Stillpoints vs Blackpods

Stillpoint Ultra SS and BlackPods

In the audio land of exotic footers, Stillpoints reign supreme. The most common question I get about BlackPods is "How do they compare to Stillpoints". Well, until a week ago I'd never even seen a Stillpoint, let alone heard one. But this last week I've got my hands on some Ultra SS Stillpoints and I've been testing them extensively. Also I've had several audiophile friends come  over for a listen, and all say the same sort of things.

I realize of course that a comparative review written by the designer and maker of one of the products is likely to be viewed with suspicion (or worse). But I trust that my evaluation will be borne out by other's experiences in time.

This story starts with a visit to Audio Reference in Auckland - our local high-end shop. I'd gone to meet Terry and listen to a variety of footers. We used the system shown below:

This was a decent system, but was sufficiently different to make subtle comparisons difficult for me. We started out without any footers on the DAC. Then added the smallest Stillpoints, the Ultra Mini (us$375 for 3). That made an obvious difference. Then we tried BlackPods. Different again. Notably more bass. Then it was the turn of the Stillpoint Ultra SS (us$747 for 3). Better bass than the Minis. Lastly we listened to some Finite Elemente Cerapuc (around us$550 for 3). These had great bass, but notably less information coming through than the Stillpoints or Blackpods (currently $99 for 3, normal price $139 for 3).

Terry very kindly lent me a set of Stillpoint Ultra SS so I could do a proper evaluation. I did not think it worth borrowing the Ultra Minis, as they seemed to be some distance behind the Ultra SS in performance. At this stage I didn't really have a handle on how they sounded, as the system was unfamiliar and lower resolution than my normal system.

Test Setup

After some initial playing around and casual listening, I set about finding the best place for the Ultra SS footers. I used my DAC/Preamp as the mule, as this is most sensitive to footer changes. It's a Twisted Pear Buffalo III board, using the ESS9018 Sabre chip, running into a Broskie Unbalancer tube back-end.

I found with BlackPods that placement is important. You can alter the effect of footers somewhat by moving them around. So I wanted to find a good location for the Stillpoints. Turns out that they like the same sort of place that the Blackpods like, so that made testing easier. Also I found they sounded best with the 'hard hat' side up, slightly unscrewed (as recommended).

The rest of the test system, for those interested : Speakers Magnepan 3.6, Amp Goldmund clone that I breathed on a little, Front end, Squeezebox touch with Remedy Recloker.

Some of the CDs used: Patricia Barber: Modern Cool, Cafe Blue. Dave Matthews: Some Devil. Fat Freddy's Drop : Based on a true story. Keb Mo: Slowdown. Little Axe : Hard Grind.

Listening

I have to say that I was expecting Stillpoints to be better than my BlackPods. And on initial listening they sounded very impressive, making it easy to pick out detail that you hadn't heard before. They were clearly a cut above your average cones, or even 'good' cones like Black Carbon Racing Cones.

The most immediately apparent thing was that the Stillpoints had more treble, and the BlackPods had more bass. 

As I went back and forth between the two footers, I started having this heretical thought :

Wow...Blackpods are better than Stillpoints.

The extra treble that the Stillpoints had, while exposing extra detail, also seemed too much. Some vocals that work fine on Blackpods became sibilant with the Ultra SS (eg Too Rich For My Blood, Cafe Blue). This gave the effect of a top-heavy presentation. This was also compounded by the bass, which was richer, deeper and more controlled on the BlackPods. You could hear the bass lines with the Stillpoints, but BlackPods let you feel them as well.

So once I'd broken that mental barrier, I started noticing all sort of other things:

• Soundstage depth. One thing I've noticed with all the very best systems that I've heard - they all have a fabulous way of presenting soundstage depth. (and even height). I put this down to the fact that depth cues are very low level, often buried in other music and distortion. Only systems with truly high resolution can present depth convincingly.
  
