September 30, 2015

Capital Audiofest 2015 - Volti, Fyssion, and Daedalus Audio Speakers

I attended Capital Audio Fest 2015 in Rockville, Maryland to not only hear the latest and greatest audio equipment, but to connect on a personal level with other enthusiasts. Zynsonix Audio is a small, boutique company where I enjoy what I do, hand-building cables for audiophiles and hopefully sharing an conversation or two about the hobby and what it means to us. There were many others in the same boat attending CAF, their business priorities occasionally taking a back seat to the passion they have for creating truly unique offerings to others around the world. There were many listening rooms in the Hilton, with 50+ vendors being represented.


It's tough to be an aging audiophile! Things that may have impressed you early on in your search for the holy grail in sound reproduction now likely fall flat on your ears. That being said, when you hear something really groundbreaking after decades of listening, you know that device, speaker, headphone, etc. is truly special.

Three rooms truly stood out to me, not only amazing sound, but for other reasons as well.

Volti Audio were in attendance with their splendid Vittora,($25K), a large horn speaker which has a resemblance to a Klipsch La Scala II, however it's much prettier and the internals have a more modern touch. These speakers had a great presence, very refined, slightly warm, and filled the room with beautiful music.

The Volti Audio Vittora

There was also Daedalus Audio with their Poseidon V.2 speakers in solid maple (dove-tailed and everything! Appx. $22K as configured). These speakers were crystal clear and covered the entire spectrum of sound equally well. They were slightly more forward sounding than the Vittora, the treble energy to the enveloping mid-range to solid, well damped bass was perfectly balanced to these ears. Truly an amazing set of speakers.


Daedalus Audio Poseidon V.2 speakers 


And perhaps the most surprising of the bunch was Fyssion Audio. Easily the most entertaining of the rooms, I was greeted by four enthusiastic gentlemen who were eager to present the fruits of their labor. I didn't know what to expect, it was my first time hearing about the company, and the speakers were very unique in appearance. The gentlemen went in order of progression from their first creation, the Profound Round, which is a tubular speaker which is wrapped in leather and sits a top a wooden tripod (very vintage chic, high WAF here guys), to their newer creations, which included the Mighty Mini. The differences between the models were very apparent. JC of Artisan Audio, parent company of Fyssion, mentioned that the Trinity Engine, the branding for their unique design configurations, was based on empirical design (i.e. if it doesn't sound amazing, scrap it and try again until it's just right). Once the right dimensions were discovered, they use a CNC to accurately create the panels for these speakers.

All of these speakers in the lineup were great performers in their own right, however the ones which really blew my mind was the XY 30X30 series (the smallest of which the aforementioned Mighty Mini). They're called 30X30 as the drivers face 30 degrees away in each direction, something I hadn't seen done before. These speakers may look diminutive in size, however the sound-stage they created was worlds better than anything else I had heard. You could stand almost anywhere in the room and still have really nice imaging, these are not speakers where you must be in the center seat with high frequencies at ear level. Not only was the soundstage immense and enveloping, but the sound quality itself was top notch, with crisp, clear tonal quality.

Fyssion had many speakers from it's lineup on display 


I think what's exciting here is that these speakers are small enough that they could fade away into a living room or den with the right finish. The Mighty Mini measuring 8" x 12" x 20" and its bigger brother the XY 30X30-4 measuring 16" x 11" x 26" perform like far larger speakers, Supreme WAF (wife approval factor) and ZERO sacrifice in sound quality. I'd imagine these speakers would be excellent for video game and film enthusiasts too, livening up the experience with enveloping sound.


My personal favorite, the Mighty Mini 


Cost for the Mighty Mini starts at $3,500, quite a bargain compared to the other speakers in attendance. Fyssion earned a best in show award at Capital Audio Fest, so evidently others were equally as impressed. I'd highly encourage you to seek out an audition of the Fyssion offerings, very impressive in my book.


June 11, 2015

Speaker Amp to Headphone Converter Box

With the recent proliferation of low and mid sensitivity planar magnetic headphones from vendors such as Audeze and HiFiMan, it's easy to see why headphone enthusiasts are craving more power. Whether it's get that extra bass oomph and ability to listen at higher volumes with less distortion, having headphone amplifiers with between 1-6 watts is becoming more commonplace.

Since high wattage headphone amps are becoming more and more the norm, some have decided to hook up their headphones directly to the speaker taps. That's totally doable in a number of cases (see the speaker to headphone amp cable here) however there are other situations when this is not recommended, such as with tube amplifiers with output transformers. The output transformers can short if they don't have enough load, causing damage to your equipment.

