ifi Zen Phono Review (phono stage)

[anmpr1]

Removable headshell. Compared to single piece arm like for example the Rega 250/300 etc.

Thor

10-4

 

[thyristor]

Removable headshell. Compared to single piece arm like for example the Rega 250/300 etc.

Thor

That's just a common audiophile myth.

 

[mike70]

Korf debunked that myth with measurements on headshells ... a Jelco HS-25 was better than Rega RB300 tonearm headshell.

SME uses removable headshells ... i doubt SME do crappy stuff
All that bad marketing from certain manufacturers to sell more, is just hilarious ... as what they said against the Technics direct drive ... come on.

 

[Thorsten Loesch]

That's just a common audiophile myth.

Alas, it is not. We are dealing with resonant mechanical systems here.

Thor

 

[Thorsten Loesch]

Korf debunked that myth with measurements on headshells ... a Jelco HS-25 was better than Rega tonearm headshell.

I did not suggest rigid arms were better. I suggested that for the DL-103 a rigid arm is a poor match.

SME uses removable headshells ... i doubt SME do crappy stuff

I wrote nothing about removable headshell's being bad.

All that bad marketing from certain manufacturers to sell more, is just hilarious ... as what they said against the Technics direct drive ... come on.

Funny all this given I recommend a Technics 1210 with it's non-rigid arm as a good match for a Denon DL-103 cartridge.

And somehow everyone jumps on what I write to make an argument out of it that states in different ways what I wrote.

Thor

 

[anmpr1]

That's just a common audiophile myth.

I think @Frank Dernie was doing this sort of measurement at Garrard, back in the day. From his posts, that's where I first encountered the idea of resonances from a removable shell--resonances that you didn't get with a fixed arm.

From practical, day to day, use, I always prefer a removable headshell. If you never change cartridges, it's probably not much of an ergonomic issue.

 

[anmpr1]

SME uses removable headshells ... i doubt SME do crappy stuff

SME has at times offered removable headshells, fixed connections, and even removable wands. The latter you could get with an integrated Ortofon Concorde cartridge.

 

[mike70]

Alas, it is not. We are dealing with resonant mechanical systems here.

Thor

I did not suggest rigid arms were better. I suggested that for the DL-103 a rigid arm is a poor match.



I wrote nothing about removable headshell's being bad.



Funny all this given I recommend a Technics 1210 with it's non-rigid arm as a good match for a Denon DL-103 cartridge.

And somehow everyone jumps on what I write to make an argument out of it that states in different ways what I wrote.

Thor

That's ok then. Normally we are bored to death with all that bad manufacturer marketing ... my apologies.

 

[mike70]

I think @Frank Dernie was doing this sort of measurement at Garrard, back in the day. From his posts, that's where I first encountered the idea of resonances from a removable shell--resonances that you didn't get with a fixed arm.

From practical, day to day, use, I always prefer a removable headshell. If you never change cartridges, it's probably not much of an ergonomic issue.

check the Korf Blog.

 

[Frank Dernie]

That's just a common audiophile myth.

No it isn’t.
I measured resonances due to the detachable fixing on a SME 3009 strong enough to show up on the cartridge output, this would be in 1976 I suppose. Funnily enough the clip in plastic cartridge slide in the then current Garrard arms behaved better than the much vaunted (and expensive) SME.

I actually put my SME 3009 Improved in a skip with plinth and Technics SP10, nowadays it would have been worth a fair bit. If only I’d known!

It is convenient to be able to change cartridges and it is a big deal for some enthusiasts (who perhaps enjoy changing cartridges more than listening to music )

FWIW I was only concerned by anything which showed up on the cartridge output, not any random vibration anywhere else.

 

[thyristor]

To: Bernard23

If you can get or make yourself a USB to a suitable DC-jack cable you could power Ifi Zen Phono from a power bank. That would rule out the possible hum issues from mains.

I have no issues with hum or noise with my Zen Phono but I'm thinking about trying to run it from a power bank.

But as Amir's measurements show the power filtering in Zen Phono is very effective so there isn't a need for "cleaner" power supply.

 

[mike70]

FWIW I was only concerned by anything which showed up on the cartridge output, not any random vibration anywhere else.

but the cartridge is in touch with the headshell, not with the tonearm itself ... the headshell is the platform for the cartridge and where you have the "vibration anywhere" results.
The measurement is about the "anywhere".

you can have a bad compliance cartridge / tonearm - headshell system and the cartridge output can be worst with a better tonearm - headshell.

