Hi Jacco,
Unfortunately, I do not have the schematic for this 15-year old Phonon which is usual of Japanese gears.
This was one-off product from a group of pro-carsound enthusiast engineers and was designed by the same group who is responsible for current BEWITH products (new fundings) today which also does not release their schematics. They had then contracted manufacturing to a Japanese OEM mfr who now manufactures RF and other high-bandwith scientific and industrial products.
BEWITH
Phonons car amps were only released under the guise of the 4-channel 340C and the 2-channel 320C and yes, some still swear by it for the vocal and power from this 4X60 and 2X60 watts amps. I had spent some time with both Bewith and Phonon amps + Audisons VRX, Zapco Competition Series, Genesis Dual mono etc. and still went back to Phonon amps which I collected 7 units in the last 5 years.
Somehow, these 2 products were the first and last that was released before the group dissolved but not before being recognised as one of the top if not the top Japanese car amp as recent as until today. Guess that key reason was that this rare amp outside Asia of zero feedback topology and Class A design which was sold at about 300k Yen or USD3k each back in mid 90s!
Most importantly, my subjective assessment of the Phonon 340C with obvious preference for audiophile and casual music of Jazz, Vocal, etc. (certainly not bass head) is as follows:
- Analog or warm sounding but yet clear and powerful (certainly not clinical)
- Nice depth and "being there" .... airy and never right-in-your face
- Great extension ... the jingles and cymbals stays till the end (can't say about the low extension as I only have an 8" sub and suspect not its strength due to Class A topology and low output for typical subs but the mid bass is fine while being rounded and not hard-hitting
- Full bodied
My apology for being far off-topic but believe my passion for this Phonon 340C explain my venture into Op Amp replacement (also the subjective 'BG N' caps swap).
I will take photos of my set-up with 3X phonon 340C in customised enclosure that had been fully refurnished with 2k paint in original orange and original NOS Nichicon FA, Nichicon NP ES, Nichicon FME etc. capacitors if anyone is interested.
Regards,
Richard
Car-Audio setup: Alpine CDA-7998R, PXA-H900, DVA-S680E, CHA-S609, TUA-T100DAB, Phonon 340C (3X), Micro Precision z-series Tweeters, Z-series Mid and SEAS reference midbass, Rainbow Vanadium 8" Sub, Belden speaker cable, Mogami IC (soon-to-be Bewith LC RCA)
Unfortunately, I do not have the schematic for this 15-year old Phonon which is usual of Japanese gears.
This was one-off product from a group of pro-carsound enthusiast engineers and was designed by the same group who is responsible for current BEWITH products (new fundings) today which also does not release their schematics. They had then contracted manufacturing to a Japanese OEM mfr who now manufactures RF and other high-bandwith scientific and industrial products.
BEWITH
Phonons car amps were only released under the guise of the 4-channel 340C and the 2-channel 320C and yes, some still swear by it for the vocal and power from this 4X60 and 2X60 watts amps. I had spent some time with both Bewith and Phonon amps + Audisons VRX, Zapco Competition Series, Genesis Dual mono etc. and still went back to Phonon amps which I collected 7 units in the last 5 years.
Somehow, these 2 products were the first and last that was released before the group dissolved but not before being recognised as one of the top if not the top Japanese car amp as recent as until today. Guess that key reason was that this rare amp outside Asia of zero feedback topology and Class A design which was sold at about 300k Yen or USD3k each back in mid 90s!
Most importantly, my subjective assessment of the Phonon 340C with obvious preference for audiophile and casual music of Jazz, Vocal, etc. (certainly not bass head) is as follows:
- Analog or warm sounding but yet clear and powerful (certainly not clinical)
- Nice depth and "being there" .... airy and never right-in-your face
- Great extension ... the jingles and cymbals stays till the end (can't say about the low extension as I only have an 8" sub and suspect not its strength due to Class A topology and low output for typical subs but the mid bass is fine while being rounded and not hard-hitting
- Full bodied
My apology for being far off-topic but believe my passion for this Phonon 340C explain my venture into Op Amp replacement (also the subjective 'BG N' caps swap).
I will take photos of my set-up with 3X phonon 340C in customised enclosure that had been fully refurnished with 2k paint in original orange and original NOS Nichicon FA, Nichicon NP ES, Nichicon FME etc. capacitors if anyone is interested.
Regards,
Richard
Car-Audio setup: Alpine CDA-7998R, PXA-H900, DVA-S680E, CHA-S609, TUA-T100DAB, Phonon 340C (3X), Micro Precision z-series Tweeters, Z-series Mid and SEAS reference midbass, Rainbow Vanadium 8" Sub, Belden speaker cable, Mogami IC (soon-to-be Bewith LC RCA)
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Hi richard,
I think that the double test you're going to do is a wise decision, at leat you could find if only one or both your mods are the culprit.
