Batery powered DIY CNC phono stage

[sachu888]

Even Sachin doesn't know so this must be a tough one:lol:

Hi,
This wasn't tough one,I am running my cart on 33k and 62k ,but since this question was asked first time ,so wanted to be sure

Regards,
Sachin

 

[tek]

How often do we need to change batteries on the CNC Phono stage? Will you be able to tell once the red LED becomes dimmer, or by deterioration in sound? Changing batteries on a weekly or bi-weekly basis could prove to be an expensive proposition!

Sachu, have you noticed a lessening with sound quality or have you already changed the batteries?
I am currently using Duracel 9V batteries..

 

[sachu888]

How often do we need to change batteries on the CNC Phono stage? Will you be able to tell once the red LED becomes dimmer, or by deterioration in sound? Changing batteries on a weekly or bi-weekly basis could prove to be an expensive proposition!

Sachu, have you noticed a lessening with sound quality or have you already changed the batteries?
I am currently using Duracel 9V batteries..

Hi Tek,
I have not put any LED so can't comment.I have changed my batteries once after about 40 hrs of playing time.There are some duplicate Duracell batteries which will not last that long,please ensure before buying.I am planning to use 4 of these Lantern batteries(2 batteries per side, which will give +/-12V and last min 2 years
ENERGIZER|1209|BATTERY, 6V, BLACK, LANTERN | element14 India
EVER READY|PJ996|BATTERY, PJ996, 6V | element14 India
This can be run on well filtered power supply like Ellot sound product/Bugle power supply
Power Supply for Preamps
but power supplies could introduce some noise,so batteries for me.
Regards,
Sachin

 

[bhaskarcan]

Hi Sachin,

What about these 12volt 7Ah rechargeable UPS batteries?

Thanks & Brgds

Bhaskar

 

[quad]

What about these 12volt 7Ah rechargeable UPS batteries?

Bhaskar

They should work fine. You will need two of them, of course.
And some kind of external charger.

 

[sachu888]

Hi Sachin,

What about these 12volt 7Ah rechargeable UPS batteries?

Thanks & Brgds

Bhaskar

Hi, this can be a good option,Few Ak members are also running on these.You will need two of these to get +/-12V.That could be little costly.If you buy 4 Lantern batteries of 6V they can power CNC to 2-3 years with +/-12V.My 9v batteries last 40hrs+.

Regards,
Sachin

 

[omishra]

Re: Battery powered DIY CNC phono stage

.My 9v batteries last 40hrs+

That is because you did not use that LED.

@tek: if you are okay with switching on-off without LED indicator then cut one leg of LED (near red wire) at power ON switch. This will save few hrs of costly battery life.

 

[jls001]

Re: Battery powered DIY CNC phono stage

This will save few hrs of costly battery life.

Why not rechargeable batteries like Camelion, Sanyo, etc? 1.2v x 10 nos = 12V (these rechargeables are rated 1.2V and not 1.5V). And something like a 2100 mAH rating should have significant playing time. I think these type of batteries are no longer so much costly (jjmehta.com eShop)

Quick and Dirty DIY solution: roll up all the cells in paper so that the terminals are in tight contact. Rig up wires at + and - ends and connect to CNC phono stage.

 

[sachu888]

Re: Battery powered DIY CNC phono stage

Why not rechargeable batteries like Camelion, Sanyo, etc? 1.2v x 10 nos = 12V (these rechargeables are rated 1.2V and not 1.5V). And something like a 2100 mAH rating should have significant playing time. I think these type of batteries are no longer so much costly (jjmehta.com eShop)

Quick and Dirty DIY solution: roll up all the cells in paper so that the terminals are in tight contact. Rig up wires at + and - ends and connect to CNC phono stage.

Good suggestion,but 10 batteries will give only +/- 6V.Using two 6v lantern batteries per side will provide +/-12V and should last minimum 2 years with average playing time of 2hrs/day,so they are cost effective.

Regards,
Sachin

 

[bhaskarcan]

Hi all,

Finally I got my CNC PS up & running. Agree with other FM's here & in AK regarding SQ. Currently using 33kohms setting for Shure97xe. Awaiting 30hrs break in for final verdict.

Thanks everybody(specially Sachin, Omishra & Quad) for their valuable inputs in this project.

Brgds,

Bhaskar

 

[sachu888]

Hi all,

Finally I got my CNC PS up & running. Agree with other FM's here & in AK regarding SQ. Currently using 33kohms setting for Shure97xe. Awaiting 30hrs break in for final verdict.

Thanks everybody(specially Shachin, Omishra & Quad) for their valuable inputs in this project.

Brgds,

Bhaskar

Hi Bhaskar,
Nice innovative case,Some people find 62k setting best for M97xe,your ears are best judge.

Regards,
Sachin

 

[omishra]

Hi all,

Finally I got my CNC PS up & running. Agree with other FM's here & in AK regarding SQ. Currently using 33kohms setting for Shure97xe. Awaiting 30hrs break in for final verdict.

Thanks everybody(specially Shachin, Omishra & Quad) for their valuable inputs in this project.

Brgds,

Bhaskar

This is nicely executed.

 

[bhaskarcan]

Hi Sachin,

I somewhat tried all 4 settings. The CNC PS is attached to the Sansui amp which has got nice attack & is not very mellow as my Sony 333esx amp. In my case with 47k & 62k settings the HF sounded little harsh(may be I'm still habituated of the 'Sony sound'). So I set it to 33k which IMO complements the Sansui sound. But it's all too early for any final setting. Let it break in & then I can decide. Meanwhile I can continue experimenting with different settings.

