Btw, @intactaudio : you capacitance parameter of 80pf coukld be not real to make SUT measurements as the 300k load.
Normally what sees the MM stage + SUT is a load of 47k and capacitance around 200pf. Then measures arwe different that with your " choosed " parameters.
Unfortuntaelly cable manafucterer almost never gives the cable capacitance but almost all are higher than 150pf and even over 200pf.
I think everyone who prominently recommends SUTs on this forum also cautions to select low-capacitance cables. There are ample phono-targeted ICs optimized for low capacitance. Select one of those models, keep the run short (ideally under 1m), and hitting a capacitance under 80 pF is quite easy.
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Here’s my current assessment, which has been nicely summarized by @intactaudio : basically, the cartridge is naturally developed as a current generator,
I was pretty convinced of ^that^ myself, but I still have some lingering confusion.
however for the past decades, phono stages were created to unnaturally transform the cartridge into a voltage generator by adding the load in the phono stage.
Unnatural is a bit subjective. If one shoves the current across a resistor then they can measure the voltage across the load like ohms law states. Ohms law seems like it is “natural”.
However, when the cartridge operates as a current generator, no external arbitrary loading needs to be added to the signal created by the cartridge. So, it seems, based on my limited knowledge, that the current based phono stages would be most naturally associated with phono cartridges.
Many people use the Sutherland, and other trans -impedance phono stages, and love them. Usually with carts that have a very low output impedance.
And they do have an allure.
And many phono stages use a voltage based design, and/or SUTs and love them.
I was leaning heavily towards the Sutherland, but got a phono stage with SUTs built in, mostly because I liked the look of it, and it had two inputs.
if we look at a step up transformer, with an input to output ratio of 1:2, then we see that the voltage is doubles, and the current is halved.
If it is 1:20 then the voltage is x20 and the current 1/20.
A cart does not look too dissimilar as the input winding is serviced by the magnetic field of the magnet. The magnetic flux varies with the cantilever movement.
The output winding is the coil.
- When there is a lot of windings, like on a MM, we get more voltage and less current. (Probably better for a voltage based amplification.)
- When there are fewer windings we get less voltage and more current. (Maybe it is better for a current based amplification?)
- Then there is a middle ground with a bit higher output voltage or with a higher output impedance were it seem like it is unclear and all bets are off.
^This^ is not much of an answer, other than the choice of phono stage sort of relies on a cartridge in front of it.
And in this case we sort of need to “put the cart before the horse”.
Or…
We already have the selected phono stage, and we damned well better select a cart that will work with it.
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In other cases, there are individuals who already have the selected Cart'.
In some cases, there is more than on Cart' in the collection of desirable models. Again, in some cases, the users of the Cart/Cart's are expectant that their Phono Signal Path is optimised for the Cart'/Cart's to present at their best.
To assist with my experiencing a Cart' used in various operating conditions, I have a Phon' with a Very Good Quality Bult in MC Stage, that allows the Cart' to be used in multiple configurations in relation to Input Capacitance, L+R Channel Gain, Input Impedance. This device pretty much allows for a Cart' to be used, whilst subjected to a reasonable number of operational parameters.
This same Phon' is a loaner Phon' and has been used with Ortofon's up to Windfeld Level, Miyajima and an AN IO.
The Phon' is not a lacking in SQ device, it is quite impressive, it has been used as a loaner in other systems for lengthy periods of time.
With a Head Amp attached to the MM Stage in my system, it has presented certain types of music with a Jaw Droppingly good account of itself.
In comparison to other Phon's using a SUT, it does not Wed to the SUT used, in a way that is as notable for the impression being made as with another Phon' > SUT in use
All the Cart' owners of the ones listed above have their own Designs for the Phono Signal Path, and each have their own unique configuration for the Phon' > SUT or Phon' > Head Amp. A Phon' with a Built-In dedicated MC Stage is welcome but not the preferred end game device.
The outcome being referred to, is one sharing similarities with the one that is seemingly the most prevailing within this Thread.
It does look like the difficulties with reconciling the math for the electronics and the rabbit hole leading to oblivion, commonly referred to about using SUT's only causes concern to those who want to Cudgel and Beat the methodology of the signal path being produced with a Technical Challenge.
The other side of the fence on lookers, especially those who have adopted the method of using a SUT or Head Amp, are using the reports made, looking to be quite pleased with the at hand option, to have a simple to use device, that is quite effective at offering methods to fine tune a particular presentation via a SUT or Head Amp, that is producing a presentation that has an attraction.