Headphones also have a higher impedance than speakers, so while common speaker amps have outputs for 4, 8 and 16 ohms, headphones are often somewhere in between 32 and 600 ohms. You'll possibly hear noise on headphones from a speaker amp as they are more sensitive than speakers, which creates an unwanted noise floor. So to get rid of these problems, a small resistor network is necessary to modify the load for your amplifier, and reduce the audible noise.

A resistor for each channel is needed to attenuate the volume so that it is more compatible with headphones and help reduce noise, and additional resistor is needed to reference ground (again for each channel). These resistor values will vary depending on the impedance of your cans.

The project starts with a small Hammond Aluminum case. Hammond is the standard when it comes to small project boxes like this. You can get this in anodized red, blue, black or plain silver. the usual suspects have it: Mouser, Digikey and Angela.

Hammond Black Anodized Case

The first task is to punch the hole for the headphone jack. I'm using a Neutrik locking in this case. This particular build is a single ended (e.g. not a balanced headphone jack with isolated grounds). This is only possible IF AND ONLY IF the amp's left and right ground is shared. This is simple to check with a multimeter.

To punch the hole I'll be using a Greenlee punch. This makes a nice clean opening to install the Neutrik locking plug. These are expensive, so only get one if you plan to get good use out of it.

Pilot hole

Fixing the Greenlee in place


And the punched hole

Next is the task of drilling out and installing the binding posts on the back. I found that a vertical arrangement allowed the panel space to be used most effectively.

Binding post installed on back panel


The panel holding the binding posts is fastened to the case with four screws, and two teflon solder posts are mounted on the base of the unit. These can be found at VT4C. The resistors for this application need to dissipate power, and therefore heat, and they need to be large for that purpose. There are various power resistors out there that fit the bill, sandcast, metal oxide, wirewound, etc., but they can't degrade the sound, so I am using Mills 12 watt non-inductive wirewound resistors as we don't want any induction screwing with the impedance. The Mills are well thought of for good sound quality, so it was an easy choice. I've also used the larger Kiwame 5W carbon film resistors in parallel.


Resistors wired up

For the wiring I chose to use some choice Kimber TCSS copper in Teflon. 


Kimber wiring




The front panel is secured with four screws, and the top aluminum panel is slid back into place. I adorned it with a nice little branding element. 


Speaker Amp to Headphone Converter Box Front

Speaker Amp to Headphone Converter Box Back

UPDATE 2-21-2017: These have been rather popular and Zynsonix is offering these for sale in different configurations. Below is a unit with 4 pin XLR and Cardas binding posts.




And here is a unit with switchable inputs in a larger box.





I hope you enjoyed this post, please contact Zynsonix if you'd like to purchase a unit.


The Fine Print:
The above steps detailing the building of a speaker amp to converter box are for entertainment purposes only and not to be performed under any circumstances. The owner of this blog and all associated parties can not / will not be held responsible if you attempt the process posted and cause physical harm to yourself, your surroundings or your property. Please keep this in mind.

May 5, 2015

Beyerdynamic Balanced Removable 4 Pin Mini XLR Mod

A client recently sent me one of my favorite headphones to modify, a Beyerdynamic DT770. The DT770, DT880, DT900, and similarly the T1, T5p, T70, and T90 are all intuitive to work with and respond well to new cables and mass loading.

Beyerdynamic DT770 - Pro 80 ohm version

This DT770 would be getting a removable cable mod, which includes the installation of a mini XLR in the headphone cup so the cable can easier be removed for transport or to perhaps have separate cables for portable and home use. The DT770 has room for a mini XLR jack on both the left and right cups, however this user preferred the simpler single ear input. Since I was already going through the trouble, I wired the headphone for balanced operation just in case he ever switches over to balanced listening in the future. The great thing about mini XLR jacks is they lock, so no need to worry about them slipping out like a 3.5mm or 2.5mm. Also, TRS connectors can loosen over time, however this is not as likely with the mini XLR connectors.

Below is a look at the interior driver. As you can see, the DT770 driver is unique in that it has a felt and plastic ring encircling the center, which reduces the sound wave reflection inside the cups.

DT770 driver and felt/plastic ring


Because the felt and plastic circle reach the plastic backing of the cups, any added mass damping should be clear of interaction. Below you'll note the Dynamat Xtreme installed is a small circle which is measured to fit neatly inside the cup and not cause any clearance issues with the driver. 


