Hifi Preamps for your Record Player

By: skrodahl | July 16, 2018

I just got a request from someone who wants to CNC a front panel for his Muffsy MC Head Amp, and he wanted to use the logo and the font that are on the printed circuit boards.

OSIFONT - The CAD Font

The font used on the PCB is the built-in vector font in Eagle, which is proprietary. The Eagle font is really similar to the "official" CAD font OSIFONT. Which is, I'm sorry to say, proprietary.


Luckily, Github user hikikomori82 has made an open source variant of OSIFONT:

The "Muffsyfont" - The OSIFONT to a T

I thought the lower case "t" looked wrong, so I changed it, and now it's the Muffsyfont.


Download the Muffsyfont here.

Muffsy Logo and text using the modified hikikomori82's OSIFONT

And Finally the Logo

The logo is a bit easier though, I can share that with anyone. And by virtue of placing it on this site, it becomes open source as well.

By: skrodahl | June 15, 2018

It's become evident that I need a better solution for photographing my projects. So I went out and bought some surprisingly cheap LED panels:

LED Panel
LED panel, (c) MIA Worldlight

But then I had no idea on how to build this into a suitable light box. So I spent the time buying suitably sized vinyl backdrops and some clamps from the UK based eBay seller photogeeks11. I can't thank the seller enough, small sized vinyl backdrops are very hard to find. They are also of excellent quality.

 
Black backdrop
Black backdrop, (c) photogeeks11
 
Mini clamps
Mini clamps, (c) photogeeks11
 
White backdrop
White backdrop, (c) photogeeks11

My first lightbox...

The first lightbox was three pieces of scrapped wooden planks. Just to hang the backdrops from. The two side LED panels leaned against the planks, and I managed to somehow balance the top LED panel long enough to take one picture. Then it all crumbled and fell to the floor. (Nothing broke, luckily.)

My first lightbox
My first lightbox

It did produce one good picture before the whole construction fell apart though. Keep in mind that this is taken using my Galaxy S7 Edge with default settings.

My first lightbox picture
My first lightbox picture

Rethinking the lightbox (the one that didn't fall apart)

Since I wasn't in the mood for having my (albeit cheap) LED panels crushed, I set out looking for alternatives to scrap wood. I finally found some nice square aluminum tubing and plastic joints.

 
 
 

With the building material in playce, I brought out my trusty old (and very dull) hacksaw and started construction. Here's the result:

 
Second lightbox, partly assembled
Second lightbox, partly assembled
 
Second lightbox, fully assembled
Second lightbox, fully assembled

The plastic joints had to be hammered into the tubing, and I was a bit worried that I would never be able to disassemble the light box (it's big, and I don't have that much space). Luckily, the plastic sort of shaved off. Using the hammer, I was able to take it apart.


While still a very snug fit - which is good, the lightbox is nice and stable - I'm able to pull the tubes apart so I can store the lightbox when it's not in use.

Pictures, or it didn't happen!

Well, I have only one picture. It's of my B&O IcePower module, on white vinyl backdrop.


This picture is also taken with my Galaxy S7 (the system camera is now on a tripod in front of the light box). I had to change exposure, and do some post-editing though. 

IcePower 125asx2
IcePower 125asx2

I think that's quite a beautiful result. Now that I have the system camera mounted, I've finally found my lightbox solution.


It wasn't exactly cheap though, it came in at just above US$ 300. It's tailor made to my needs, which is why we all do the DIY-thingie in the first place. Right?

Update: Picture taken with the system camera

Here's the Muffsy Back Panel photographed with my Sony Alpha 5000 with a Minolta MD Rokkor 50mm f/1.7:

...and the camera itself:

The Sony Alpha 5000, with its 20 megapixel APS-C sensor, is really great as a manual camera. It's got no viewfinder or fancy autofocus, so I wouldn't use it to shoot sports pics. Or outdoors, due to the relatively dim LCD monitor...