Thanks & Brgds,

Bhaskar

 

[sachu888]

Hi Sachin,

I somewhat tried all 4 settings. The CNC PS is attached to the Sansui amp which has got nice attack & is not very mellow as my Sony 333esx amp. In my case with 47k & 62k settings the HF sounded little harsh(may be I'm still habituated of the 'Sony sound'). So I set it to 33k which IMO complements the Sansui sound. But it's all too early for any final setting. Let it break in & then I can decide. Meanwhile I can continue experimenting with different settings.

Thanks & Brgds,

Bhaskar

Hi Bhaskar,
Impedance settings can be personal,so may be 33k works best for you.I never had any M97xe so can't comment,but it should not distort in HF,either your cartridge alignment is off or stylus is dirty.CNC is very sensitive, and small amount of gunk on stylus can cause distortion.
PS: You own some very good vintage equipments:clapping:

Regards,
Sachin

 

[bhaskarcan]

Hi Sachin,

I didn't mean distorted HF, only little harsh for my taste. At 33k that harshness is no more there.

Thanks & Brgds,

Bhaskar

 

[sachu888]

Hi Sachin,

I didn't mean distorted HF, only little harsh for my taste. At 33k that harshnesh is no more there.

Thanks & Brgds,

Bhaskar

Hi Bhaskar,
Sorry I read it wrong

Regards,
Sachin

 

[bhaskarcan]

Hi All,

Anybody completed 30hrs burn-in time for this baby(I've only ~12 hours)? Any review/comparison with any of the "Audiofool" grade phono-stages? Impedence settings....? Remarks.........?

Thanks & Brgds,

Bhaskar

 

[sachu888]

Hi All,

Anybody completed 30hrs burn-in time for this baby(I've only ~12 hours)? Any review/comparison with any of the "Audiofool" grade phono-stages? Impedence settings....? Remarks.........?

Thanks & Brgds,

Bhaskar

Hi Bhaskar,
I have completed 30hrs on my CNC and it is super quite,surface noice is very low,dead silent between tracks,very detailed,wide soundstage,very good bass etc.I have heard some good phonostages and this beats all.I am quoting some AK reviews here:

"I finished my CNC last night after a few setbacks. While desoldering a wire, using a solder-sucker, a pad lifted off the PCB. I was so pissed and depressed that I shelved the project for a few days to let myself cool down. I PM'ed with HypnoToad and he walked me through a fix, and it worked. It's not perfect, but the workaround is stable and I now have a functioning CNC! I have a Sansui 5000x that was recapped/updated by Avionic and it has a really nice phono stage. The CNC just blows that out of the water. Super crisp, dead quiet and a lush soundstage. I only had a while to play with it last night but I look forward to diving in tonight (and rolling opamps soon). Thanks again to Fasterdamnit, Big Bill and HypnoToad for all your patience, support and inspiration."- Dodog

"I heard Fasterdamnit's CNC Saturday night in my system, with my cart/arm/table. I know a few guys who HAVE to have one of these, me included.
I cobbled an RIAA preamp together with Op-Amps over 30 years ago and it wasn't pretty sounding. Looking at the specs on today's Op-Amps I'll attribute the huge improvement in sound to at least a couple of specs that have really improved. The slew rate is now insane. The gain bandwidth product is even greater extending to RF.
Not to mention the noise is imperceptible. This is one quiet preamp. Just amazing.
BTW, I'm planning on SLA 12V batteries that I recharge."- Grainger49

"I then did another comparison between the "CNC" and the P06 expecting them to be nearly identical.

I was wrong it is the P06 that is now slightly on the grainy side compared with the "CNC". The sound stage is extremely wide and 3d with as much detail as I have heard mixed with a ever so slightly mellow sound that is very pleasing to the ear. Exactly what the AD823's should ultimately sound like or even what the venerable OPA627/637's are described as.

Who's the idiot that put those loading resistors in the first place? It seems they don't agree with the output of the op amps."- Hypnotoad

There are some more reviews on AK.One Ak member has sold his Rolls - Bellari VP130 Tube Phono Pre after building CNC.

Regards,
Sachin

 

[reubensm]

Hi, I myself was a hardcore DIY guy in my younger days and am on the look out for doing a worthwhile project. Recently, I got hold of a lovely NAD C320 amp (thanks to Blasto) and am thinking about building a phono stage for it. The NAD3020 or NAD106 phono stages are high on the list but was wondering if it would be worthwhile giving the CNC phono preamp a try. Can anyone share the schematic with me (if its not a problem). Would like to take a serious look as the user comments are outstanding for a DIY preamp. Thanks in advance.

 

[sachu888]

Hi, I myself was a hardcore DIY guy in my younger days and am on the look out for doing a worthwhile project. Recently, I got hold of a lovely NAD C320 amp (thanks to Blasto) and am thinking about building a phono stage for it. The NAD3020 or NAD106 phono stages are high on the list but was wondering if it would be worthwhile giving the CNC phono preamp a try. Can anyone share the schematic with me (if its not a problem). Would like to take a serious look as the user comments are outstanding for a DIY preamp. Thanks in advance.

Hi,
I can send you PCB if you want.Believe me its better than NAD phonos.People have compared it with many expensive phono stages and it sounded better.If you can PM your email address I will send you the PCB file.

Regards,
Sachin