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Product Review - Crystal Vision VPS-1 Video Processor - January, 1998

By Stacey L. Spears


Crystal Vision VPS-1 Front Crystal Vision VPS-1

Video Processor

Inputs: Two Composite Video, Two S-Video (Pass Through)

Outputs: 1 S-Video

Size: 2.3" H x 8.5" W x 6" D

Weight: 2 pounds

Price: $549 USA



Camelot Technology Inc., 30 Snowflake Road, Huntingdon Valley, Pennsylvania 19006, Telephone: 215-357-8356; Fax: 215-357-7859; Web E-Mail

Le Intro

I received an e-mail from Howard Schilling at Camelot Technologies, saying that he would be shipping me the new Crystal Vision VPS-1 Comb Filter by Friday (12/19 a.k.a. the opening of "Titanic"). I figured it would not arrive until after Christmas, but come Monday (12/22), to my surprise, a box from Camelot was waiting for me. Looks like Santa came early!

The Crystal Vision VPS-1 (VPS-1 from here on out) is a comb filter in a box, like the Faroudja and Audio Alchemy units reviewed here in Secrets previously. The VPS-1 was actually designed by the same folks that built the original VRE (Peter Madnick and Neil Woodall), but the VPS-1 is not an enhanced VRE. Rather, it is an entirely new product designed from the ground up.  The VPS-1 has the name "Crystal Vision" on the box, but Camelot Technology is the exclusive worldwide distributor for it.

For the last eight months, since the release of DVD, my LD player has gotten very little use. It's hard to go back and look at LD. It is still one of the best consumer video formats available, and I know there are some LD enthusiasts that hate DVD because it's pure digital. But the fact remains that DVD is a superior format. It stores the video in the component domain and also supports 16x9 enhanced resolution. There are a few, and I mean few, 16x9 enhanced LDs, so LD could be better, but there are not enough widescreen TVs to support such a move for the software industry.

So, with the release of DVD and DSS, why would anyone want a comb filter in a box? I can personally name 300 reasons: my LD collection. I am sure there are others out there who have even larger numbers of discs in their home theater libraries. Then there is VHS, C/KU band satellite dishes, and even cable (routed through your VCR).

My first look

Being the eager beaver, I ripped open the box and plugged everything in, without reading the instructions :-(  I used input 1 for my LD player. Then I stuck in a copy of Video Essentials (VE) and immediately started with some test patterns. At first I was a little disappointed, as I saw some artifacts when using the edge enhancement. So after observing this, I grabbed the instructions and proceeded to the bathroom (I get all of my important reading done there). Much to my excitement, I found that there are 4 settings for the edge enhancement. Input 1, which they recommend for your VCR, has the edge enhancement set at 3.  Input 2, recommended for LD, has the edge enhancement set at 1. I made the adjustment on the VPS-1 and the problems went away. These guys did their homework! So, make sure you read those instructions before you begin.

The aesthetically pleasing little box

The VPS-1 is like no other, and it is a fine piece of workmanship. The box is silver, not the normal black like every other box in your A/V system. The faceplate is concave with a slight indent where the green LEDs are located. There are two LEDs on the left, labeled Comb" and "Edge". On the right are 4 LEDs labeled S1, S2, C2, and C1. On each side of the indent are two buttons with no labels. The left button affects the edge and comb, while the right selects the input sources. I will say more on this later. Crystal Vision VPS-1 Face


Crystal Vision VPS-1 Back The back of the unit is straightforward. It has one power, three S-Video, and two composite video connectors. One of the three S-Video connectors is for the video output, while the other two are for the S1 and S2 inputs. The two composite connectors are the C1 and C2 inputs.

The power supply is the type that I like. It has the box in the middle with a two-prong plug on one end. This power supply takes up only one socket on the outlet unlike the ubiquitous wall wart that hogs the entire outlet.