 

[Thorsten Loesch]

I think @Frank Dernie was doing this sort of measurement at Garrard, back in the day. From his posts, that's where I first encountered the idea of resonances from a removable shell--resonances that you didn't get with a fixed arm.

That is more or less the opposite of what happens. A removable headshell creates a mechanical break where resonances are damped.

Mind you, the proliferation of rigid arms means many modern cartridges are designed to work with that sort of arm. Many are super expensive as well. It's all about resonant mechanical systems with frequencies in the kHz range.

As I see cartridges as consumables (both in guns and turntables) I prefer affordable quality. So a DL-103 on a non rigid arm with raised arm mass to get the VLF arm resonance right works for me.

Thor

 

[Thorsten Loesch]

To: Bernard23

If you can get or make yourself a USB to a suitable DC-jack cable you could power Ifi Zen Phono from a power bank. That would rule out the possible hum issues from mains.

This works, but you need to recharge. If you permanently attach a charger to the battery bank all problems are back.

I recommend the cheap (30 USD) linear power supplies from China (AliExpress). They have no earth and by using 2-Chamber safety transformers they have the lowest coupling capacitance from mains to output (much lower than the fat toroidal Transformers in many expensive linear PSU's.

I have no issues with hum or noise with my Zen Phono but I'm thinking about trying to run it from a power bank.

If no noise, no need.

Only the control logic circuits run directly from the 5V.

For the audio circuits there is a 1.2MHz step-up switcher that produces appx. +/-12V followed by LC filtering and discrete low noise regulators for the main phono stage. The MC stage has another round of regulation.

Thor

 

[Frank Dernie]

but the cartridge is in touch with the headshell, not with the tonearm itself ... the headshell is the platform for the cartridge and where you have the "vibration anywhere" results.
The measurement is about the "anywhere".

you can have a bad compliance cartridge / tonearm - headshell system and the cartridge output can be worst with a better tonearm - headshell.

That is more or less the opposite of what happens. A removable headshell creates a mechanical break where resonances are damped.

This simply shows a lack of understanding of dynamic systems and how pickup cartridges work, I'm afraid.

 

[Thorsten Loesch]

This simply shows a lack of understanding of dynamic systems and how pickup cartridges work, I'm afraid.

We can debate that. But having had a Turntable quite Armed (and dangerous - pun intended) for quite a while it is easy to be empirical.

A Rega arm has significantly more felt armtube movement playing pink noise than a SME 3009 or a 9" Ortofon.

Conclusion, the coupling of energy from the stylus between cartridge/headshell and actual arm is less for a non-rigid arm. It also makes sense from a simple mechanical engineering view.

What does that do to the cartridge output? Resonances (not fundamental LF resonance) are more damped, which is generally a good thing.

Thor

 

[Frank Dernie]

It also makes sense from a simple mechanical engineering view.

This is, and has been, the problem with discussions I have seen on the interent and magazines about record players for decades. It isn't that simple.

People, even some engineers, apply static thinking to dynamic systems because they are hard to "visualise". Even one of my old engineering bosses 50 years ago told me he saw what the maths said but couldn't get his head round it. As a young engineer I was used to installations where, say, a motor, speed reducer and pump were all chosen by an application engineer based on power and flow requirements, assembled together and had a vibration problem because the assembly had a resonance in the running range which none of the individual components had.

Dynamic systems are complex and thinking of them the way many people do just leads to wrong conclusions IME, I'm afraid, but they are ubiquitous.

Record players have always been complex assemblies and, it seems to me, are less well generally understood than they were 50 years ago, probably due to the amount of misinformation in the internet nowadays.

 

[Thorsten Loesch]

This is, and has been, the problem with discussions I have seen on the interent and magazines about record players for decades. It isn't that simple.

People, even some engineers, apply static thinking to dynamic systems because they are hard to "visualise". Even one of my old engineering bosses 50 years ago told me he saw what the maths said but couldn't get his head round it. As a young engineer I was used to installations where, say, a motor, speed reducer and pump were all chosen by an application engineer based on power and flow requirements, assembled together and had a vibration problem because the assembly had a resonance in the running range which none of the individual components had.

Dynamic systems are complex and thinking of them the way many people do just leads to wrong conclusions IME, I'm afraid, but they are ubiquitous.