The range of vintage lenses that can be used with the Sony Alpha (E-mount) cameras is almost endless, since there are adapters available for most lenses. Check out the YouTube channel AdaptedAlpha to see lots of examples of older lenses being used with the Sony E-mount cameras.

By: skrodahl | May 03, 2016

Ryan has built the Muffsy Phono Preamp, and wrote about it on his blog. Thanks for the great review Ryan!


He offers up some beautiful pictures of his build, and writes about the whole building experience.

Ryan was one of the few who received power supply capacitors that were too big for the board. That problem was solved, but it's a sub-par experience for those who got them nonetheless.


He also notes, like many others, that it can be difficult to insert the cables into the screw terminals. This is a side effect of making everything fit on the small board. You'll find suggestions on how to make this easier in the build instructions if you're worried about this.


Ryan decided to make his own back panel, and the final result is excellent.

By: skrodahl | January 27, 2016

Yngve from Norway has built a total of five Muffsy Phono Preamps by now, but this has to be his coolest project ever. When he bought a Dual 1225, he decided to give it an integrated phono stage, using the Muffsy.

Muffsy compared to the Dual 1225

The Dual 1225 was opened, the drill was brought out, and the Muffsy placement was decided.

Muffsy mounted inside the plinth

Next is the cabling, Ynge decided to connect the tone arm cables directly to the Muffsy input.

Cabling in progress
Tone arm cables

There was even space for a power supply and a transformer inside the Dual 1225.


Yngve reports that he's very happy with his upgraded Dual. There is absolutely no noise or any distortions, so he has succeeded with his well thought out layout.

Power supply mounted inside the Dual 1225

By: skrodahl | November 10, 2015

Ivo, who created the SMD version of the Muffsy Phono Preamp, has sent me a lot of nice pictures and a description of his project.

Ivo's SMDMuffsy - PCB

Here's what Ivo says about his project:


I wanted to build a compact turntable preamp with some adjusting capabilities such as gain, impedance and input  capacitance . So I found the Muffsy PP-3 as a very good and valid starting point for my build project. 


At the same time i wanted to do something rare in a audiophile world and SMD seems to be rare. Using SMD components allow to reduce the size of the board. The smaller the size of the components and PCB, the lower the possible external interferences. So I decided to try to build this project with SMD components.

Ivo's SMDMuffsy - Populated

It was very hard selecting the components, and the cost increase for a single board is high. For my PP I chose all resistors in 1206 package and 1% tolerance, and all the capacitors in 1206 package and 5% for the capacitors (excluding the RIAA and the output capacitors).


The RIAA eq network capacitors are high quality KEMET PPS capacitors (case 1210 and 1812 5%) and the output capacitors are PET capacitors from WIMA (10% tolerance, case 2824). I also put some attention to keep the signal path as short as possible and equal length between left and right channels.

Ivo's SMDMuffsy in the Enclosure

I decided to build the PP and the PSU on the same PCB, but leaving them disconnected and connect the two circuits by wire. The boards can then be separated, if needed.The final dimensions for the PCB (PP + PSU) is about 12cm x 9cm and it fits exactly in a B1304 enclosure.

Ivo's SMDMuffsy - Close-Up

At this time i can only measure the noise and I got:
  • Power ripple/noise: 12mVpp, 0.166mV RMS
  • Output noise with shorted input: 7.12mVpp, 0.173mV RMS

Ivo's Front Panel

That's the project in Ivo's own words. He has been very focused, with a clear design goal from the start. The end result has become very nice because of this.


I particularly like how he mounted the LED in the front panel. This nice effect came from drilling about 80% through with a 5mm drill, and finishing with a 2mm drill. The remaining hole was filled with hot glue and polished.


It was great to be able to support Ivo in this project, and I am very happy for him that everything worked out as he wanted it to.

Category: Pictures 

Tags: muffsy, phonostage, vinyl, ivo, smd 

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