Beauty is not just skin deep

The VPS-1 uses the Phillips 8763 10-bit A-to-D converter on the incoming composite video signal. The signal is then fed to their (Crystal Vision) custom digital signal processor. Both the comb filtering and edge enhancement are done in the digital domain, and then the signal is run through an Analog Devices ADV 7128 10-bit D-to-A converter. The S-Video switching and output buffering are implemented with Linear Tech 1260s 130 MHz video op amps (operational amplifiers - see glossary).

The algorithms for the comb filter are all developed in-house and can be updated with a change of an EPROM. Since they (Crystal Vision Engineers) were the designers of the VRE, they have spent much time refining the technology, and the results show. The edge enhancement in this unit is their proprietary design, and the circuitry creates a "harmonic" of the original signal, which causes the high frequency sine waves to look like square waves. The different levels represent the amount of gain applied to the harmonics.

Operating this new piece of equipment

The operation of the VPS-1 is similar to former Audio Alchemy products, and by using a combination of the buttons you can obtain different results. For example, when both the edge and comb LEDs are lit, you can hold down that button (the left one), and the LEDs on the right will illuminate. The number of LEDS that light up tell you what level of edge enhancement you are using. You can then press the right button to change the level. The input selection, by default, is set on auto, so as soon as a source comes on it stops there. If you want to turn this off, you can hold down the right button, and then press the left one once. Now you are free to use the right button to change the source. This may seem a little difficult at first, but as soon as you do it once, you will realize that it is a piece of cake.

Before you plug the VPS-1 into the wall, connect all of the sources and the TV, next plug the power supply into the VPS-1, THEN you can connect the power supply to the wall (old Audio Alchemy habits die hard).

Getting to the important stuff, i.e. performance

In a sentence, a new king has been crowned. No, not Arthur (another product from Camelot Technology). Since the VPS-1's roots can be traced back to the VRE (the same crew!), I will first describe the differences between the two. The original VRE review can be read by clicking HERE.   As I said before, the VRE is a completely different product, a stepping stone if you will.  The VPS-1 design started with a clean sheet of paper.

The VPS-1 has been improved in every way:

The VRE was great at eliminating the dot crawl, but it did soften the picture slightly. The VPS-1 has no such softening effect. In fact, when the edge enhancement is used on the VPS-1, the picture is actually sharper than without the VPS-1 in the signal path.

Cross color artifact  is one problem that never seems to go away.  Cross color is a rainbow like pattern that shows up on fine detail like the rim of sunglasses, or on chain-link fences, venetian blinds, etc.  This is where a 3-D comb filter looks good on static images. The VPS-1 still has this artifact, but it seems to have been reduced. When you look at the Snell & Wilcox Zone Plate pattern (S&W) on Video Essentials [Frame: 29939 to 30798] it is quite evident. This pattern is difficult for any video processor to handle, and it will cause any inherent problems to become manifest. When looking at movies, cross color is MUCH less noticeable with the VPS-1. Using the same test pattern, you can see the effects of too much edge enhancement when changing the level. As soon as you hit level 2 and above, you will notice some cross color start to appear in boxes around the screen.  The only product that I have seen that has been able to remove the cross color totally is the Faroudja line doubler and quadrupler ($9,995 and above).  They have a cross color suppressor that softens the diagonal lines, requiring their special detail circuits.  The Faroudja VP-100 comb filter does not suppress cross color.

Battle royal

How does the VPS-1 compare to the Faroudja VP-100? First off, their names are pretty close, so I will call them CV for Crystal Vision VPS-1 and Faroudja for the Faroudja VP-100.

To make things fair on just which is the better comb filter, I set Gain and Delay at 0 on the Faroudja and turned off the edge enhancement on the CV. I used a 1-meter run of Monster M1000-V composite video cable going from the CLD-97 to each box and a 4-meter run of M1000-SV going from the box to the TV. I used the same composite jack coming out my LD player for both units.