Dynamat Xtreme used as mass loading


Beyerdynamics used to come with a round hole, but it's square now that they've revised the manufacturing to some extent. I carefully increased the size of the hole diameter toward the round side of the cup with a Dremel to prevent the plug from getting in the way of the driver. The hole does not have to be absolutely round as the ridge on the mini XLR plugs will cover minor imperfections. 

Dremeled hole for 4 pin XLR mini jack


A three or four pin mini XLR jack can be used. In this case I used a four pin as I wanted the user to be able to upgrade to balanced down the line if he wanted, but in other cases, a three pin can be used as the ground is wired shared as default. Please note the position of the jack, if it is not close to the rounded edge like this is, the driver will not fit back in. Dremeling down the metal casing of the jack where it meets the driver may help a little bit, but will reduce the integrity of the jack if too much is taken off. 

Nice, clean fit


Wire should be run from one side of the headphone to the other as this is going to be single entry. A twisted pair of Zynsonix Xev silver clad wiring is prepped and sleeved with black polyolefin heatshrink tubing. 

Wire to run from one cup to the other


This can be wired however the user prefers, however I used the XLR standard (pin 1 = left +, pin 2 = left -, pin 3 = right +, pin 4 = right -). 

Wired with Zynsonix Xev silver clad wire


Before re-installation, the driver solder tabs are cleaned of the stock solder.

Solder tabs cleaned of original solder


The new Zynsonix Xev wires are installed using fresh Cardas silver content solder and the felt/plastic cups re-installed. 

Driver wired up and ready


The foam is reseated on top of the drivers and the earpads are reinstalled, so we have a nice clean 4 pin mini XLR input on our Beyerdynamic DT770 now. 

Installation of mini XLR jack complete

And finally we have the finished product featuring some cool colors, in this case rust with a black accent, terminated with a Switchcraft gold plated mini 3.5mm plug and a Neutrik / REAN mini XLR. Now these old Pros are ready for some stylish listening! 



I hope you enjoyed this post, please contact Zynsonix if you have a pair of Beyerdynamics (or any other headphone) that you'd like recabled or modified.

For more full-sized Beyer headphone mods, check out the Beyerdynamic T5p Recable and the DT880 Recable.


The Fine Print:
The above steps detailing the modification and re-cabling of a headphone are for entertainment purposes only and not to be performed under any circumstances. The owner of this blog and all associated parties can not / will not be held responsible if you attempt the process posted and cause physical harm to yourself, your surroundings or your property. Please keep this in mind.

April 29, 2015

Chipamp Dual Mono LM3886 Gainclone Speaker Amp

I'll be dipping my feet in the chip amp waters again. I enjoyed the results of my previous Chipamp.com LM3886 build, so I decided to build another, more serious version. You can visit that post to read a little bit about the history of the chipamp, also known as the Gainclone, based on 47Labs Gaincard topology.

As you are likely aware, DIYers have created chip-based builds using a variety of power opamp or audio opamp chips including National Semiconductor LM1875, LM3875, LM3886, and LM4780. The most popular chips being the LM3886 and LM3875. You'll find a number of these designs at Chipamp Electronics.

This more serious build features a pair of Antek 300VA torroids, each with their own shield, integrated amp functionality with an Alps Blue Velvet and multiple selectable inputs, film capacitors on the driver board, and higher end parts like Nichicon Gold Tune power caps, Cardas binding posts, and Cardas RCA connectors.

Cardas wire, RCA connectors and binding posts



Other nice additions to the build include a 6 position Grayhill selector switch and the Alps Blue Velvet RK27 (100K) volume potentiometer, both with the corresponding ChipAmp BrianGT PCBs. The RK27 board is handy as you don't have to discern which pin is which (the white screen tells you which wire goes where). It's also a little easier that soldering to the little pins. The Grayhill switch's pins are so minuscule that you really have to use the board, it's not like an Elma or Goldpoint with larger gold solder lugs. The nice thing is the combo is a fraction of the price of the fancier selector switches.
  

