Handmade Passive Preamplifier at very First Time

[AudioLover525 6]

Hello all! Just new to the forum and would like to share my very first handmade passive preamp!

Lots of fun to make it successfully amplifying and tuning sound quality in thick bass or accurate positioning  Attached below with some images about the attenuator, transformer, casework etc., you guys may also take a look at the schematic for the whole circuit. Those attenuator and transformer are handcrafted and manufactured from my hometown Hong Kong, which I really appreciate the sound quality and technology applied. 

I am looking forward to discussing my work with all of you! Feel free to ask me anything about it.  If you guys are interested you could search them on Google on your own..

Schematic.pdf

Edited November 21, 2020 by AudioLover525

[BruceFlea 182]

Looks a pretty impressive build!

[John (big) 47]

Way more than my skill set impressive

[awkwardbydesign 1,022]

Very nice.  Details of the components would be appreciated, plus any links to suppliers.  Particularly the case.

I have used transformers from Promitheus, which gave a 6dB gain, but never needed it, as my sources had enough gain.

Edited November 18, 2020 by awkwardbydesign

[bencat 2,292]

Agree a few details about the components including prices is always useful. This looks way beyond my  abilities but how hard and fiddly is the soldering?

[dave 294]

http://www.designbymrk.com/

Seems to sell by ebay, 

[MF 1000 1,641]

So ‘handmade’ but not an amateur then ....

[AudioLover525 6]

On 18/11/2020 at 18:22, awkwardbydesign said:

Very nice.  Details of the components would be appreciated, plus any links to suppliers.  Particularly the case.

I have used transformers from Promitheus, which gave a 6dB gain, but never needed it, as my sources had enough gain.

Thank you so much!

Here I use a 59 steps autotransformer for voltage amplifying. Magnetic force is induced throughout this C Core transformer, with 1X, 3X, 5X and 10X gain options, sound qualities could vary from sweet to thick bass to super thick...There is no need to use any power sources, meaning no active components or power line/supplies or wall plug are used, so no noise and distortion will be added to the passive preamp.  Plus, a 59 steps mechanical volume switch is used(really not an electronic one!) which makes me feel concrete and great during tuning!

For the casework, I just bought it.

I see for your another transformer. For mine you are able to select four options of gain, up to 10 times(+20dB), but since you don't think you need such a high gain, you could select other lower gain options freely here!

Edited November 21, 2020 by AudioLover525

[AudioLover525 6]

On 18/11/2020 at 20:06, bencat said:

Agree a few details about the components including prices is always useful. This looks way beyond my  abilities but how hard and fiddly is the soldering?

Sure and I quoted what I've just replied for the component details:

"Here I use a 59 steps autotransformer for voltage amplifying. Magnetic force is induced throughout this C Core transformer, with 1X, 3X, 5X and 10X gain options, sound qualities could vary from sweet to thick bass to super thick...There is no need to use any power sources, meaning no active components or power line/supplies or wall plug are used, so no noise and distortion will be added to the passive preamp.  Plus, a 59 steps mechanical volume switch is used(really not an electronic one!) which makes me feel concrete and great during tuning!" 

Don't worry about the soldering as it will be made already for the component product.

Edited November 21, 2020 by AudioLover525

[AudioLover525 6]

On 18/11/2020 at 20:17, dave said:

http://www.designbymrk.com/

Seems to sell by ebay, 

Yes! That's so good that you could find them on your own! But since it involves advertising perhaps you needa delete the information. Thanks!

Edited November 21, 2020 by AudioLover525

[John (big) 47]

I don't feel so inadequate now.  Seems a professional job... 

[George 47 2,256]

You clearly are a dealer and as a dealer you must be registered as a dealer and pay the appropriate dealer's fees. Otherwise, the 'advert' will be removed. It would also be helpful to state where you are based so anyone interested in buying a preamp will know where in the world you are based. Thank you.

[wizmax 381]

13 minutes ago, George 47 said:

You clearly are a dealer and as a dealer you must be registered as a dealer and pay the appropriate dealer's fees. Otherwise, the 'advert' will be removed. It would also be helpful to state where you are based so anyone interested in buying a preamp will know where in the world you are based. Thank you.

Says his hometown is Hong Kong in the description.

[AudioLover525 6]

18 hours ago, George 47 said:

You clearly are a dealer and as a dealer you must be registered as a dealer and pay the appropriate dealer's fees. Otherwise, the 'advert' will be removed. It would also be helpful to state where you are based so anyone interested in buying a preamp will know where in the world you are based. Thank you.

Apologized for the rules violation problem. I will delete all descriptions with the brand name. 

Yes, I am based in Hong Kong but I am not a dealer as described. Somebody posted the link directly but not me.

Edited November 21, 2020 by AudioLover525

[AudioLover525 6]

19 hours ago, John (big) said:

I don't feel so inadequate now.  Seems a professional job... 

Thanks John! This one really made by my own.