Record players have always been complex assemblies and, it seems to me, are less well generally understood than they were 50 years ago, probably due to the amount of misinformation in the internet nowadays.

Let's keep it simple.

We have a mostly fixed point (bearings, yes, they have tolerance and losses) linked to a relatively high mass.

We have a second point that is elastically suspended and is vibrated mechanically (stylus and cantilever) linked to a second relatively moderate mass. Multiple resonances happen on the small stylus/cantilever and moderate mass system, including stylus/vinyl resonance and any structural resonances of members of this system.

For the best accuracy in the stylus tracing the information cut into the groove the second point is absolutely unmovable, but other requirements of the LP system require relatively free movement of second point in the lateral and vertical planes at very low frequencies (<<20Hz),

We have a structural member linking these two points, which can either be made in a single piece (with a variety of geometries) or in more than one piece.

If more than one piece is used commonly the structural break(s) occur near the two ends of the structural member. They commonly use some form dissimilar materials and press fit. At the energy input end the press-fit is often combined with a compliant elements that creates tension in the press-fit.

Which system is better able to damp unwanted resonances in the input system? Rigid/same material, or non-rigid with multiple materials?

My Ortofon Arm has the counterweight suspended by rubber, creating a lossy, damped coupling resisting movement at higher frequencies in the whole system.

Do you maintain my understanding of the systemic issues if wrong?

If so please correct me.

Thor

 

[Frank Dernie]

Let's keep it simple.

We have a mostly fixed point (bearings, yes, they have tolerance and losses) linked to a relatively high mass.

We have a second point that is elastically suspended and is vibrated mechanically (stylus and cantilever) linked to a second relatively moderate mass. Multiple resonances happen on the small stylus/cantilever and moderate mass system, including stylus/vinyl resonance and any structural resonances of members of this system.

For the best accuracy in the stylus tracing the information cut into the groove the second point is absolutely unmovable, but other requirements of the LP system require relatively free movement of second point in the lateral and vertical planes at very low frequencies (<<20Hz),

We have a structural member linking these two points, which can either be made in a single piece (with a variety of geometries) or in more than one piece.

If more than one piece is used commonly the structural break(s) occur near the two ends of the structural member. They commonly use some form dissimilar materials and press fit. At the energy input end the press-fit is often combined with a compliant elements that creates tension in the press-fit.

Which system is better able to damp unwanted resonances in the input system? Rigid/same material, or non-rigid with multiple materials?

My Ortofon Arm has the counterweight suspended by rubber, creating a lossy, damped coupling resisting movement at higher frequencies in the whole system.

Do you maintain my understanding of the systemic issues if wrong?

If so please correct me.

Thor

This is a common set of non sequiturs, based on an absence of education in the basic physics, I suspect.

You need to go back to study the maths and look at what happens when you have distributed mass, lumped mass, elasticity and damping and what happens when you make a new dynamic system by joining 2 separate systems together. It is complex.

They can not be considered separately in a dynamic situation and since a record player is a vibration (groove modulation) measuring device the whole system needs analysing as an assembly.

Pickup arms and cartridges being sold separately is a historical artefact of the business, not a sound engineering based reason.

Anyway years of study are needed to understand the maths (it was for me) and get the analysis right and I am not a teacher, just an engineer with 50 years exasperating experience of resolving dynamic system unexpected responses when they were assembled by people using quasi-static thinking.

 

[Thorsten Loesch]

This is a common set of non sequiturs, based on an absence of education in the basic physics, I suspect.

I am trying to keep it simple.

Npote, I treat the whole system.

You need to go back to study the maths and look at what happens when you have distributed mass, lumped mass, elasticity and damping and what happens when you make a new dynamic system by joining 2 separate systems together. It is complex.

It is indeed complex. But I am interested in answers to first order effects first.

They can not be considered separately in a dynamic situation and since a record player is a vibration (groove modulation) measuring device the whole system needs analysing as an assembly.

We are in complete agreement.

Pickup arms and cartridges being sold separately is a historical artefact of the business, not a sound engineering based reason.

Well, there is that. Some manufacturers deliberately engineered their Pickup's with specific assumptions about the Arm to be used.

Anyway years of study are needed to understand the maths (it was for me) and get the analysis right and I am not a teacher, just an engineer with 50 years exasperating experience of resolving dynamic system unexpected responses when they were assembled by people using quasi-static thinking.

Hmm, why not show a model of this then?

Thor