It is this, that is certainly one the motivators to avoid the usage of a device that is with limitations in how it can be configured, especially the type of limitation that is on offer from a dedicated MC Stage as the only option to be used.
The attraction to the method of using at hand options for working with electrical interfaces within the Phono Signal Path, is as satisfying as the ones used by myself for working with the Mechanical Interfaces required to produce a much improved environment for the LP Album to function in and the efforts made to use a Vinyl Material that is as purified from contaminant when in use as I can achieve.
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… , L+R Channel Gain,…
@pindac is a gain imbalance common in cartridges?
(I have a cart with some channel imbalance, hence the question.)
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I am not educated enough to answer your question, these are the types of question I would take direct to my Third Party Cartridge Service I depend on.
Third Party Cartridge Services from what I have discovered through investigation and discussion with the Technicians does suggest there is a Channel Imbalance being checked and corrected as part of the Serice on offer.
There are Third Party Services who are happy to show evidence of their work, and some will put out photos of the Readings that are being achieved as part of the refurbishment work.
My reasoning for the purchasing a Phonostage with a L+R Channel Gain Control, is to do with my totally trusting the Designer /Engineer and accepting the options incorporated into the device to deliver as per the designer's intent.
Additionally, as I am usually working with Dual Mono Volume Controls in the Pre- Amp's used and will one day soon have a my New Design Balanced / Single Ended Pre-Amp' Built, to be used with the Modified Power Amp's, which will have a Balanced / Single Ended Input, the option to tweak a loading on a Channel was to me a worthwhile tool, as the conversion to a Balanced Signal Path as the additional option has been projected for a very long time.
I am avoiding the subject of Phon's and Balanced Signal Paths at present.
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Anyone who have tried a SUT with the Aesthetix Io?
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@rauliruegas
Btw, @intactaudio : you capacitance parameter of 80pf coukld be not real to make SUT measurements as the 300k load.
as stated in the text you pulled the above numbers from, those are the actual values of the referenced phono stage cable combo not some "made up numbers"
Normally what sees the MM stage + SUT is a load of 47k and capacitance around 200pf. Then measures arwe different that with your " choosed " parameters.
Again this is covered in the text referenced by @antinn on the first page. It is indeed true that 47kΩ || 200pf may be a typical number, it simply represents a situation that has a good chance of being less than ideal for use with a SUT. Gaining a fundamental understanding of the tradeoffs of the cart /SUT/phono interface goes a long way in furthering the trend of commonly occurring mistakes that historically has given SUT usage a bad rap.
Unfortuntaelly cable manafucterer almost never gives the cable capacitance but almost all are higher than 150pf and even over 200pf.
then you need a basic understanding on how load capacitance adversely effects a SUT and you also need to find a new cable manufacturer.
dave
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To the notion that cartridges are “natural” current generators I would say that the general statement can only be applied to LOMC cartridges with very low internal R in relation to V output. I would also note that in a “trans impedance” stage , the first stage converts current to voltage. Thereafter and in the RIAA filter, the signal is handled as a voltage exactly as in a conventional phono stage.
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In a earlier post within this thread, I made it known, I had not given too much attention to using a shortest length cable between SUT and Phon'.
As said in the earlier post, I use a cable of approx' 70cm (28 inches)
My memory got Jogged and I recollected a few things previously learnt.
The Capacitance for the Cable I use is 57pf per metre using Manufacturer Spec.
A friend, prior to my acquiring the 70cm Cable measured an identical cable with different RCA's in a 1.2mtr length at 90pf (Memory Jog Moment).
Maybe I was focused on creating a improved Capacitance art the Interface and purchased the 70cm length to attempt to achieve this.
Ihave detected minimal differences between the Two Cable lengths in use, but this attributed mainly to the Cable RCA's.
I would like to think that a 70cm Cable, even with a different RCA Plug is near optimised with the required 'pf' at the interface.
I hope this assists with adding a little extra support for the usage descriptions given with the owned and in use SUT's and the occasionally introduced Head Amp.
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Dearb @intactaudio : Thank's. I know all those and certainly about capacitance but my post was because the measures in the vinatge SUT's was not with 300k-500k and I found out measured at 47k and 180pf.
That's all.
@mulveling , yes shorter cable is better but normally audiophiles use 1m. because is the " rule " by cable manufacturers and in the other side many times the owners need that 1m. for its system SUT place/phono stage.
R.
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Also, in a voltage driven conventional stage, the input load R can be thought of as the simplest form of passive current to voltage converter.
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Dear @holmz : "" The voltage input design produced has very precise gain, extremely precise RIAA compliance and unmeasurably low distortion. ""
That is the critical and must important issue/characteristic for me about current/voltage subject.
