Phono Stage

CT-Boy wrote:Just checked.
Richersounds is the exclusive distributor of Cambridge Audio products in the UK and the CA640P is listed for GBP99.95! VAT not included I presumed. It's around USD180 in the US.
The CA540P is going for GBP59.95.

I think we're better off getting it locally?

If that is the going rates then it makes sense to get it locally unless you are getting it at GBP60. ( as Zeebee managed to source ) ?

cheers

cmboy wrote:

CT-Boy wrote:Mods for an already excellent product? That ought to be great! Buy now and keep it for mods when the 'mullahs' are avail., future upgrade plans.. hmmm sounds good to me!

Factually, most phono stage that comes supplied with a puny wall wart PSU can benefit from a bigger and higher quality PSU. There's a few brand makes that offer upgrade PSU for their phono, applies to outboard DAC's too.
Anyway, I've read one vinyl related forum where there's discussion of modding this CA phono and one enthusiastic DIY'er even traced out the circuitry and posted it there. Oh well, anything's possible to VOID THE WARRANTY!
BTW, one's tools and skill better be of top notch as the CA PCB is a dual layer PCB and NOT EASY to remove the components for modding. The amateur can wreck and destroy this easily. I saw a lot of sloppy and amateurish work done on this CA...sheesh! (even using caps meant for tube gear...worse still!)

CT....

Tend to agree with CM... its a well thought design and the internals of the CA640P are done meticously. Upgraded PSU would enhance the box.

As for me its in its original state. Sonically it sounds better after a few minutes of play.

cheers

As with this CA, yes its an excellent circuit in its own right and at its price point which is likely one reason for excellent reviews. Nevertheless most of these conventional opamp circuit based phono are neither perfect nor best, and thats where people get ideas to mod and optimize it to its limits. I myself did modded two units and they're enjoying it and I know they've stayed with it todate. For the non fussy or not technically able, its probably another God sent outboard phono for the masses.

cmboy, if you're keen to take a look inside the Pipit, i've posted mine for sale with photos of the internals. U can go check it out. Those long bars u see are solid copper rods, meticulously bent by hand that Frankie uses to connect the RCA jacks to the various points of the PCB.

mugenfoo wrote:cmboy, if you're keen to take a look inside the Pipit, i've posted mine for sale with photos of the internals. U can go check it out. Those long bars u see are solid copper rods, meticulously bent by hand that Frankie uses to connect the RCA jacks to the various points of the PCB.

Thanks mugenfoo.. This design and the fundamentals he implemented is very similar to mine. Almost near identical as far as I can see from the pics. I would have preferred if the builder had used screened interconnect wire to the jacks rather than solid rods, save for very short lengths and won't attract external noise. Noise can affect the overall signal to noise ratio especially in such a sensitive stage like this. Another thing, due to a rather big/spacious layout, I'm tending to see a rather long signal path from input to output which again to my own view is not favourable.
Another is the Class A matter. I'm not sure but I'm guessing its was the simplest method of tweaking the opamp to Class A, but in reality if thats the case, it won't be entirely Class A output if into a solid state preamplifier (next stage) but will perform and better match in Class A if its patched to a tube preamp because of natural high impedance at tube input. More about the pros and cons to tweaking opamps to Class A can be found on the internet.
Again, I stand corrected as I've no idea to the actual circuitry. Nevertheless if it all sounds good as reputed, well and good.

cmboy wrote:

mugenfoo wrote:cmboy, if you're keen to take a look inside the Pipit, i've posted mine for sale with photos of the internals. U can go check it out. Those long bars u see are solid copper rods, meticulously bent by hand that Frankie uses to connect the RCA jacks to the various points of the PCB.

