Pre-amp suggestions needed

[tuff]

SYS measurements. Interesting stuff.
https://www.audiosciencereview.com/...-of-schiit-sys-passive-pre-amp-switcher.2335/

 

[haisaikat]

SYS measurements. Interesting stuff.
https://www.audiosciencereview.com/...-of-schiit-sys-passive-pre-amp-switcher.2335/

Indeed, I did an interesting experiment, I tested with same set of songs using each of the following as standalone preamps
1. CA 851C inbuilt digital preamp
2. My existing integrated amp CA 650A inbuilt preamp
3. Schiit SYS

My observation after careful listening was that CA 650A was chopping off dynamics and was making the output a bit subdued in musicality rather than the other ones. Also one of my asks from the beginning have been that the preamp has to have a tone control feature however i realized that when i tried to play around with the treble controls for the tracks where there was abundance of sibilance, i noticed that the resulting different to be not even a half correction. So I decided to retire the CA 650A here, does not mean its poo, if someone hears to it and only it probably the difference would not be felt.

Next up the SYS and the inbuilt digital preamp of 851C became a almost tie, I said almost since to my ears i could not figure out any difference at pleasant volumes. But I am reserving (for now) the SYS to act as Volume control for the TT setup.

The above brings us back to the search for the preamp once again.

So far we have discussed about couple branded pre-amps including the SS DIY one recommended by @sachu888

Any other DIY option anybody wants to recommend?

 

[tuff]

The SYS is great if you need just a volume control as it is NOT a preamp. If the rest of the chain has synergy, you don't need a preamp, imparting it's own signature. So if you have a good sounding phono preamp or DAC, it retains it's signature, which is a good thing imo.

 

[sachu888]

Hi Saikat,
the preamp has been tested by him. It sounds very good as expected. I might start a GB here for Class AB amp and preamp. Here are some pics of Amp and preamp.

Amp

Regards
Sachin

 

[sanjivnayak]

My observation after careful listening was that CA 650A was chopping off dynamics and was making the output a bit subdued in musicality rather than the other ones. Also one of my asks from the beginning have been that the preamp has to have a tone control feature however i realized that when i tried to play around with the treble controls for the tracks where there was abundance of sibilance, i noticed that the resulting different to be not even a half correction. So I decided to retire the CA 650A here, does not mean its poo, if someone hears to it and only it probably the difference would not be felt.

Pls dont give a bad name to your dog before killing him.

 

[haisaikat]

Pls dont give a bad name to your dog before killing him.

It's the opposite, trying to justify the new gear in comparison to the old one ... Ha ha ha ha ha

 

[haisaikat]

The SYS is great if you need just a volume control as it is NOT a preamp. If the rest of the chain has synergy, you don't need a preamp, imparting it's own signature. So if you have a good sounding phono preamp or DAC, it retains it's signature, which is a good thing imo.

One of the main reason I started this thread was to get a device to act as volume control for the analogue chain. The CDP I have does not have analogue inputs and that it's volume control is digital.

For the starting at low budget I do see SYS as the cheap option (@3.5K) with 2 inputs followed by the diy option of @sachu888 (3k + cabinet) followed by the of but good condition CA C500 offered by an FM (9k) ... and and and a Little Dot MK ii with Mullard M8100 and 6H6Pi tubes for 11k (has tube rolling options to a large extent is what I read)

@sachu888, I have the CNC phono, is it's output enough powerful to drive a Poweramp or a preamp is needed? If output is high the sys will do fine for now at lowest cost as volume control

 

[sachu888]

One of the main reason I started this thread was to get a device to act as volume control for the analogue chain. The CDP I have does not have analogue inputs and that it's volume control is digital.

For the starting at low budget I do see SYS as the cheap option (@3.5K) with 2 inputs followed by the diy option of @sachu888 (3k + cabinet) followed by the of but good condition CA C500 offered by an FM (9k) ... and and and a Little Dot MK ii with Mullard M8100 and 6H6Pi tubes for 11k (has tube rolling options to a large extent is what I read)

@sachu888, I have the CNC phono, is it's output enough powerful to drive a Poweramp or a preamp is needed? If output is high the sys will do fine for now at lowest cost as volume control

CNC has enough gain approx 40db like any other MM phonostage. I think you won't need preamp for additional gain.

Regards
Sachin

 

[haisaikat]

FM Aniket has designed a very good Class A preamp, using all discrete components. It has onboard power supply and volume pot, so it can be directly mounted on faceplate.
Here is a PCB

We have all parts. The approx cost of preamp module would be Rs 3000. He has also designed a 75W Class AB power amp. We may offer few full soldered modules for the same.