  I noticed on several tracks that BlackPods portray a much more 3D soundstage than Stillpoints. For instance, one Fat Freddy's Drop track has this sound effect that appears to leap out of one speaker, come towards you in an arc, then go back to the other speaker. Artificial, for sure, but a cool effect. The BlackPods make you move out of the way. On the Stillpoints there's hardly any depth, the sound appearing to simply move between the speakers, not leap out at you.
  
  With Stillpoints, a track like Gravedigger (Some Devil) has a strange effect on the lead vocal, appearing phasey. With BlackPods you can hear that it's set well back on the soundstage.
• Musicality : the BlackPods are just more musical. They sound  more like music. The Ultra SS are more electronic sounding.
• Toe-Tapability. This highly scientific test measures how easily you tap your toes to some toe-tapping music. Some call it PRAT. Anyway, time and time again I found it much easier to for my toes to tap with BlackPods.
• Dynamics : I noticed that music seemed to have more sense of ebb and flow with BlackPods. More 'surprise factor' - the effect you get when an instrument comes in loudly and unexpectedly.

After a couple of days of this, I got pretty tired of the Stillpoints sound. My ears/brain dialled into their signature sound, so it became very easy to hear. Normally when I borrow gear I listen as much as I can, but with Stillpoints I only now use them when I want to do a test, or demonstration. I just don't find them as musical, as as enjoyable to listen to as BlackPods.

Conclusion

Given that BlackPods cost a small fraction of Stillpoints, they are a complete bargain. They are still $99 (for a set of 3) for the next few days. After that they will be $139 - and you can return in 30 days for a refund. But I can't seen anyone returning these..

I have to admit that I am quite surprised the way it's turned out. I really thought they would be better than this..

Christmas Shipping

According to New Zealand Post: 

If you want your parcel delivered before Christmas, kindly conclude your purchase a few days before the following dates:

International sending cut off dates:

                                       Australia              South Pacific, Asia,                  Rest of the world
                                                        North America, UK & Europe

International Air            10 December                       5 December                 3 December

International 
Courier                       15 December                       12 December                10 December

International 
Express 
Courier                       17 December                       15 December                12 December

SonarQuest Rhodium/Carbon Power and IEC plugs

I've been trying various power and IEC plugs when I get the chance. Sometimes customers request a particular set of plugs, for example Oyaide or Furutech, to be put onto their power cords.

Our 'normal' plugs are Chinese "OEM" plugs, which are very good value for the performance. However I was expecting great things from some of the more expensive plugs, ones costing $150 each or more. 

But although there was a difference, I did not think it to be a very large difference. Also it was hard to say which one I preferred. Some of this was due to an 'oranges to apples' comparison, for instance, out normal plugs are copper or brass. And I was testing against plugs made from bronze with exotic coatings (beryllium, etc..). And often I prefer the more musical sound of plain copper over plated conductors.

However, just recently a customer ordered a power cord with a SonarQuest Rhodium/Carbon plug set (actually a European Schuko and IEC). This very fancy looking combo is very nicely made with a solid metal body and Rhodium plated conductors. I don't know if the carbon helps the sound or is just for show. But they look very cool.

And to my surprise, these things sound very good - sit up and pay attention good. About the first time I've heard our standard plugs be humiliated like this. I was impressed enough to order some for myself. And I've added it as an option on our NEO and NEO-OCC power cords - it costs an extra $160 for SonarQuest Carbon Rhodium power plug and IEC plug. Highly recommended if you want to push the envelope.

Coming Soon - Mad Scientist Audio Footers

I've been developing some footers to place under equipment, and the performance is such now that I think they are ready to release.

Please note - these are just prototypes and are rougher than the production version.

How they came about is interesting.. An acquaintance, Richard, who runs Krebs Upgrades, has a bad case of the audio disease. He has access to CNC machines and he makes some rather odd-looking but amazing-sounding footers - they consist of a square block of duralumin, about 2"x2"x1", with the top half of a steel ball protruding from the top. There's a bunch of clever stuff going on inside the block.

I heard them first at my house when he and some others came over to "play stereos". I was gobsmacked. I'd not heard footers make this sort of difference before. Especially ones that look like a washing machine part ;)

Richard had been working on these for years, but didn't seem have any (immediate) plans to turn them into a product. They would have been pretty expensive - he said they cost about us$500 each to make, a lot of which is the CNC time.