Thanks mugenfoo.. This design and the fundamentals he implemented is very similar to mine. Almost near identical as far as I can see from the pics. I would have preferred if the builder had used screened interconnect wire to the jacks rather than solid rods, save for very short lengths and won't attract external noise. Noise can affect the overall signal to noise ratio especially in such a sensitive stage like this. Another thing, due to a rather big/spacious layout, I'm tending to see a rather long signal path from input to output which again to my own view is not favourable. Nevertheless if it all sounds good as reputed, well and good.

Not sure if the photos are hi-res enough, but another interesting note is that at certain carbon resistors, there are some mini-ferrite cores at their legs as well. I asked Frankie about them, and he says its part of the sound-tuning that they are there, and also not glued down but left to sort of rattle abit in its place.

Couldn't get him to divulge the Opamps that he scrubbed the markings off though!


And yes, the Pipit by nature doesn't have an extremely quiet noise floor, but when the music is playing & the added intrinsic groove noises and sparkles, it's really not much of a problem at all.

The ferrites are there to help eliminate noise, if any..thats all.
Its actually a thoughtful tweak and not many phono stages have this as it increases cost and have to be hand installed. Mass production pcb component filling automated machines can't do this.
I can't see everything for sure but guessing most of the resistors are generic 1% metal film types, very commonly used now for lowest noise and most stable characteristics for most solid state source equipment.
I believe this phono can be souped up more but will come at a cost. E.g, alternate power from battery which can improve the performance to another level.

I'm selling my MS-12B...
http://www.hifi4sale.net/audio-video-equipment-for-sale-f1/yaqin-ms-12b-phono-stage-tube-preamplifier-used-t7130.htm

Anybody from this thread interested please PM me I will give you special price but use PM so I know you're from this thread. Thanks

How come you're selling?...going for an upgrade to something else?

My tube amp sounded very good on its own after caps upgrade that MS-12B has become redundant. So I'm selling it

Plus I'm funding for another "bigger" tube amp

arremie wrote:My tube amp sounded very good on its own after caps upgrade that MS-12B has become redundant. So I'm selling it

Plus I'm funding for another "bigger" tube amp

Giving up on CDs and moving to LP as well? Or upgrading to a better CDP?

Not into LP yet. CD is sufficient for me now. Already bought new CDP replacing my Marantz 6003. Now looking for another tube amp

Hi...

Yaqin has released their Tube Phono Stage, Model MS22B using 12AX7B tubes. Given below is the specification :

Input Power

110V-240V AVAILABLE

Tubes

12AX7B × 2

Output Voltages

0.5V (400Hz input)

Output Jacks

One group of gold plated RCA jacks

Input Sensitivity

≤4.0mV (400Hz, 0.5V output)

Signal Noise Ratio

>85dB (A weight)

Distortion

≤0.11%(400Hz input)

Cartridge Suitability

MM (Moving Megnet) cartridge

Supply Voltage

AC115V 60Hz

cheers

wingman wrote:
Yaqin has released their Tube Phono Stage, Model MS22B using 12AX7B tubes.

Hmmm... another China made phono. I can only wonder what circuitry they've implemented based on just one tube per channel. Their previous model was some sort of hybrid circuit. The last time I fooled around with something like this based on same two tubes, it didn't impress me at all. I had high hopes it'll floor my own existing budget phono but it didn't and never could.
I wonder whats the retail price here.

CM...

It's build is similar to the Tube Buffer's version 3. But the internals were not explained or displayed.

May be wrong here to judge but the core build could be from the Tube Buffer circuitry with some tweaks or additional components to suit the vinyl requirement.

Suspect, price wise in MY could be nothing less then RM450.00 ( the tube buffer pricing version 2 ) Could be cheaper against similar Tube Phono stages which are being sold in MY. But acquiring from the WEB could be much cheaper.

Whether its a killer or being killed its going to be a question in everyone's mind.

cheers

There can't be any resemblence to a tube buffer circuit otherwise it'll result with near zero gain. I suspect its just a minor change with hope of some improvement over the previous build, thats about it.
12AX7 isn't exactly the best tube for any phono stage, perhaps because of wide availability and cost in this case.