used jfet inputs and unlike the SP9, triodes for the critical gain stage. The SP9 had cascoded mosfets for gain, and the lone 6dj8 was there to invert the phase inbetween stages.
AMR-iFi R&D
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Post by colinf on Jul 5, 2019 18:42:26 GMT 12
The HMN phono looks good. Without the transformer it would also take an MM cartridge. I wonder what Tim de Paravicini meant when he claimed it's a "terrible" design in discussions with designer SY?? Tim and I have had some great discussions in the past, especially about component quality. As an engineer Tim is happy with whatever measures the best and only uses tubes for commercial reasons.
AMR-iFi R&D
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Post by michaelw on Jul 5, 2019 19:45:07 GMT 12
sidebar - the sp11 was superb but unobtainium, sp9 was just blah, the sp14 was the hybrid sweet spot despite being 99% SS 
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Post by Owen Y on Jul 5, 2019 20:17:14 GMT 12
For a while, I had an ARC SP-14 residing with a neighbour 2 doors away (together with an ARC Classic 60) - the SP-14 was very 'white' (as HP used to say), almost unlistenable to ny humble ears.
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Post by colinf on Jul 5, 2019 20:30:15 GMT 12
So you thought you'd 'loan' it to your neighbour... Hmm, where does it say again in the bible about love thy neighbour?š
AMR-iFi R&D
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Post by jon on Jul 5, 2019 20:41:13 GMT 12
The HMN phono looks good. Without the transformer it would also take an MM cartridge. I wonder what Tim de Paravicini meant when he claimed it's a "terrible" design in discussions with designer SY?? Tim and I have had some great discussions in the past, especially about component quality. As an engineer Tim is happy with whatever measures the best and only uses tubes for commercial reasons. SY does say he appreciated Tim's feedback.
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Post by Owen Y on Jul 5, 2019 21:37:31 GMT 12
jon - Iād like to see/know more about your HMN. A new thread?
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Post by jon on Jul 6, 2019 10:45:00 GMT 12
Hi Owen
I bought it from David, some time ago. Did not build it. It's been fantastic and I recently re-tubed it. That's its story
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Post by michaelw on Jul 6, 2019 12:50:42 GMT 12
For a while, I had an ARC SP-14 residing with a neighbour 2 doors away (together with an ARC Classic 60) - the SP-14 was very 'white' (as HP used to say), almost unlistenable to ny humble ears.
i found the original hp tas review 
to paraphrase...
he said the sp14 was idiosyncratic, not particularly accurate but musical. excellent bass. resolution as good as the best. wide soundstaging but no layered depth.
but there is an extra sparkle in the 4-8khz band that can turn into blinding sun.
i also listened with the classic 60 into shahinians and maggies. the whiteness of the all arc combo didn't bother me and was largely absent when used with the quicksilver mono amps.
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Post by Owen Y on Jul 6, 2019 15:31:14 GMT 12
So you thought you'd 'loan' it to your neighbour... Hmm, where does it say again in the bible about love thy neighbour?š Sorry, my poor writing - I meant, my neighbour residing 2 doors away had this ARC combo. michaelw - the SP-14 had no appeal to me at all, artificial sounding. I really wanted to like the Classic 60, given all the great press, but it sounded 'grainy' & 'un-relaxed' to me, not my cuppa. Maybe all that sand (silicon) in there, impairs the vacuum
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Post by Owen Y on Jul 6, 2019 15:33:41 GMT 12
Hi Owen I bought it from David, some time ago. Did not build it. It's been fantastic and I recently re-tubed it. That's its story Which David...? Is the specs of the HMN published anywhere? eg. Gain, sensitivity, etc.
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