Regarding your past experience with Silmics it's not surprising if the design provides bypass caps for elcos; also, somethimes, too much Silmics in a design is no good if other caps are not perfectly transparent (like ceramics as filter caps).
Regarding the opamp probably an OPA132/OPA2132 woud have been a no brainer swap, the OPA627 requires some care to sound at its best and has higher power requirements.
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Hi ClaveFremen,
Should have indeed known better than to think that dual OPA627 can be a direct drop-in replacement for the NJM353 without any further work ... it was a case of lack of knowledge to read the datasheets and the "greed" to use the commonly referred "best op amp" of OPA627.
I may also try the OPA2107 that I already have on hand since the specification looks awefully close to NJM353 and believe it is also considered "higher/better" than OP2132 which I do not have ... please let me know if otherwise.
If both original NJM353 and OPA2107 replacing the the dual OPA627 do not yielded at least the SQ the original amp, i will get rid of the BG N input coupling/analog bypass caps and put back the Nichicon ES also.
Regards,
Richard
Should have indeed known better than to think that dual OPA627 can be a direct drop-in replacement for the NJM353 without any further work ... it was a case of lack of knowledge to read the datasheets and the "greed" to use the commonly referred "best op amp" of OPA627.
I may also try the OPA2107 that I already have on hand since the specification looks awefully close to NJM353 and believe it is also considered "higher/better" than OP2132 which I do not have ... please let me know if otherwise.
If both original NJM353 and OPA2107 replacing the the dual OPA627 do not yielded at least the SQ the original amp, i will get rid of the BG N input coupling/analog bypass caps and put back the Nichicon ES also.
Regards,
Richard
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According to datasheets, If I'm interpreting them correctly, NJM353 draws 3.6 mA (it's not clear if both amplifers or only one), OPA2132 4mA per amplifier (so 8mA total), OPA2107 4.5 mA per amplifier (so 9 mA total) and OPA627 7 mA (so in a dual config on Browndogs 14 mA total).
An interesting but untested alternative could be OPA1642 that draws only 1.8 ma (3.6 mA total).
Since NJM353 is a FET opamp it should be easier to find a better and compatible one between FET opamps (so no OPA1612).
In my experience OPA2132 is far better than any NJM opamp and better than NE5532.
But pay attention that differences are bigger with film/C0G filter (in the signal path) caps so if your circuit uses cheap ceramics as filter caps differences could be not so big.
I've OPA2107s but I didn't compared them with OPA2132 since in this moment I don't have any OPA2132 to swap.
I suggest you, if you didn't already, to mount sockets for an easy and safe opamp rolling.
Then try OPA2107 that you already have and eventually other opamps
Once you settle on your preferred opamp you can solder it (safer in a car environment).
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Apart OPA2107 your numbers are identical to mines...
Since tables in BB datasheet usually give data of a single amplifier I've interpreted it in this way but probably you're right.
I've used ZLs/ZLHs for years but in both my SACD player and receiver Panny FC and Silmics sounded much more balanced...
When I've done component selection for my MyRef I've also tried again ZLs (compared to FMs, Silmics, Fine Gold, KW) and I've found them again weird sounding with a grey midrange.
Different taste?
Woww... Richard ...... You really do have some holy grains there
.. I guess you are the only one in Singapore with the most number of phonon amps in your boot. I suggest not to carry on op-amp rolling till you change all cables you wishes to upgrade then you change the op-amp to the one that suit your taste.
I suspect its the Mogami IC causing the bit of fuzziness in the sound that you are hearing. Bewith RCA will sound to your liking, I guess. (I believe in system matching therefore the above comments).
I found a reference whereby the authentic Soundblaster X-Fi cards had their output op-amp replaced with LME49860.
These models included X-Fi X-Treme Music and X-Fi Gamer that are equipped by Creative Labs with the original X-Fi 51 million transistor sound processor chip. The documentation of the op-amp upgrade and its merits, was on-line in the year 2007 and has since gone missing.
As I remember, this upgrade was popular in its day. This was probably prior to the availability of inexpensive Via Tremor cards for $14 on e-bay.
I do remember my X-Fi, which was inappropriately over-sensitive to the quality of the power within the computer, especially the power circuits of the motherboard and the power supply as well. I have one old computer that I have preserved as far as possible. Its an Athlon Barton with a Via board and an old model Fortron Source power supply. The X-Fi Xtreme Music works satisfactorily in that computer, but it doesn't produce significant quality in my other, newer computers.
Any ideas?