This encounter got my mind racing, and I set about experimenting with footers. After making several dozen, I got the chance to try them again versus Richard's footers.

That was a bust. It took all of 3 seconds to hear that they were not in the same class. Richard said "They sound phasey, all over the place, they will give you a headache". I had to agree.

Back to the drawing board...

This time I think I figured some important things out about how these magic footers were working. Of course, any discussion of footers in the audio world will usually involve mentioning the industry leader, Still Points. These expensive and beautifully made footers are very good and very expensive. Or so I've been told. Richard said that he'd been lent some StillPoint Ultras a few months back, and he told me that he prefers his own footers. They work on a different principle, but seem to have the same basic aims. But a set of 3 Stillpoint Ultra 5 footers costs more than us$2000!

So after a complete redesign I got the breakthrough - I was late-night testing as usual, and tried the new design, followed by lots of shouting, waving my hands in the air, etc. I knew I'd found something. Some more development to refine and it was time to put them up against the reference - Richard's babies.

I got the chance to do this just recently. Usually this is a case of ritual humiliation, but this time was different. It wasn't so clear now which was best. Richard's probably, but it was close. I think there may have been some things that mine did better, and things that his did better. I'd need a longer listen on my system to both types to tell which I really preferred. Richard even used the words "sounds good", which is high praise.

Later on, I discovered that we hadn't even listened to the best sounding prototype - I'd only made that one a few hours before, and it was not fully set yet.

Currently I'm working towards the final product, which should look very similar to the picture above. They are 50mm diameter, 40mm high and weigh about 140g each. And yes, the ball is a lead fishing weight. Perfect for the job and cheap.

The best part is the price : starting at $99 for a set of three. Coming Soon (or email to harass me for pre-production units)

Update : here is a picture of the production units (and no, the ball is no longer a lead fishing weight).

Report on a "Goldmund Clone" amplifier from eBay

I recently bought a new power amplifier from a seller on eBay. It was sold as "HiEND power amplifier 195W*2 8ohm ,aluminum,base on Gold*Mund mimesis 29" The amp is rated at 195W into 8ohms, and uses 8 lateral MOSFETs per channel.

The Goldmund design is quite well-known among DIY amp builders. It was said to produce a very good sound quality. However, even the original Goldmund amps (some of them, at least) had a tendency to self-destruct. And the seller seemed to be warning about possible problems - here was his list of warnings:
1) do not only connect one speaker..
2) do not use tube pre-amp.
3) if you want change the signal or the speaker cable,you must turn off the power amp  first
4) when you  playing very very loud sound ,please  touch the heatsink and be sure the heat sink  no too hot so that can cook the egg..

So I went into this with my eyes open. One reason was price - about us$550 including shipping. I asked why no tube preamp, and got no answer. 

I was impressed when it arrived.

All-aluminium case. Large transformer. Speaker protection board. 16 lateral mosfets - these alone cost more than $10 each. It uses 2SK1058 and 2SJ162 MOSFETS. OK, not the original Hitatchi, but lateral mosfets are much better for amplifiers than the cheap switching MOSFETs often used.

And when I plugged it in to play, wow, it sounded great.

Problems..

For a few hours. It actually died while it was idling. Had been on for about 8 hours. One MOSFET blew and took the fuse with it. So I happened to have a few spares handy. 

I figured that the gate-stopper resistors were too small, so I replaced these with larger values - 470R and 820R (different values for the P and N channel MOSFETs, as they have different input capacitance). Gate stoppers are resistors that are meant to stop oscillation, which is a common problem with MOSFET output stages.

So that didn't work.

I spoke to the seller and he admitted that quite a few of the amps he sells have problems, but he claimed that this one had been running fine, in Hong Kong, for a week or more. I noted that HK has 220VAC. My voltage is 240V, so significantly higher. I wondered if this might be the problem.