That statement is not only " imagination " of Palmer but he took the comparison measures and as always he did it in REAL TIME thank's that he have several of the computer AD modeling/simulation along the ones he developed and I know he did that kind of job and statement because in a very hot discussion here ( 3-4 years ago ) he showed inmediatly the measurements, one after the other.
Audiophiles can like whatever they like but with UNMEASURABLE low distortions: who cares about, ceratinly not me.
R.
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@intactaudio : Technics THD is 0.001% and noise level below -95db.
.
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"Assuming an appropriately / ideally matched SUT and MC, What are the inherent advantages or disadvantages of inserting a SUT after the MC in the audio chain? Does the SUT theoretically enhance or degrade the sound quality? What does the SUT actually do to the sound quality"?
It does seem from the descriptions supplied from certain individuals who have taken the time to check for an appropriately / ideally matched SUT > MC, set up as an optimised interface, that there are attractive presentations that can be discovered, and in comparisons, to other interfaces using a different SUT or Cart', that are again an appropriately / ideally matched SUT > Cart', that there are discoveries made that are not so attractive.
Being Wed to one type of Phonostage and its MC Input will not allow for the discovery to be made, that the Cart' in use is able to present in manner that has increased appeal and attraction.
Through using a method that restricts the experiences to be had with the Cart', where it is to be used with limitations to the interfaces that can be produced, is an OK method, but certainly a method not embraced by all.
To add ancillaries to work in conjunction with a Cart' and Phon', the method when chosen can prove be quite valuable as well as limiting, the experimentation required to discover the ideal interface and optimisation is a process and requires time to finalise the ideal set up.
Again, as a method it is OK and not embraced by all. Where it has merit, is that the permutations that can be put in place are certainly expansive in the introducing of new discoveries of how the Cart' can present.
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Dear @o_holter : I think your PS is high gain active unit then why a SUT?
R.
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@lewm
I was about to ask details about the transimpedance phono stages, such as exactly how the current is converted to voltage, and where / if a load is added, and how it automatically detects how to do the voltage conversion, but maybe that's a college course, so I decided to do a simple google search, and found this seemingly very informative video reviewing the advantages of the current mode phono stages, which apparently is getting a better signal to noise ratio, amongst other things. . . and he does recommend a cartridge with an internal impedance under 10 ohms, but maybe he doesn't know everything. . .
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yet another very dogmatic thread, this. If SUTs are evil, why do designers like Ortofon, Yamamoto, shindo et al use them rather than active circuits? Surely there are many ways to Rome and implementation matters.
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@drbond
Basically a voltage amplifier will deliver voltage gain with whatever current is required to do the job.
Hence in a power amp, sometimes there is not enough current to maintain the voltage at the speaker
If there is not much voltage, but a bit of current then a current amplifier can be a good solution.
A current amplifier can later push that current across a resistor to compare the voltage… and drive a voltage amplifier in an output stage or RIAA circuit.
I think I mentioned earlier that this is using “the natural” ohms law.
and, in fact, the cartridge itself can push try and push the current across a resistor and use compare the voltage with a voltage amplifier.
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The OP made it known that they are inquiring about a Specific usage of Ancillaries used in conjunction with a Cartridge and Phono-Pre-Amp'.
They made it known there were limits to their knowledge on the subject.
I can only assume the request to offer a description of whether a SQ is Improved or Degraded through the methodology is to be attained from a Subjective Evaluation and reports being offered from individuals who are familiar with methodology.
Receiving feedback from others who were or had optimised this method and who could offer a extended description as a result of the various permutations that can be produced will have shown, that certain permutations don't work for some and are rejected.
SUT's are usually met with the alternative being the Head Amp, and informing the OP of this as an option is an off-route diversion from the initial inquiry, but does have relevance.
Another Older Thread has resurfaced with the SUT as the main Topic, and this will have proved to be an excellent read for the OP if they have visited the Thread.
I hope the OP has been able to keep their eye on the prize and not get to bogged down in the noise that has been Trebuchet Launched into the discussion in an attempt to Siege the Castle.
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Well done @pindac A trebuchet both looks, and acts, a lot like a tone arm.
(Or at least a tone that is not a great match to a cart.)
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Seeing as it has a Rock Mounted at its furthest point of Cantilever, it is only really lacking a Bearing Assembly at the Anchoring Base.
Can one imagine the end of the days siege, when the oppositions meet down at the local Tavern. The Groups are slurping away and making bold claims about the who had the better day and end up having a bit of banter and head of to fight another day.
Remaining in the Corner is a member from an opposition, who is not so usual a type, who has intruded on a couple who are nothing to do with the conflict, and who were having a romantic moment.