Have you, or do you know someone who has, upgraded their X-Fi with LME49860?
These models included X-Fi X-Treme Music and X-Fi Gamer that are equipped by Creative Labs with the original X-Fi 51 million transistor sound processor chip. The documentation of the op-amp upgrade and its merits, was on-line in the year 2007 and has since gone missing.
As I remember, this upgrade was popular in its day. This was probably prior to the availability of inexpensive Via Tremor cards for $14 on e-bay.
I do remember my X-Fi, which was inappropriately over-sensitive to the quality of the power within the computer, especially the power circuits of the motherboard and the power supply as well. I have one old computer that I have preserved as far as possible. Its an Athlon Barton with a Via board and an old model Fortron Source power supply. The X-Fi Xtreme Music works satisfactorily in that computer, but it doesn't produce significant quality in my other, newer computers.
Any ideas?
Have you, or do you know someone who has, upgraded their X-Fi with LME49860?
Just a quick update.
Had to remove the OPA627AU on brown dog adaptor due to DC leakage in 2 out of the 3 modded Phonon amps and replaced with OPA2107AP without any problem. Tried the LME49860NA and similarly spec'ed LME49720HA and not able to bias the voltage to stabilise the amp, eliminate DC leakage and high heat just like OPA627AU. Not sure if this DC leakage and high heat is due to oscillation or other reasons since I am an electronic noob but will assume to be the case and move on.
Did not try the OPA1642 since I got a bit jaded after all the effort and just too little positive review available on its sound quality to motivate me on the extra effort.
Aside to FFFO,
--------------
Not sure about in Singapore with 7 Phonon amps but certainly not more than the 12 NOS Phonon 340C that the Phonon designer in Japan still keep in his private collection but available for 400kYen each:
?????? ???????????????????????????????? - ?????SNS???????????????
View topic - Anyone know about Phonon amps? 340C / 320C
Cheers,
Richard
Had to remove the OPA627AU on brown dog adaptor due to DC leakage in 2 out of the 3 modded Phonon amps and replaced with OPA2107AP without any problem. Tried the LME49860NA and similarly spec'ed LME49720HA and not able to bias the voltage to stabilise the amp, eliminate DC leakage and high heat just like OPA627AU. Not sure if this DC leakage and high heat is due to oscillation or other reasons since I am an electronic noob but will assume to be the case and move on.
Did not try the OPA1642 since I got a bit jaded after all the effort and just too little positive review available on its sound quality to motivate me on the extra effort.
Aside to FFFO,
--------------
Not sure about in Singapore with 7 Phonon amps but certainly not more than the 12 NOS Phonon 340C that the Phonon designer in Japan still keep in his private collection but available for 400kYen each:
?????? ???????????????????????????????? - ?????SNS???????????????
View topic - Anyone know about Phonon amps? 340C / 320C
Cheers,
Richard
The LME49720HA in my DAC run hots and cannot go without some sort of heatsink without overheating (creates serious distortion).
I considered Phonon before but in end went with Bewith for convenience.
Oh yes, I saw you are using PC PSU (switching mode PS), from what I understand those PS will introduce some noise into the amps thus when you shift your amps (after tuning) into the car, the sound will be different again. Why will you choose NOS electrolytic caps? As far as I know, electrolytic capacitors have a life span of 15yrs max before problem arise whether used or not.
I considered Phonon before but in end went with Bewith for convenience.
Oh yes, I saw you are using PC PSU (switching mode PS), from what I understand those PS will introduce some noise into the amps thus when you shift your amps (after tuning) into the car, the sound will be different again. Why will you choose NOS electrolytic caps? As far as I know, electrolytic capacitors have a life span of 15yrs max before problem arise whether used or not.
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Hmm... I am not sure about it. I just replace a NE5532 with this, I have no scope to check this though. I have another friend whom too mentioned that its hot in another application.
The LME49720 has a quiescent current of approx 10 to 12 ma so should be slightly warm to touch on -/+ 15v supplies.
If it's "hot" it's either unstable in that application, or there is a DC offset causing it to force current into a low impedance.It shouldn't be any different temperature wise to a 5532.
If it's "hot" it's either unstable in that application, or there is a DC offset causing it to force current into a low impedance.It shouldn't be any different temperature wise to a 5532.
Hi FFFO,
The PC PSU is just to run in the 3 units "experimental" Phonon 340c for the last >1 month 24/7 or >>500 hours to leave no doubt on the concern of the Blackgate NX 10uF 50V input capacitors that I swapped with the original Nichicon ES 10uF 16V.
These 3 amps will be installed to replace the 3 units of original Phonon 340c with NOS caps in my current setup to hope to see improvement with these famed Blackgates but use of NOS caps others is to preserves the original sounds as the reference when replacing the presumable worn out capacitors.