Regards
Sachin

Hi Saikat,
the preamp has been tested by him. It sounds very good as expected. I might start a GB here for Class AB amp and preamp. Here are some pics of Amp and preamp.

Amp

Regards
Sachin

@sachu888 can the preamp be equipped with 4 selectable inputs (a relay based option or pole switch for complete separation if that's better), 2 outputs ( 1 for sub in future if I want to use ever) with a gain bypass option for using as only passive volume control and the volume pot be replaced with a stepped attenuator (I mean the ones that do not have the risks of channel imbalany that I am reading can happen with pots)?

And i can request @sadik to make a cabinet once again, if he agrees of course

 

[jls001]

CNC has enough gain approx 40db like any other MM phonostage. I think you won't need preamp for additional gain.

Regards
Sachin

I ran the output of CNC to B1 and later DCB1 buffers - both of which are unity gain - and they worked fine.

 

[haisaikat]

I ran the output of CNC to B1 and later DCB1 buffers - both of which are unity gain - and they worked fine.

Thanks, I need the volume control with selectable inputs but could not say no to diy initiatives of @sachu888 as these are always value so preamp gain would certainly be nice to have.

 

[jls001]

For source selection I prefer simple pot type selectors over relay based boards (both are equally good, IMO), but wiring up pot type selectors can become fairly complex if number of sources are higher. I use 2-pole 4-way. 2-pole supports left and right channels. 4-way supports 4 inputs.

OT: I'm very keen to try out Aniket's new pre, though I'm very happy with my Kuartlotron buffer at the moment. I will check if I have a 18-0-18 1A transformer at home.

 

[manniraj]

Thanks, I need the volume control with selectable inputs but could not say no to diy initiatives of @sachu888 as these are always value so preamp gain would certainly be nice to have.

Hi

I have the glassware store 3 input selector switch unused. Here is the link to the same. We brought this in a group together with 3-4 members may be last year. http://glass-ware.stores.yahoo.net/atandsise.html

PM me if you are interested and I can share you the images and also the exact number of inputs that you can use. My board has independent ground pins so each input has its own grounding and also the output.

thanks

 

[haisaikat]

OT: I'm very keen to try out Aniket's new pre, though I'm very happy with my Kuartlotron buffer at the moment. I will check if I have a 18-0-18 1A transformer at home.

That is where Sadik helped me to get all into one nice cabinet for CNC

 

[sachu888]

@sachu888 can the preamp be equipped with 4 selectable inputs (a relay based option or pole switch for complete separation if that's better), 2 outputs ( 1 for sub in future if I want to use ever) with a gain bypass option for using as only passive volume control and the volume pot be replaced with a stepped attenuator (I mean the ones that do not have the risks of channel imbalany that I am reading can happen with pots)?

And i can request @sadik to make a cabinet once again, if he agrees of course

Aniket has ordered few source selector boards with preamp. You can use whatever type of volume pot with this preamp. You can request Sadik bhai for built it in a cab.

Regards
Sachin

 

[sachu888]

For source selection I prefer simple pot type selectors over relay based boards (both are equally good, IMO), but wiring up pot type selectors can become fairly complex if number of sources are higher. I use 2-pole 4-way. 2-pole supports left and right channels. 4-way supports 4 inputs.

OT: I'm very keen to try out Aniket's new pre, though I'm very happy with my Kuartlotron buffer at the moment. I will check if I have a 18-0-18 1A transformer at home.

Hi Joshua,
I spoke to Aniket yesterday and preferred transformer is 18-0-18 and 0.5A.

Regards
Sachin

 

[manniraj]

Sent you the pics of the John Broskie's simple source selector switch from the glassware store.

 

[Kannan]

@haisaikat since you want a analogue volume control with source selector, don't complicate things. Just get a preamp with multiple input options.
The Little dot has tube only in the buffer stage, It's pre is solid state with a simple volume control and will not serve your purpose.

 

[Maxprocrj]

Seems a good one.

Ifi itube 2

 

[haisaikat]

@haisaikat since you want a analogue volume control with source selector, don't complicate things. Just get a preamp with multiple input options.
The Little dot has tube only in the buffer stage, It's pre is solid state with a simple volume control and will not serve your purpose.

Can you please re check this? It had 4 tubes 2 for power and 2 for driver as the specs say? Single ended push pull