The 'not so usual type' has entrapped the couple, so they could not vacate. Where throughout the whole evening the couple have been exposed quite unwanted, to the 'not so usual type' incessantly going on about why their sides Trebuchet is better than the others. Where the designs are being drawn on Flagstones to show where theories are 'so called' proof of a design superiority.
That poor couple, I really feel for them when bombarded with such drivel from a very narrow minded, obsessive, 'not so usual type of individual'.
Jumping forward a few Centuries, I'm glad that as diplomacy evolved, the Trebuchet developed into a Device for extracting embedded recorded data from a Disc.
The Heat of the Battlefield is still quite prevalent, in the P***ing Matchs, that are regularly encountered, where the endless drivel is constantly resurfacing and spieled out "My Twentieth Century version of a Trebuchet is better than Yours"
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Dear rauliregas
You ask "I think your PS is high gain active unit then why a SUT?"
Indeed. "Active" is just the beginning, regarding the Aesthetix Io, you could add dynamic, explosive when needed, and especially, pure. Pure tube sound all the way. If you like that kind of sound (I suggest we don't take that debate here).
There is only one caveat. You need a quite strong output cartridge. My Lyra Atlas works fine at 0.56 mV. If it goes lower, like below 0.30. e g the single layer low output version of the Atlas - you can most probably still get good sound, but there is a tube challenge. The four tubes in the uber-sensitive first gain stage of the Io need to be ULTRA QUIET. Not just ordinary good quiet. If not, you will get background tube noise. Maybe you don't hear much of it when playing music, but I don't like it anyway. AND if you like to feed the Io with the best tubes, you want the very best NOS in that position. And these can be hard to find, now.
I tested a SUT with the Io and did not like it - sounded good at first but then I noted that it subtracted from the purity, the sound became more hi-fi, for lack of a better word. But that was with a mid level SUT years ago and things could be different now.
I am happy with my Lyra Atlas, I think the synnergy with the Io is good, but it may be that I would have liked the low output version (Atlas SL) even more - with a SUT in between, to help it along. It seems that low output MCs is the main new direction of cart development, now.
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@o_holter Whilst there is an inquisitiveness to discover if there is more to be offered from the Cart' when used in different permutations with additional ancillaries, your first experience has served to support some of the experiences reported on here, that there are Ancillaries that can be a little underwhelming once experienced within the home system.
There are ancillaries that can be used that are quite capable of taking up the position permanently and supersede the use of a Dedicated MC Staged.
The ideal outcome might be an ancillary is discovered that is very attractive to yourself and one that extends your enjoyment of your Cart' allowing for two different approaches to how it presents with an equally good impression being made through the use of each configuration.
As said, previously within this Thread, I have had experiences with a Head Amp > owned Phon', that has been Jaw Droppingly Good for certain Types of Music, but the Head Amp has proved, to be a little difficult to recreate this on the other owned Phon'. The SUT's work better for me with this both owned Phon's and when one Phon' has been out on loan, the users of it have opted for the Phon' to be used with a SUT or Head Amp in place of the dedicated MC Stage.
The SUT's work with the colouration of Valves to various influences, richness and a Loose Low Frequency can be perceived as increased, through to, Transparency is seemingly being presented with a Tight Lean Low Frequency and accentuated Mid's and High Frequencies are seemingly projected.
My experience of the Head Amp has been to perceive the presentation as quite Transparent, much increased over the SUT's that can create this perception. The Bass Depth available from certain designs of Head Amp can be visceral on the body and way beyond what one might have expected.
As a suggestion I would encourage a range of SUT's and Head Amp's to be tried, as you have a Dedicated MC Stage there is no rush, but the new experiences are enjoyable and in general are very easy to be put in place, hence the Jaw Dropping experience.
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@o_holter
I tested a SUT with the Io and did not like it - sounded good at first but then I noted that it subtracted from the purity, the sound became more hi-fi, for lack of a better word. But that was with a mid level SUT years ago and things could be different now.
When you delve into the waters of the external SUT there are a lot of considerations beyond the obvious. One "gotcha" many people run into is dynamically overloading the input of the phono. It is important to remember that the numbers thrown about for phono are all typically referenced to 5cm/sec @ 1kHz so your atlas will put out 0.56mV @ 1kHz with a 5cm/sec signal. The important thing to remember is that the same signal level @ 8kHz will be 12dB hotter for a 2.24mV level (20cm/sec). Now toss in a bit of cushion in the form of a 12dB of headroom and you might see a nearly 9mV dynamic peak from that cart. Now consider what happens when you put this 0.56mV signal into a 1:20 SUT and the nominal 1kHz level is in the 10mV range and the dynamic HF peaks are in the 160mV range. That 160mV @ ~8kHz will pretty much momentarily eat the input of any phono for lunch. The good news is this is just a quick transient overload so it isn't a constant nagging problem but one that only pops up occasionally. The bad news is since this overload happens dynamically it is elusive and by the time your brain senses something is amiss, it is gone.
