RF free Prefix
Posted by: Chris Bell on 13 March 2003
I just had a new prefix installed in my LP-12 which is RF free! Yes, RF free! Before, both the old Prefix (K) and Stageline (K) had terrible RF (Seattle radio stations). Now nothing but fantastic sound. Anyone who yerns for a Prefix but had terrible RF should run to their dealer. I am already contemplating a Supercap for mine.
Chris Bell
PS: Many thanks to Chris Koster for sending me the new improved Prefix...I was ready to buy a Groove or maybe that Boulder phono pre-amp (not).
Chris Bell
PS: Many thanks to Chris Koster for sending me the new improved Prefix...I was ready to buy a Groove or maybe that Boulder phono pre-amp (not).
Posted on: 27 December 2003 by sean
Someone stated earlier that the 'K' prefix sounds better than the 'S' version. Anyone had a similar experience? I just found out I have an 'S' model and have been using a Troika and other Linn carts for about 10 years. Changed to a Helicon and instantly far more gain. Turns out I had the wrong fitted, as supplied by my dealer!
I was speaking to Richard Dane recently about updating my prefix to the RF free version and changing to the 'S' version (I thought I had a 'K') to match the Helicon and he advised against it. Some feedback would be nice as it is possible to get the prefix changed and anything to get a little improvement in sound is always appreciated.
Sean.
I was speaking to Richard Dane recently about updating my prefix to the RF free version and changing to the 'S' version (I thought I had a 'K') to match the Helicon and he advised against it. Some feedback would be nice as it is possible to get the prefix changed and anything to get a little improvement in sound is always appreciated.
Sean.
Posted on: 27 December 2003 by John
Sean:
I have both the S and K versions (new spec). Follow Naims advise on matching because the S is not just a filtered K. I have an XX2 and the S seems to be a perfect match. The K initially seemed to have more definition in the high end but over time I realized the mid-bass was sucked out of the presentation only emphasizing the highs. The strings on guitars were highly detailed but lacked the wood/weight of the guitar. I only ran the K for 4 days before I pulled it. It just didn't sound right. There was no sibilence and nothing negative but the presentation was thrown off balance. I plan to try it again soon to see if my initial impression was correct.
John
I have both the S and K versions (new spec). Follow Naims advise on matching because the S is not just a filtered K. I have an XX2 and the S seems to be a perfect match. The K initially seemed to have more definition in the high end but over time I realized the mid-bass was sucked out of the presentation only emphasizing the highs. The strings on guitars were highly detailed but lacked the wood/weight of the guitar. I only ran the K for 4 days before I pulled it. It just didn't sound right. There was no sibilence and nothing negative but the presentation was thrown off balance. I plan to try it again soon to see if my initial impression was correct.
John
Posted on: 27 December 2003 by bdnyc
Sean-
The other issue you should bring up with your dealer is whether you use the "SL" version of the Lyra Helikon or the normal one. The "SL" output levels are very close to the fairly low output of the Linn cartridges that the "K" boards were made for, where the "regular Helikon" is a higher output MC (medium output really), more in line with contemporary users, especially folks who runs tubes in either their phono stage or pre-amp, and may not have sufficient gain, or a low enough noise floor to really benifit from the SL.
As far as which Naim phono stage is a better fit for a Lyra cartridge, I have only heard the K version with a Helikon SL, and that is spectacular.
Good luck.
The other issue you should bring up with your dealer is whether you use the "SL" version of the Lyra Helikon or the normal one. The "SL" output levels are very close to the fairly low output of the Linn cartridges that the "K" boards were made for, where the "regular Helikon" is a higher output MC (medium output really), more in line with contemporary users, especially folks who runs tubes in either their phono stage or pre-amp, and may not have sufficient gain, or a low enough noise floor to really benifit from the SL.
As far as which Naim phono stage is a better fit for a Lyra cartridge, I have only heard the K version with a Helikon SL, and that is spectacular.
Good luck.
Posted on: 28 December 2003 by silklee
So specs wise, should a helikon (non SL version) go with the K or S prefix?
Posted on: 28 December 2003 by Chris Koster
Nana is doing updates to take non-RF resistant Prefixes to the current RF resistant spec. This mod costs $100.00 and takes a week or less.
It also is available for the Stageline.
It also is available for the Stageline.
Posted on: 28 December 2003 by sean
Everyone,
Thanks for the replys. First off I bought my Helicon ex dem from a dealer in England (blind and for a reasonable sum, I really wanted an Akiva, but funds and the like) not my local dealer so trying an SL version from him will be a no no.
Chris, I believe you were instrumental in getting a low output version of the Helicon to see the light of day. What did you find did'ent quite match with the prefix in the standard version? and did you use an S or K prefix with it?
John, I will look forward to hearing how you get on trying the K prefix again.
Sean.
Thanks for the replys. First off I bought my Helicon ex dem from a dealer in England (blind and for a reasonable sum, I really wanted an Akiva, but funds and the like) not my local dealer so trying an SL version from him will be a no no.
Chris, I believe you were instrumental in getting a low output version of the Helicon to see the light of day. What did you find did'ent quite match with the prefix in the standard version? and did you use an S or K prefix with it?
John, I will look forward to hearing how you get on trying the K prefix again.
Sean.
Posted on: 28 December 2003 by aht
Chris--
If the RF upgrade is now available for the Stageline, what about current production? If I buy a new Stageline, will it be the RF-resistant version?
Arthur
If the RF upgrade is now available for the Stageline, what about current production? If I buy a new Stageline, will it be the RF-resistant version?
Arthur
Posted on: 29 December 2003 by silklee
Hi Chris Koster,
You got a pte topic.
Rgds.
You got a pte topic.
Rgds.