Chipamp's PCBs for pre-amps / integrated amps


This project would require a larger box than the Bud 7" x 12" x 3" aluminum box I used previously. Rather than build my own gravity mount chassis, I wanted something a little different this time. I turned to Horace Atkinson of www.iagaudio.com for a robust 17.5" W x 10"D x 3.75"H chassis. I stumbled upon his chassis work on eBay: it's a nice combination of aluminum and wood panels for sides, as well as attractive wood accents on the bottom. The metal used in these chassis is a thicker gauge, one piece .125" aluminum tubing, so it can support heavy transformers without any bend or flex. (FYI IAG offers thicknesses up to .188"). The bottom features perforated sheet metal for adequate air ventilation reaching the heatsinks cooling the LM3886. A unique feature is the wood side panels actually act as feet, holding the aluminum portion up higher to allow for ventilation, very cool!


IAG Audio aluminum and wood chassis 

A view of the bottom with the perforated sheet metal removed. Note the bottom of the chassis is not completely open due to the rigid, tubular design, however underneath the wood side panels, there are removable metal panels that can be removed by unscrewing two flush mounted screws to give you adequate access for drilling, etc.

Chassis interior

As noted, the wood panels are all easily removable if you decide you want to access the sides of the chassis interior or change the wood stain, etc. Horace found some beautiful figured maple for me, as you can see below:

Figured maple side panels and accents
After much internal debate, I decided the chassis would be colored to match some of my other equipment with a red and cream color combo, so the wood was stripped down and stained a deep red hue, then given a number of generous coats of MinWax Satin Clear Urethane.  

Red stain and urethane on Maple

Now that the wood is my a nice shiny red, it's time to drill the chassis. After planning out the layout in Photoshop, the chassis is prepped with a ruler and sharpie and taken to the drill press. Many of the holes will be countersunk for this project. The others will be deburred using a Skaviv deburring tool with Cobalt bits. The IEC hole is trimmed using the typical combo of drilling four holes in the corners and using a Dremel cutting wheel to remove the rest. 

Chassis prep

For the heatsinks, I found some reasonably priced ones on eBay that had mounting holes for screws. The instruction manual from Chipamp says you can also use a 3"x3"x1/2" piece of aluminum in free air in certain applications. I installed 1" aluminum standoffs on the heatsinks so I could mount them to the chassis. Small drilled venting holes will be above them so when heat rises it can escape the chassis. 

Below is the chassis after a nice cream colored powdercoat. 



Since the amp is dual mono, it gets not one, but two chunky toroids. The transformers are always what weigh down an amp (big magnets with large quantities of copper wire spun around them aren't the lightest of materials). The pair, with steel cases, weigh in at a healthy 22 pounds. These are 300VA rated units from Antek.



Below is one of the toroids in a steel case. I had these powdercoated brick red as it makes a nice accent color for the cream. Typically the steel cases are used as a shield within a chassis, however I'm using them as both a shield and external transformer covers. I don't think I've ever seen a solid state amp with external transformers (usually they're just hulking boxes) so this will be a unique design choice.  




I'm adding the Power Supply Soft Start Board (or SSB for short) from DIYAudio for this build, this allows a gentle inflow of power on startup, which protects the power caps and should offer a more reliable service life for the amp. 



With everything ready, the chassis can start to get filled in. Shiny Cardas RCAs adorn the back of the unit, the binding posts would have been a bit tight on the back, so they were mounted to the top of the chassis right behind the transformers. Four large film caps will be residing in this chassis as well, so you'll notice some zip ties within the chassis as well.




Getting everything in place was a tricky predicament, as the sides of the chassis which held the heatsinks were screwed in place, then the wood panels were screwed to them, but the capacitors would have to be slid in to be held and secured, so order of operations took precedent. 

The power capacitors were a bit tall, so I had to use some minuscule PCB standoffs so they wouldn't come in contact with the chassis. The film caps, as you can see, were a perfect fit. I made a few small turret boards to keep the wiring neat. Cardas wiring handles all the signal work and thicker power wires as well. If you look carefully you'll notice one of the blue wires exists after the potentiometer to the RCAs to handle subwoofer duty. 



And the final product, see what you think:








Final weight was about 40 lbs. thanks to the hefty transformers and very solid tubular chassis. It's a unique take on a solid state amp, not the typical big black box with heatsinks on the side, but a more vintage tube-amp looking chassis. The sound is excellent, will be looking forward to putting it through the burn-in process and most more impressions.


The Fine Print:
Please remember that building/modifying circuits can be dangerous to you and/or your surroundings and should only be performed by a certified technician. The owner of this blog and all associated parties can not / will not be held responsible if you attempt a build or modification posted above and cause physical harm to yourself or your surroundings. Many electronics contain high voltages that can kill, and mods, if performed improperly, can be a fire hazard. Please keep this in mind.