Now back to the situation where you move to the Atlas Lambda which basically cuts the output in 1/2. If you add anything more than a 1:2 SUT you have to dig a little deeper into the available overload margin to make sure you don't start tickling the HF input limit with your peaks. This overload situation happens in the very first stage so any gain adjustment beyond bypassing an active stage entirely does not change the situation. Just because a switch allows you to get 12dB less gain doesn't also mean you now have 12dB more input headroom. With the current trend of higher output cartridges like the Atlas being paired with the typical 1:20+ SUT intended for LOMC's I see this type dynamic overload happening al lot.
A good example of this is comparing an EMT TSD15 (24Ω 1mV) to a denon 103 (40Ω 0.3mV) From an impedance standpoint the same SUT can handle either but if you use the typical 1:20 on the 103 you end up at the 5mV "traditional" MM spec. but use that same 1:20 with the EMT and you end up with a hot mess because the phono stage input is not happy with the quarter of a volt peaks it is being fed. This results in a situation where the denon owner loves his SUT and the EMT owner curses the same device. Drop the ratio of the SUT for the EMT to 1:7 and more often than not you will have a happy camper.
dave
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Hi @intactaudio ,
I have a DIY phonostage based on EAR 834p schematic + EMT TSD 15 + SUT Sun Audio SAT1000 Tamura.
https://www2.big.or.jp/~sunaudio/assem/sat1000_e.html
I use 20 Ohm input (26dB, 1:20). The phonostage has overload points - (1% THD+N) for the 834P were 69.2mV at 1kHz, 260mV at 20kHz, and 7.85mV
I tried 40 Ohm input. But it sounds less good, thinner and less musical.
Before this I used Altec 4722 SUT with Ortofon Jubilee cartage. But I don’t like this SUT with EMT TSD 15.
I tried a modern Houfe T890 SUT and Jensen JT44 SUT. But both are very low resolution and dynamic compared to Altec. I also had Tamura SUT-83TWIN. Bot Tamura transformers are the best.
Alex.
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The EAR 834p is a Phonostage I have been encountering for many years.
I have been demonstrated it when it was first released and was listening to it in use on system using other EAR Amplification in the late 90's on regular occasion.
At various events and Bake Off's I have attended throughout the past 10 years the Model has been demonstrated in both Original Build and the Clone DIY Version.
The Phon' in my assessment has a very noticeable richness and bloom at the lowest frequencies.
I find it hard to think of any SUT that will reduce this presentation to a condition where it is difficult to detect. From experiences encountered, a Head Amp' might be the most successful in reducing the perception of richness.
A better description of what was wrong with the SQ for your tastes, that encouraged the changes of a SUT, might help with understanding what your ideal presentation could sound like.
When my Bespoke Built Phon' was being built and I was experiencing it at different stages of Design, Topology and Circuitry, I rejected the prototype on more than one occasion, due to the detectable Richness and Bass Bloom that was being perceived. It took a careful organisation of the Topology and Circuit to use Boutique Cap's and Resistors, that were selected through component rolling to tame the ECC 83's. I use this with SUT's or occasionally a Head Amp with Ortofon Cart's.
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The point I was trying to make when I pointed out that transimpedance phono stages generally are just voltage driven stages with a current to voltage converter added on to the front end is that they are subject to foibles just like voltage input phono stages. As Atmasphere pointed out in another thread, a current driven stage ought theoretically to present zero input impedance, but that is impossible as there would then be no signal at the output of the converter. So they all have a finite input impedance ranging from ~2 to ~20 ohms, based only on research I’ve done on my own. That’s a fly in the ointment of perfection. Because of differences in actual input impedance ( and probably in current gain and maybe distortion of the input devices, either an op amp or transistors), different transimpedance stages seem to act differently and sound a bit different dependent upon the internal R of the cartridge. This is evident to me based on my communication with Mijostyn. He uses a Lino and I use a BMC MCCI. And each of us has experimented with a few different LOMCs. We’ve reported somewhat different results, depending on cartridge. So there’s nothing perfect about current drive or stages that use it, though they can be very competitive with the best voltage driven stage.