Most of these NOS caps are datecodes around 2000 with Nichicon ES being available in 2009 datecode and I had them reformed ... so far so good.
Yes, going with Bewith amps would have been less complicated (and cheaper even) but less satisfactory than getting these rare Phonon 340c to be refurbished with new coat of paint and recapped with these hard-to-get Nichicon FA capacitors. It had also been a good learning experience for me on understanding how car amp works, about ops amp, capacitors etc. The Class A and ZeroFeedback topologies is also no longer implemented in Bewith amps and I do think it makes a significant differences in the sound quality.
Regards,
Richard
The PC PSU is just to run in the 3 units "experimental" Phonon 340c for the last >1 month 24/7 or >>500 hours to leave no doubt on the concern of the Blackgate NX 10uF 50V input capacitors that I swapped with the original Nichicon ES 10uF 16V.
These 3 amps will be installed to replace the 3 units of original Phonon 340c with NOS caps in my current setup to hope to see improvement with these famed Blackgates but use of NOS caps others is to preserves the original sounds as the reference when replacing the presumable worn out capacitors.
Most of these NOS caps are datecodes around 2000 with Nichicon ES being available in 2009 datecode and I had them reformed ... so far so good.
Yes, going with Bewith amps would have been less complicated (and cheaper even) but less satisfactory than getting these rare Phonon 340c to be refurbished with new coat of paint and recapped with these hard-to-get Nichicon FA capacitors. It had also been a good learning experience for me on understanding how car amp works, about ops amp, capacitors etc. The Class A and ZeroFeedback topologies is also no longer implemented in Bewith amps and I do think it makes a significant differences in the sound quality.
Regards,
Richard
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Hi Mooly,
Now it sounds worrying. From the sounding, I dont think I can hear any problems. The application is buffers used in Lite Audio DAC-AM.
Do you suspect any problem or how can I check without a scope? I only have a DMM.
Even though I have not heard it myself but acoording to my Sifu, I will agree.... I think Bewith 'reference' amps are just too clean/ too lean for some. System Matching is critical if not, it will sound lifeless/ boring but excellent Hi-fi attributes. However, the 'confidence' series monoblocks might be different though.
These amps including Phono need warm up time, 15~30mins will be good
but on this sunny island.... hahaha... 45~1hr from east to west. I think you should start sourcing for different semiconductors as I have had people failed to repair them due to lack of compatible parts even if it was sent back to Japan. Heat will be a major issue for this amp and that will cause alot of componets to fail so just take care of this point.
Hi guys! I've just tweaked three cdplayers. I've changed the opamps in the analog stage of a Sony CDP950, A philips CD930 and a Marantz CD48.
Marantz cd48 have just one opamp but a dual one. The Sony and the philips have two dual opamps. After I've replaced the original opamps with opamp sockets I have tried: 2X LM 4562 in Sony and in Philips and one in Marantz, and the same I've put OPA 2134 and OPA 2604.
Sony sounded very cool with each. My favourite is Philips with OPA 2604 wich sounds very rich , very warm and very relaxed and natural. The worse is Marantz wich sound very poor, non-dynamic but relaxed. In Marantz the best was OPA 2134.
Every opamp have his own sound. It depends of what you prefer. Here is not good or bad, just what you like or don't.
Marantz cd48 have just one opamp but a dual one. The Sony and the philips have two dual opamps. After I've replaced the original opamps with opamp sockets I have tried: 2X LM 4562 in Sony and in Philips and one in Marantz, and the same I've put OPA 2134 and OPA 2604.
Sony sounded very cool with each. My favourite is Philips with OPA 2604 wich sounds very rich , very warm and very relaxed and natural. The worse is Marantz wich sound very poor, non-dynamic but relaxed. In Marantz the best was OPA 2134.
Every opamp have his own sound. It depends of what you prefer. Here is not good or bad, just what you like or don't.
I guess it matters a lot if the stage was the I/V converter (if that DAC required one, some have voltage output) or just the analog filter following that.
I had a good experience with LM4562 in place of some LM833 in the filter and I/V stage. I had tried some NJM2068 too, but I like it better with 4562.
As a side note - the board needs to be cleand really good!
BTW, what did you had originally there?
I had a good experience with LM4562 in place of some LM833 in the filter and I/V stage. I had tried some NJM2068 too, but I like it better with 4562.
As a side note - the board needs to be cleand really good!
BTW, what did you had originally there?
Yes, you have right. But it was just a very quick tweak.
In Sony CDP950 was 2X JRC 5532
In Philips CD930 was 2X LM833
Marantz CD48 was 1X JRC 4560