In your case it wasn't the value of R2 per se., but the fact that you set the gain of the first stage so low, which reduces the S/N, particularly in the lower frequencies. The whole circuit works most efficiently configured for a gain of 60 dB or more.
he won't get far on foot!
If I wanted to power a clone and a VMPS? (MM pre) from a single power supply, would that have any downside and would the standard clone transformer and bridges suffice.
If bigger is better, how big?
And, no-I don't want another switch to throw!
If I wanted to power a clone and a VMPS? (MM pre) from a single power supply, would that have any downside and would the standard clone transformer and bridges suffice.
If bigger is better, how big?
And, no-I don't want another switch to throw!
I've done it. Used both at the same time as I have 2 arms on my TT and swithched the preamp between the two (VSPS & Phonoclone). I have a single 80 VA Tx and another with a 50 Va both with dual outputs. Can't tell the difference really. Works fine.
I normally power the Sapphire with the second plug though.
kffern
We interrupt the regularly scheduled help desk discussion for a special announcement about kit availability.
Phonoclone Kit : $125 (10 availble) Set of two boards and components to populate.
VSPS 300 Kit : $117 (10 available) Set of two boards and components to populate.
Sapphire Kit : $113 (10 available) Set of two boards and components to populate.
Thank you. As you were. 🙂
Phonoclone Kit : $125 (10 availble) Set of two boards and components to populate.
VSPS 300 Kit : $117 (10 available) Set of two boards and components to populate.
Sapphire Kit : $113 (10 available) Set of two boards and components to populate.
Thank you. As you were. 🙂
what size are VSPS 300 boards?
Are they the same dimensions as Phonoclone single channel boards w/X rgl?
If not, what are the dimension?
Regards, Phil
Are they the same dimensions as Phonoclone single channel boards w/X rgl?
If not, what are the dimension?
Regards, Phil
Phonoclone 3 and VSPS 300 are the same size and share the same mounting holes. Swap them out, swap them in.
op am rolling blues
Hi RJM, I build a phonoclone 3 and all is good, great sound, however, I decided to do a little opamp rolling, tried opa 134s, this results in the sound being all broken up (oscillation?) so I reverted to the pa27s back to normal.
Your thoughts please, I was under the impression that they would be compatible.
Thanks in advance.
Hi RJM, I build a phonoclone 3 and all is good, great sound, however, I decided to do a little opamp rolling, tried opa 134s, this results in the sound being all broken up (oscillation?) so I reverted to the pa27s back to normal.
Your thoughts please, I was under the impression that they would be compatible.
Thanks in advance.
That's strange as I know someone who tried the OPA134's and thought they sounded better than the OPA27GP's.
While the OPA27 is the best choice, probably, for the Phonoclone circuit, I would have expected something like the OPA134 to be at least stable.
No obvious reason that it should oscillate, but I have not tried it myself.
No obvious reason that it should oscillate, but I have not tried it myself.
op am rolling blues
Thanks for the replies, looking at my power supply at the moment and it was a bit shonky, as my old tranformers were recycled and only just good enough to get me up and running, I just bought a new 160 va toroid so I am rethinking my build.
It has been mentioned in previous posts that the op amps for the Xreg work don't like regulated voltage, however, would additional capacitance (4700) uf or so per rail between the phonoclone board and the rectifiers benefit the operation of the Xreg or is the onboard capacitance optimal for what is required? (I am from the school of more is better).
Thanks
Thanks for the replies, looking at my power supply at the moment and it was a bit shonky, as my old tranformers were recycled and only just good enough to get me up and running, I just bought a new 160 va toroid so I am rethinking my build.
It has been mentioned in previous posts that the op amps for the Xreg work don't like regulated voltage, however, would additional capacitance (4700) uf or so per rail between the phonoclone board and the rectifiers benefit the operation of the Xreg or is the onboard capacitance optimal for what is required? (I am from the school of more is better).
Thanks
There is already 1000 uF on board, and there is ~no ripple present on the phonoclone output above the noise floor. It was chosen to be sufficient and I don't see any benefit of additional filter capacitance.