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@alexberger
I use 20 Ohm input (26dB, 1:20). The phonostage has overload points - (1% THD+N) for the 834P were 69.2mV at 1kHz, 260mV at 20kHz, and 7.85mV
you seem to have a frequency number missing from the above since you have three voltages listed and only two frequencies.
dave
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Dear @alexberger : Tamura are if not the best out transformers one of the best out there.
Now, you are just fine with those 26db of gain and if you want improve that SUT then take off all those impedance swiths and let direct solder to the one with your EMT.
R.
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Dear @lewm : can be very competitive with the best voltage driven stage. "
Why do you think that Palmer choosed voltage instead current design?
R.
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@intactaudio
One "gotcha" many people run into is dynamically overloading the input of the phono.
With the current trend of higher output cartridges like the Atlas being paired with the typical 1:20+ SUT intended for LOMC's I see this type dynamic overload happening al lot.
This in my view is more important than loading. most vintage transformers have too much gain for todays phono stages. - especially solid state phono stages where high frequency overload margins can be much lower.
During the covid lockdowns I pulled out all my transformers and ran a series of tests with several cartridges ranging from 3-40 ohms internal impedance with each of the transformers.
The testing confirmed for me -
- Most important is getting the gain structure right for the cartridge and phono. This has more impact on the sound quality than the load the cartridge sees ( assuming the load is reasonable ).
- Each of the transformers had sound characteristics that were easily discernible regardless of what the cartridge internal impedance was.
- The actual load that the cartridge sees is less important than the gain structure and interface between the transformer and phono.
- I do not like any additional loading ( primary or secondary ) on the transformer.
- Cable has a massive impact on sound quality and characteristics.
On a couple of the transformers I was able to reconfigure for a range of gain structures - in each of these instances I preferred the lowest gain setting required to get the phono operating at about 1/3 volume setting. Phono used was a tube phono with 42db gain.
One oddity was that I preferred the cheaper Altec 4722 to the higher spec Altec 4629 on a Denon 103, but this was the one exception - with my other 40 ohm cartridges the 4629's were better.
As an aside one of several SUT's I have is a pair of Altec/Peerless 4629's ( same as 4665 ). Have you ever tested these comparing the Altec 4629/4665 transformers loaded at 47k vs 70/80k as designed ?
The other question I have is the input capacitance of tube phonos - most of which will have 150-200pf - have you found whether this adversely affects the transformers ?
Lastly fyi with a pair of top of the line Jensens which have been designed to be used with a recommended zobel network I have experimented with scoping the load ( using the cartridge resistance as a load ) and tweaking the zobel network for each cartridge - this was beneficial - the improvements were quite audible,
Overall the current sensing step up ( a custom bespoke design from a cartridge manufacturer/designer ) that I have ( into the same 42db tube phono ) outperforms all of the transformers in bass extension, midrange information and transparency regardless of internal impedance - my current sensing unit works with 3 - 40 ohm cartridges no problems, but I have experienced variable results with some of the commercially available units such as the ESE Labs Nibiru and BMC.
One interesting trait is that with the SUT's I can spend hours dialling in the VTA, and still be unsure, whereas if I plug the current sensing unit in VTA is a doddle, the optimum is clearly audible - and then if I plug the SUT back in voila. The transparency of the current sensing unit used in conjunction with a tube phono I have is thus far unassailable - including some other highly regarded phono's such as Klyne System 7/Jadis etc that I have owned.
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Raul, with regard to your question above, who is “Palmer”? Anyway I hope I conveyed my opinion that current driven phono stages are not categorically better than voltage driven ones. They’re just a novel approach to an old problem. Again, in my opinion.
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One Treatment that is not suggested within this thread, is the use of a Degauss Device on a LOMC or SUT.
During the demonstrations carried out of SUT vs Head Amp vs Dedicated Built-In MC stages, when the Degauss Device is used, there is a notable audible improvement to the presentation when compared to the presentation that has not been degaussed. In very few cases the difference in the presentation is almost perceivable to the point it is seeming that a new Cart' is in use.
@dover Current Sensing Unit? - Can there be a more expansive description, I am all ears. Bespoke Built is even more of an appeal.
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@pindac
You do realise that everything can be demagnetised , including the phono, preamp stages and power amps - all with subtle gains.
If you are going down that road, to the nth degree, - have you checked all your electronics for polarity ( relative to the incoming mains ) in order to minimise DC leakage. Just to make it really interesting, here in New Zealand each alternate power pole has reversed polarity - but the problem is that if there is a power outage or adverse event, the polarity can reverse. So the tests must be done after each power outage or indeed if you move house.
