RIAA Pacific rookie attempt

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Sonicraft in the US has some good deals on REL caps and other stuff...

Also, a good place to pick up PRP resistors which I use in my amps and preamps and have been happy with. They won't have all the values for your phono preamp though.

Sonic Craft Specials

Nice guys, I don't know if the shipping form the US would make it worth it though.

If they offer me a cheap shipping i would love to buy the PRP resistors!
 
I wouldnt drop too much money on caps for the Boozehound. Not that it is not good but there are lots of designs out there to play with, especially if you are running a MC cartridge. I like the boozehound a lot, it's the best phono stage I've had but I bet a Pass Pearl sounds better for a JFET stage. Always trust Nelson.

The Pass Pearl, the phonoclone, VSPS and the CNC phono stage all get a lot of action here on the forums. Take a look at those too.

And actually, the BHL kit at $90 is not a bad deal when you consider the cost of jfets and all the caps. It may be cheaper than scratch building it.
 
I wouldnt drop too much money on caps for the Boozehound. Not that it is not good but there are lots of designs out there to play with, especially if you are running a MC cartridge. I like the boozehound a lot, it's the best phono stage I've had but I bet a Pass Pearl sounds better for a JFET stage. Always trust Nelson.

The Pass Pearl, the phonoclone, VSPS and the CNC phono stage all get a lot of action here on the forums. Take a look at those too.

And actually, the BHL kit at $90 is not a bad deal when you consider the cost of jfets and all the caps. It may be cheaper than scratch building it.

The Pearl looks rather interesting, plus theres already gerber files for it out there.
 
There are two types of power supplies (other than batteries), Switching and linear. Switching supplies are the small "box-type" plastic things that plug in the wall. Adding caps and or filters may make these quieter. But its not really the best solution.

A linear PS consists of a transformer, rectifier and in this case, a regulator. It is more complex to build and requires more parts.

For this preamp, a great solution would be a linear supply with a lm317 regulator or maybe even something more exotic like a shunt reg. It could be better than batteries. I am using batteries which sound good but I'd like to be able to leave my system on all the time so I am investigating linear supplies.

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I definitely recommend using the battery. I made above battery pack include 20pcs 1.2V 2200mA rechargeable Sub-C NiCd battery | eBay 1.2Vx20=24V
I am using this charger for my battery pack: Intelligent Charger for NiMH NiCd 1 2V to 24V Battery Pack by 1 20pcs Cells US | eBay

If you are planning to use 24VDC from a converter and eventually filtering the noise, there is a serious option in my opinion:
1. Transformer (24V Output): Hammond Transformer - More Information Page
Hammond Transformer: Hammond Mfg. - Toroid Power Transformer - (182 Series)
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2. Ultra Low Noise Positive Regulator 2.5V~30V Output High Current Type There is two type: 250mA and 4A: http://www.ebay.com/sch/i.html?_odk...C+Ultra+Low+Noise+Positive+Regulator&_sacat=0

An externally hosted image should be here but it was not working when we last tested it.
 
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I built the boozehound labs phono preamp kit but replaced all resistors and capacitors with matched pairs (L+R) for optimal channel matching. I also used some Russian Teflon caps in the filter and coupling positions, with the remainder Russian K40 paper & oil. I didn't play with different caps, just used the best matched pairs I had in each position.

I added a B1 buffer stage on the output as my preamp necessitates a lower output impedance than the BHL phono pre has alone. This is easy to do and consistent with the overall philosophy of the design (zero feedback 2SK170 stages that can run from the same PSU).

The sound is great and a big step up over the Clearaudio Smart Phono I had before. Much more solid sound with better imaging, more detail but less edge.
 
The IN and OUT traces were very close on the previous design so i remade it a bit. To be honest i wanted to build a SMD version, but is it feasible to source similar component equivalents in SMD as TH?
 

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I definitely recommend using the battery. I made above battery pack include 20pcs 1.2V 2200mA rechargeable Sub-C NiCd battery | eBay 1.2Vx20=24V
I am using this charger for my battery pack: Intelligent Charger for NiMH NiCd 1 2V to 24V Battery Pack by 1 20pcs Cells US | eBay

If you are planning to use 24VDC from a converter and eventually filtering the noise, there is a serious option in my opinion:
1. Transformer (24V Output): Hammond Transformer - More Information Page
Hammond Transformer: Hammond Mfg. - Toroid Power Transformer - (182 Series)
182pic.jpg


2. Ultra Low Noise Positive Regulator 2.5V~30V Output High Current Type There is two type: 250mA and 4A: ULN HC78C Ultra Low Noise Positive Regulator | eBay

An externally hosted image should be here but it was not working when we last tested it.

I prefer direct source rather than the batteries. Perhaps its possible to find a regulator/filter as DIY, since 56$ seems like quite alot?
 
I want to shrink the RIAA down to something smaller and was wondering if this SMD version (resistors) seems insane or feasible? Im worried about noise and hope someone could throw an eye on the design. The SMD resistors are 1206 package.
 

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I like the way you have put your case together, holding the module in place with string. Great DIY :D And the light at the front.. Cool.

tfnt.jpg


0jpw.jpg

I definitely recommend using the battery. I made above battery pack include 20pcs 1.2V 2200mA rechargeable Sub-C NiCd battery | eBay 1.2Vx20=24V
I am using this charger for my battery pack: Intelligent Charger for NiMH NiCd 1 2V to 24V Battery Pack by 1 20pcs Cells US | eBay

If you are planning to use 24VDC from a converter and eventually filtering the noise, there is a serious option in my opinion:
1. Transformer (24V Output): Hammond Transformer - More Information Page
Hammond Transformer: Hammond Mfg. - Toroid Power Transformer - (182 Series)
182pic.jpg


2. Ultra Low Noise Positive Regulator 2.5V~30V Output High Current Type There is two type: 250mA and 4A: ULN HC78C Ultra Low Noise Positive Regulator | eBay

An externally hosted image should be here but it was not working when we last tested it.
 
Coincidentally I've ordered 1x 20V ULN-RD78A from Ebay to power my Boozehound Labs JFET phono and B1 buffer combination. Currently I'm using 2x MC7818CT. I expect delivery in a couple of weeks and will let you know how well it works. I've got efficient Tannoy dual concentrics so should be able to judge changes to the noise floor easily.
 
The super regulator from diyaudio looks interesting aswell. I think it will be either that or the Sjöström. For the sake of logistics i may be tempted to pick Sjöström hence its shipped from Scandinavia..

A simple 317 based reg would work...maybe not the best performance though.

1 5 to 29V DC Adjustable Voltage Regulator Module Board Based on LM317SKU163002 | eBay

A better sounding option would be a shunt reg or a super regulator like this:

Super Regulator V2.2 - Power Supplies and Accessories - Circuit Boards

You would only use the positive side.

I use 16 AA batteries in mine.
 
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