I dislike using large filter caps, the diode conduct for such a short time, the average current during the charging cycle skyrockets...
I dislike using large filter caps, the diode conduct for such a short time, the average current during the charging cycle skyrockets...
I just bought the phonoclone kit.
I assume that I need to supply the chassis, power transformer, connectors, wire, and mounting hardware.
I also assume that I need to do the calculations for my cartridge (the Clearaudio MC that comes with the Concept table) and get the appropriate parts to match.
Is that it?
Thanks. I am excited to start the project.
I assume that I need to supply the chassis, power transformer, connectors, wire, and mounting hardware.
I also assume that I need to do the calculations for my cartridge (the Clearaudio MC that comes with the Concept table) and get the appropriate parts to match.
Is that it?
Thanks. I am excited to start the project.
I am going to try to order a Phonoclone kit (if any are left).
My power supply thoughts were to use one large transformer (say 225 - 300va) and then run separate bridge rectifier boards (Per Anders) and separate L+R cords to the Phonoclone enclosure.
Is there any advantage (crosstalk etc) in using two smaller transformers?
I will be using the Phonoclone with a Project Perspective turntable and a rebodied Denon 103 Pro Cartridge.
My power supply thoughts were to use one large transformer (say 225 - 300va) and then run separate bridge rectifier boards (Per Anders) and separate L+R cords to the Phonoclone enclosure.
Is there any advantage (crosstalk etc) in using two smaller transformers?
I will be using the Phonoclone with a Project Perspective turntable and a rebodied Denon 103 Pro Cartridge.
Hi guys,
Sold through the Phonoclone Kits already. No more until, well, later - fall perhaps. Still have a few VSPS300 and VSPS though.
re. power supply, a single 25 VA transformer and rectifiers are all you need. There is filter capacitance and sophisticated voltage regulation already included on the main boards.
You can use two small transformer, or one larger one. Advantages to either route are going to be in the realm of personal preference. Hard to say which gives more benefit.
/R
Sold through the Phonoclone Kits already. No more until, well, later - fall perhaps. Still have a few VSPS300 and VSPS though.
re. power supply, a single 25 VA transformer and rectifiers are all you need. There is filter capacitance and sophisticated voltage regulation already included on the main boards.
You can use two small transformer, or one larger one. Advantages to either route are going to be in the realm of personal preference. Hard to say which gives more benefit.
/R
300VA? all you need is 30/50VA. I used two 30VA in separate cases. No problems, and they are more than enough.
Thanks for the replies, looks like I am too late for the last batch of Phonoclone kits.
Looking back through the thread I did see some comments about more "bass slam/impact" with higher VA and I used to have Naim amps many years ago before going down the DIY path, where the high VA "HiCap' supplies were an upgrade in their preamps.
I gather then that there is no sonic advantage in using 2 transformers.
Looking back through the thread I did see some comments about more "bass slam/impact" with higher VA and I used to have Naim amps many years ago before going down the DIY path, where the high VA "HiCap' supplies were an upgrade in their preamps.
I gather then that there is no sonic advantage in using 2 transformers.
There are advantages to either 2 transformers (soundstage) or a larger transformer (bass impact) ... but they are not that significant and there are downsides re. cost, size, weight, and, for a very large transformer, physical hum. A 25 VA (or two) is sufficient. That's the point I wanted to get across.
Hi Folks, Well Ive been lurking on this thread for awhile and decided to build it. I read the whole thread and the other one here and at karma (do I get an attaboy?) it took a week of evenings. I think I might of got the last kit. I was thinking of going dual mono on the PS and using a 50va TE62082 for each channel. Is this silly? I already have the traffos. I like to operate on the "a job worth doin is worth overdoin" principle. As soon as the parts arrive Im ready to build, Ill post my results.
Um, the thread is just a record of the back and forth of the project, over several years now. It's not required reading before building the kit! The instructions included + the web pages are really all you need...
50va TE62082 is ideal. Two, even better. They hardly cost any more than the 35VA model, and are nice and small.
50va TE62082 is ideal. Two, even better. They hardly cost any more than the 35VA model, and are nice and small.