I don't have any detailed knowledge on the current sensing unit. I cant tell you anything about the circuit.
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I would assume that many things can be demagnetised, the reasoning for demagnetising would be the more difficult reason to comprehend.
I am happy to leave the Math to those that fully understand it through creating the equations and not just merely quoting it.
The Clever Types can produce devices that cut to the quick and do what they say on the Tin.
A Degauss Device is quite affordable in some cases cheaper than a Device to control Anti-Static on a Vinyl Album and is especially cheaper than some of the SUT's and Head Amp's that can be purchased.
I have heard the positive outcome of a Degauss being administered and as stated in some cases the improvement heard has been quite notable and definitely worthwhile.
It really does not make sense to have multiple Thousands of £'s invested and not give the full electronic support to the critical devices used in the Phono Signal Path. It is not uncommon to see a Phon' Pre- Amp' set up costing close to £/$ 5K, to be used with Cart's costing upward of £/$ 2.5K.
A mechanical device to support the Cart' and serve as a conduit for a Signal Path can quite easily be seen as a cheap option at £/$ 4K.
Spending £/$ 200ish on a Degauss Device does not seem to be the purchase that is a ninth-degree approach.
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What Dover posted above about proper gain structure being the main objective is shared by quite a few experts. A good long explanation of why loading, of either the primary side or secondary side is not very important, but, preventing overloading of the phonostage by selecting the proper gain IS important is described in a "white paper" posted on the Rothwell site:
http://www.rothwellaudioproducts.co.uk/html/mc_step-up_transformers_explai.html
I believe others, like Jonathan Carr of Lyra, believe in utilizing very little loading (i.e., HIGH value loading resistor or no added resistor) unless the phonostage is prone to overloading from the ultrasonic peak of the cartridge or RFI breaks through.
I utilize a tube phono stage that is not prone to ultrasonic overloading, and I agree that very little loading usually works the best. My phono stage has a built in SUT, so I cannot fool around with gain, but, I do know that gain is a bit low for my particular cartridge (Transfiguration Orpheus L), but, given that I have zero noise breakthrough, I don't worry about cranking the volume up a little bit to compensate.
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@rauliruegas
You say that "the best SUT is no SUT at all." What structure(s) in your ideal phono stage replaces the gain that the SUT provides, and how is that necessarily better than an SUT?
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Dear @drbond : In my first post in this thread I gave you the answers.
You are using the CH unit, please ask your self: WHY?
R.
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@rauliruegas
In that post that you refer to, you mention:
"A SUT is not a passive device because any audio signal passing trhough those transformers makes that the " hundreds " of meters on each transformer react to that signal and starts the degradation and you have to think that the signal has a " long trip " inside each transformer wires and at each mm. the audio signal is degrading by that SUT.
In the other side a good SS active high gain design say ith bipolar active devices the signal must pass only trhough a matched pair of transistors in that first critical gain stage and degradation is at minimum way lower that in a SUT."
However, a signal in a SUT doesn't pass through meters of wire, nor does it necessarily have more degradation than transistors. . .unless you can point me to scientific papers. . .
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Dear @drbond : The signal in a SUT pass through the primary windings and the by induction runs in the secondary windings. This proccess means degradation levels. Now, if signal does not pass through " meters of wire " as you said then why with the same SUT overall characteristics an EMIA cooper SUT " sounds " different " than a silver wired or why a silver crossover inductor sounds different than the same unit/same manufacturer cooper inductor.
Along all what happens inside a SUT: what does the cartridge signal passthrough in your CH with an additional SUT?
signal must goes through the SUT female input connectors and solder joints along the IC cable and the cable male connectors and solder joints. Same proccess to the other side/output of the SUT.
In an active high gain unit instead all those kind of tourtose paths signal need a pair of bipolar devices. I could think that your CH is a good design with no RFI problems down there and with wide bandwindth and high overload margin.
I think that you are trying to justify your self a SUT in your system that makes no sense to me but always is an alternative. Just try it, no problem for any one and in this way you could learn something about or confirm what you already know.
You do not need " scientific papers " because no one that I know already makes in real time simulations with both kind of designs to look any kind of measurements you can have in mind.
Banwindth limitation in a SUT is a disadvanatge vs active designs and this you can attest when you paired your CH with a SUT through test listening sessions with the same LP tracks, is so obviously that only a " deaf " man can’t distinguish in between but you have to experience it.
Remember that my target is to stay truer to the recording, I don’t know wich your targets and I don’t care really because is you who are asking and needs to live that experience.
I posted here that my special modified Denon /Murata SUT in my phonolinepreamp, where the dedicated dual mono MM is nothing but a first rate design, performs really good but a " little " short to the active high gain dedicated dual mono MC bipolar stage.