I decided to try reducing the voltage that the amplifier saw. I used a trick that John Broskie taught me, using a 25 Volt transformer to subtract 25 volts from the 240VAC that the primary sees; this reduced the input voltage to 215VAC, which meant that the rail voltage dropped from 68-0-68 to 58-0-58

This solved the problem. The amp ran just fine now, and still sounded great. I also obtained a circuit diagram of the variant used in this amp. Thinking about what had happened, I figured that the problem was due to the voltage stage getting too warm, which caused it to oscillate at some point, which then caused a MOSFET to die, as the rail voltage was quite close to the MOSFET's max voltage of 140V. 

I tested this theory by making a simple regulator (using 56V zener as shunt) to power the voltage stage. The output and driver stages were still on 68-0-68. This also did not self-destruct, so it seems my theory was correct.

I plan to make a more sophisticated regulator soon, probably some kind of capacitor multiplier.

More Problems...

However, there was another problem with the amp. It uses 4 pairs of parallel MOSFETs per channel. And these are directly connected to the output. Most circuits use a low valued source resistor. This is designed to prevent one pair of mosfets taking all of the load current, using local feedback (degeneration). When Goldmund builds their amps, they match the MOSFETs so that this resistor is not needed. However this amp did not have matched MOSFETs I was sure. I did a high power test and sure enough, I managed to kill the amp again.

So I put in 0.1ohm source resistors. This made it much harder to blow the amp, but I still managed in the end.  Replacing them with 0.2ohm resistors solved the problem.

There you have it - a couple of small fixes and you have a great amp. I was amazed at how good this sounded. Compared to my main amp, the Moskido, a hybrid, non-feedback amp, I find the Clone amp to have more detail, speed, dynamics. But the Moskido sounds more musical. That's the magic of tubes..

And it works now just fine with a tube preamp! 

You Want One?

I'd be happy to explain how to make the changes needed to make this a functioning amplifier. I can also let you have the circuit diagram. I could even do the work for you myself but this would cost in shipping. But still a bargain considering that you'd need to spend a lot more than this to get an equivalent-sounding amp.

Black Discus on the Amplifier

As you can see, I've added a fair number of CanOpeners to the amp. I was trying them on the capacitors. The best place for them is over the heatsinks that cover the voltage amplifier transistors.

More About Power Cords

I wanted to cover a variety of Power Cord related things in this post.

UP-OCC Copper Wire

Teflon and Cold Creep
Firstly I want to say a few things about safety and our power cords. Questions were raised on a forum, although the person doing the questioning was a rival manufacturer with more expensive cords to sell, who knew nothing about how our cords are constructed.

Anyway, the point raised was 'cold creep', a problem that Teflon can have. This is a phenomenon where a plastic (or other material) deforms under the influence of stress over time. It's not a mystery and the rate and extent of creep can be (and has been ) analyzed and graphed.

I was aware of the potential for problems when using Teflon insulation for power cords, but took steps to prevent this from being an issue, and also set about testing the robustness of the solution. There's a few places where creep can occur - along the length of the wire of course, if say a heavy amplifier were sitting on the cord, but also by the cable stress-relief glands on the power and IEC plugs.

Along the length of the cable, the conductors are each covered in a cotton sleeve - this resembles a thick sports-shoe shoelace. And where the stress relief occurs on the plugs there is an additional thicker layer of cotton and also heatshrink.

A number of tests were performed on the wire, both the inside cores (with one layer of cotton) and the finished cords. In one test, the two twisted L and N conductors, with only the one layer of cotton, were gripped by a large Mole Grip such that the wires were being deformed as the distance between the jaws of the grip was about half the diameter of the wire. The mole grip was left on the wire for an extended period (weeks).

This test quite easily shows problems on plain teflon wire, but with the cotton sleeve there was barely any damage and certainly no loss of insulation integrity. 

In real life, the cords have an additional, (thicker) cotton sleeve over the top, making it even harder to damage. Of course we don't recommend that you treat your power cords like this.

Why Teflon?
Others asked "Why use Teflon on power cords? The arguments about dielectric absorption don't apply as there's no signal going down the power cord"

The simple answer to this is "Because it sounds better" .. In fact it's the same reason for the white cotton sleeve, the black heatshrink over the filters.