The CV exhibits less dot crawl than the Faroudja, and that is the bottom line observation. I used the running color bar test pattern on VE at the beginning of chapter 15. These bars are more saturated than the bars you normally use to calibrate your TV. The Faroudja clearly shows dot crawl between the yellow and cyan bars, while CV is almost perfect. These bars are more stressful on a comb filter and might not represent the material in the real world (watching movies), but they do show which is better when the pedal is to the metal. The same thing happens on the S&W pattern. There are three bars along the bottom that represent the chroma frequency response at 1.0, .5, and 1.5 MHz. Here the Faroudja has dot crawl evident on all three sets, while the VPS-1 has slightly wavy lines on the 1.5 MHz bars. chromafreqresp.jpg (5222 bytes)

So, each of the two products has its strengths and weaknesses. The Faroudja has the delay feature, which has proven to be very practical. On the other hand, the detail knob on the Faroudja isn't useful, to me, although it is an improved sharpness control that is better than the sharpness control found on any TV in the marketplace. But, as I said before in the review of the Faroudja, the default position is too high! I have mine set at 1 for LD. Anything higher adds ringing (edges next to edges). This can help VHS, but I rarely watch VHS anymore (I have finished watching my Highlander episodes). The Faroudja also has no switching capability at all, and from the number of questions we get on which video switcher to buy, this is a much needed feature. The Faroudja had a higher retail price, but they just recently lowered it by $300.

The CV has 4 video inputs, 2 S-Video and 2 Composite, with no noticeable signal loss when using them. The edge enhancement, unlike the detail on the Faroudja, does not appear to add any ringing. Of course, if you have it (CV) set improperly, you do get some cross color artifacts. I wish they would have added a delay function to the CV, but this would require a different setting for each source. They best way to do this would have been to put in 4 different delay pots or 1 pot that required you to change it for each source. Even DVD has delay when using the component connection, so adjustments for this should be added to future processors.  By delay I mean that the arrival of the Y channel and the C, or R-Y and B-Y, is not at the exact same time.   This causes a slight smearing at the edges of objects, and can be seen by looking [Click here to see pattern] on VE [Frame: 46625 and 46676], AVS [Frame: 50791, 50793, and 50794].


I have been waiting for this product ever since the 1997 WCES last year when Howard mentioned they had one coming. Following the arrival of the Crystal Vision VPS-1 in my home, I have been watching more and more LDs. Perhaps now I can get all of those DTS LDs reviewed and on-line! The VPS-1 is the best separate comb filter to date and makes a great video switcher to boot. Whether you own a 27" TV or one of those high dollar video projectors, the VPS-1 will improve your picture.  I hope to see more such innovative video products from Camelot in the future.

Stacey L. Spears


Manufacturer Replies:

On behalf of everyone at Camelot Technology and Crystal Vision, I would like to thank Stacey Spears for his wonderful, thorough review of the Crystal Vision VPS-1 2D Adaptive Digital Comb Filter.

This product is the result of tireless work by Peter Madnick and Neil Woodall, who have continuously reworked and refined this product over
many years into the masterpiece we have today. We believe the level of technology in the VPS-1 to be comparable with any video product in the
world, while also remaining eminently affordable. This goal of affordable digital audio and video excellence goes into every product we make, and we intend to build upon the standard set by the VPS-1 in the coming year with even more high-tech goodies.

As one of the preeminent magazines on the Internet, your coverage of our products means a great deal to us, and we support you 100% in your efforts.  As we have always believed, the Internet ranks as one of the most powerful informational mediums in the world, and as such we are devoting rapidly increasing amounts of attention and manpower in monitoring it. Our website ( will be updated in the next few weeks to be more informative and entertaining than ever, and we try very hard to respond to all of our e-mail inquiries within one week.

Once again, thank you so much for all of your time and consideration.


Howard Schilling
Camelot Technology, Inc.

Copyright 1998 Secrets of Home Theater & High Fidelity
Frame from Snell & Wilcox Copyright Snell & Wilcox
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