Posted on: 29 December 2003 by NaimDropper
My understanding of the difference between the S and K boards is the cartridge loading.
There is tons (tonnes) of information on that topic out there but it boils down to the electrical loading of the "generator" that is the cartridge. (Some call it a "motor" and I won't argue the point.) If the cart is not properly loaded you will have a resulting frequency and phase response that is FAR from flat, especially in the mid-range if my memory serves.
This effect is not subtle.
Most all of the Linn MC carts require the K boards and most all other types require the S, but "most" is the operative word here. And there may be still others that require other compensation not included by the S or K input impedances. (I have no experience with the Helicon.) Thankfully it's only a matter of a resistor and capacitor across the input...
Further (again if my understanding is correct), the Prefix, since it significantly shortens the phono cable, has slightly different values for the compensation vs. the 323 or 523 series boards.
Dealers and installers should be completely familiar with this and shame on them if they're not!
David
(edited for grammar and clarity)
[This message was edited by NaimDropper on TUESDAY 30 December 2003 at 03:13.]
There is tons (tonnes) of information on that topic out there but it boils down to the electrical loading of the "generator" that is the cartridge. (Some call it a "motor" and I won't argue the point.) If the cart is not properly loaded you will have a resulting frequency and phase response that is FAR from flat, especially in the mid-range if my memory serves.
This effect is not subtle.
Most all of the Linn MC carts require the K boards and most all other types require the S, but "most" is the operative word here. And there may be still others that require other compensation not included by the S or K input impedances. (I have no experience with the Helicon.) Thankfully it's only a matter of a resistor and capacitor across the input...
Further (again if my understanding is correct), the Prefix, since it significantly shortens the phono cable, has slightly different values for the compensation vs. the 323 or 523 series boards.
Dealers and installers should be completely familiar with this and shame on them if they're not!
David
(edited for grammar and clarity)
[This message was edited by NaimDropper on TUESDAY 30 December 2003 at 03:13.]
Posted on: 30 December 2003 by John
Well I had a chance to reinstall the K prefix again and let it settle in for 2 days. This time I used my CD recorder and recorded music so I could easily compare the S and Ks diffenence.
In context of the XX2, the K is not a better prefix than the S. The only difference between them is the articulation of the bass. The bass is thinner on the K (almost dissapearing in some recordings) giving emphasis to the mids and highs. I initially had the impression again that vocals/mids were clearer with the K but switching to the recorded CD it was obvious it was the bass being thinner. There was actually no difference between the S and K in the mids and highs. Keep in mind this is with the new spec prefixes and I did notice a significant improvement from the old S to the new. So there might be a difference between the older S and K. My system is 52/Super/135/NBLs. The results also might change when the prefix is hicapped or supercapped.
I hope this helps someone. I needed to understand if the S is just a filtered K and if the K is better. BTW, the differences were 100% as Steve K. at NANA described. Thanks Steve! I didn't doubt you I was just seduced into the possibility of better music.
Now that I have a K and S prefix. Should I keep the K for future cartridge changes? Besided the Helikon SL and Linn cartridges what else is a prefect match with the K?
John
In context of the XX2, the K is not a better prefix than the S. The only difference between them is the articulation of the bass. The bass is thinner on the K (almost dissapearing in some recordings) giving emphasis to the mids and highs. I initially had the impression again that vocals/mids were clearer with the K but switching to the recorded CD it was obvious it was the bass being thinner. There was actually no difference between the S and K in the mids and highs. Keep in mind this is with the new spec prefixes and I did notice a significant improvement from the old S to the new. So there might be a difference between the older S and K. My system is 52/Super/135/NBLs. The results also might change when the prefix is hicapped or supercapped.
I hope this helps someone. I needed to understand if the S is just a filtered K and if the K is better. BTW, the differences were 100% as Steve K. at NANA described. Thanks Steve! I didn't doubt you I was just seduced into the possibility of better music.
Now that I have a K and S prefix. Should I keep the K for future cartridge changes? Besided the Helikon SL and Linn cartridges what else is a prefect match with the K?
John
Posted on: 30 December 2003 by sean
John,
Thanks for the reply. It looks like the S fits the bill better for medium output carts. My Helicon sounds extremely detailed and lacking in a little flow at the moment. As I bought it ex dem I've no idea how many hours it has on it so I'll keep my fingers crossed that it smoothes out. It is so long since I ran in a new cartridge the I can't remember how a brand new one sounds. Bright and lacking in any musical pleasure seems to ring a bell, but there is some pleasure with the Helicon. Also with the Helicon it is impossible to get it far enough back in the headshell (I have an Ekos) to get the right 'arm pivot point to stylus tip' dimension. It looks around 5mm longer than the Troika. How critical is this measurement to get the correct sound from the cartridge? I'd imagine that Aro users have the same problems because of the pre drilled holes but I know that the Helicon is a popular choice with it.
If there are any TT set up experts out there with any ingenious solutions then answers on a postcard please.
Sean.
Thanks for the reply. It looks like the S fits the bill better for medium output carts. My Helicon sounds extremely detailed and lacking in a little flow at the moment. As I bought it ex dem I've no idea how many hours it has on it so I'll keep my fingers crossed that it smoothes out. It is so long since I ran in a new cartridge the I can't remember how a brand new one sounds. Bright and lacking in any musical pleasure seems to ring a bell, but there is some pleasure with the Helicon. Also with the Helicon it is impossible to get it far enough back in the headshell (I have an Ekos) to get the right 'arm pivot point to stylus tip' dimension. It looks around 5mm longer than the Troika. How critical is this measurement to get the correct sound from the cartridge? I'd imagine that Aro users have the same problems because of the pre drilled holes but I know that the Helicon is a popular choice with it.
If there are any TT set up experts out there with any ingenious solutions then answers on a postcard please.
Sean.