R.
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The Coil on the Cartridge > Cartridge Connections > Internal Wand Wire > Pillar Connections > RCA Phono Cable and Connectors are all able to have an impact on how the Signal is sent and the SQ of the Signal is to be perceived.
A Dedicated MC Stage is one that in many cases, might not be able to compensate for upstream influences on the signal and create a presentation that has an attraction that is on parity with the attraction that can be created, using separate ancillaries that can have an influence that compensates for upstream influences on the signal path.
There is no doubt that the option to influence the SQ and presentation with the use of an ancillary that bypasses a use of a Dedicated MC Stage and creates a MC Stage through adapting a MM Input to take on the role of a MC Stage, is one that has won over many adopters of this as their chosen method.
The Math behind the differing options is only one part of the equation.
The interface chosen and the impact it has on the end listener is substantially more important, as this is where the satisfaction in enjoyment of the Vinyl chain is to be found. It is hard to convince most that the Math should be their end goal behind their choices made.
Trusting in Designers and their Skills to produce a Device that is a correct interface as an inclusion in a Circuit and Signal Path, is the most typical and successful route to finding the methodology that offers the most attraction.
@dover is testament to this, his route to have an ancillary that satisfies has ben realised through his trust in his EE and their design for a Bespoke device.
I'm glad it is revealed as I am keen to learn more and will approach the subject with my most trusted EE Designer, to see what I can learn about the concept.
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Hi @intactaudio ,
Finally, the overload points (1% THD+N) for the 834P were 69.2mV at 1kHz, 260mV at 20kHz, and 7.85mV at 20Hz.
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Hi @pindac ,
I had the original EAR 834. I like it but I saw it was built with very cheap components and power supply. Romy The Cat article "End Of Live Phonostage" inspired me to build my DIY EAR 834 with better parts (including air capacitors, z-foil and AN silver Tantalum resistors, Jupiter signal capacitors,...) and power supply with LCLC filtering, parallel voltage regulator based on 0A2 tubes and different other upgrades.
So, my DIY EAR 834 is a different animal compared to the original one. The schematics is very important but the implementation is even more.
Regards,
Alex.
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Hi @rauliruegas ,
Yes I use these Tamura SUT with box build by myself without switches. All wires are directly soldered to RCA.
But I thinking to built a new box for my DIY phonostage where I want to place SUTs near input tubes. So I can rid of SUT to phonostage interconnects.
Regards,
Alex.
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@drbond : What happens with an external SUT about all those additional " steps " where the cartridge signal must pass through is almost the same when the cartridge signal from your CH must goes to an external line preamp and that additional step makes nothing but signal degradation but exist something additional in your electronics and is that the cartridge signal suddenly must pass through a way different line preamp design not a CH unit to preserve at least same " signature ".
That's why normally is better to own a Phonolinepreamp where we have to add nothing to the cartridge signal.
R.
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@alexberger I have no criticism of the 834P (Original) and in (Clone Build Versions) I would say a few Clone Versions were built to a high spec' as I know one of the builders and who they take their influences from on DIY Projects.
As said the ECC83 is a hard Tube to tame and can be overbearingly rich and bloat the lowest frequencies.
I learnt this more than 25 Years ago with a Valve Pre-Amp'.
I also learnt I am repellent to discernible Rich Tones and Loose Bass.
There are humungous music enthusiasts who are very satisfied with this type of presentation, and I am genuinely very pleased they have discovered the Sound Quality that offers satisfaction.
The SUT as already referred to within this thread is capable of adding richness and in some cases with a quite discernible and notable impact on the SQ.
As said, it is difficult to imagine a SUT in use with an EAR 834P that would be capable of reducing the perception of richness, the pairing would seemingly create a richness, but to what degree of being noticeable, and perceived as an attraction or repellent is with an unknown outcome.
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@rauliruegas
Thanks for the detailed response. So, just to clarify, you are most concerned about the bandwidth limitations in a SUT. I could agree with that; however, I'm not certain that actual signal degradation is any better or worse in a transistor, just different.
I think this video from Veritasium does a rather informative job of explaining how current actually travels: no it doesn't travel in the wires but in the surrounding electromagnetic fields, and electrons don't "flow" in the wires, either in AC or DC, and in a wire with no resistance, the current flow is instantaneous, whether 0.001 m long or 100,000 m long. I suppose the magnetic properties of the silver and copper account for the difference in sound, and while I really don't know all the details, I don't know that the method by which a signal is transmitted in a transistor is any better than a transformer.
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