NEO-OCC
I've been trying some UP-OCC wire in power cords. I managed to get some 11AWG OCC copper wire with Teflon insulation, and I've been listening to them for a week or more.

How to describe? More dynamic. Lower Noise Floor. But mostly more real sounding.

I did find that I had to add a couple of FIRST kegs to get the sound nicely balanced. So I have just put these on the main website and in the store so they are now available.

Power Cords

I've released two new Power Cords. Well, I call them power cords, but they are really BlackDiscus-based power filters with power cords attached. Their performance mostly comes from the filter. The power cord part on it's own sounds pretty good but not in the same ballpark.

NEO Power Cord

So why power cords? How on earth can they make any difference?

If you listen to the flat-earthers at diyaudio, they will tell you that the power has already gone through miles of very ordinary copper and what possible difference could the last meter make. 

But like many common sense observations, the truth is more subtle than that. It's best to look at the power delivery system of your whole audio set-up. Some lucky folks have separate lines for their audio system, and I'm sure that really helps. Then you don't have to worry too much about all the computers, air conditioners and so on.. But usually there's a range of audio gear powered from essentially one source. There's power amps, with their strange, music-modulated power grabs, taken in sudden bites 120 times a second. Then there's digital components with corresponding HF interference. But to think that it's all just current through wires is also a gross simplification - currents have associated magnetic and electric fields. Then there are the external fields that are all around, nowadays reaching well into the gigahertz range where it's real hard to get a handle on without huge amounts of money. 

These fields all interact in predictable, but complex ways. 

Looking at the way components draws current is instructive. Anything that uses DC for power will need a power supply that converts AC to DC. That means all audio gear. And these supplies inevitably contain rectifiers, which switch the current on and off, either 120 or 100 times a second (depending where you live).

Engineers call this "a horrible power factor". And no, it's not possible to fix up this kind of power factor problem with a few capacitors. In fact it's darned nigh impossible to get a power amp to present a benign load.

Picture a pipe with a high pressure water supply at one end. At the other you have a electrical valve that operates almost instantaneously. Consider what happens if you switch the valve on and off rapidly. It's not hard to imagine the back-pressure waves in the pipe, and those waves causing problems for other users of the same supply. In fact this problem occurs in real life with water supplies.

This is what is happening in your power amplifier's power cord. (well, not literally, but you get the idea).

So one of the purposes of the BlackDiscus filter is to help isolate the power amp from the other parts of the system. In other words, to filter the junk coming out of the amp onto the power supply system.

Then there's the more obvious function, which is to filter noise and interference from the mains supply. Note that some of the noise and interference might be coming from other components..

FIRST Power Cord.

There are two models of Power Cord - FIRST ($139) and NEO ($399). They differ in the type of filter. 

FIRST uses 3 Kegs. Two are special magnetic Kegs, on Live and Neutral, with a normal Keg on Earth.

NEO uses a "Power Purifier" style filter using 3 Blue Sticks, as well as a 3-Keg filter. This uses magnetic Kegs with Neodymium magnets inside. 

Note - don't think that the Neodymium magnets are somehow more 'high end' than the kegs used on the FIRST cord. They are simply the right ones for the job. Actually the kegs used on the FIRST are much more hassle to make and also cost more. If you swap kegs between the NEO and FIRST, the result is that the FIRST would have excessive sibilance, and the NEO a slightly recessed top end.

This is also the reason we are not doing versions with more kegs. This is the right number. If you put more on, you get worse sound, less balanced.

The FIRST Power Cord is a complete bargain. It won't stay at $139 for very long. It sounds much more similar to NEO than different. NEO is more refined and sounds more real and 3D, but if they were priced according to their performance, FIRST would cost $299  (if NEO is $399)

I think it's likely that these Power Cords will be classed as giant killers. I've never heard a Power Cord make anything remotely like the difference that these make. But the most expensive power cord I heard only cost a mere $1200. (But others tell me that the NEO beats cords costing much more than that)

More info here http://www.madscientist-audio.com/power-cords-and-filters/