GZ Vinyl "Quality Control" (or lack of) see pics!!

If they were sent plates from a lacquer that was not de-horned then GZ is indeed not at fault. The horns are created when the lacquer is cut. Usually a vacuum system removes these from the lacquer before the negative-plates are made. GZ is stuck with crappy product if the lacquers or plates are bad.

 

That is correct.We were also given the option of NOT having the plates cleaned (which was cheaper) but chose to go with the clean (more expensive) process. The difference in price is fairly small. The result is prefect and clean vinyl. I assume anyone who gets dirty looing vinyl back skimped on that cost.

 

I've seen that kind of 'texture' or marking on U.S. vinyl going back decades .. to the 1970s. Never saw it on U.K. or European vinyl though. Mind you, it never affected playback in an adverse way but it looks a bit funny. I never knew what caused this until I read this thread.

 

Ah, there you go. Everyone at the pressing plant is drunk!

 

I only have two LPs pressed by GZ. One is a 2012 re-release of a wonderful Czech 70s prog group Flamengo. It is a quiet pressing and came in pretty nice condition, however the 'remaster' is tantamount to cultural barbarism, but that is probably not their fault.

The other one is a 2009 release of Magma MDK I got this week. This one has the same extensive 'horns' shown above, and also came HORRIBLY dirty, with fingerprints, dust, etc. After cleaning it plays mostly quiet also, except it has a nasty scuff that causes repetitive clicks for about 15 seconds. Again, the mastering is diabolical, probably not their fault either, but as it sounds awful in a similar way to the Flamengo record, it makes me wonder...

The records were in medium weight stock paper die-cut dust sleeves. Not great.

 

I would guess that the horrible sound is simply due to a substandard master and then a quiet cut, which seems to be GZ's default way of cutting, unless they are told to cut loud. Their actual cuts are very good just a little on the quiet side, as if they are used to cutting for classical records. Again, the "horns" will probably be from an uncleaned plate, although why these are not cleaned a standard is odd, especially since it pisses people off so much.

 

I meant 'quiet' as in 'not crackly', not quiet as in 'low volume'. The records are not particularly low volume. They are both, however, devoid of any dynamic range whatsoever.

By the way, GZ is the privatized incarnation of the old communist era Gramofonove Zavody (Gramophone Works) pressing plant. The old plant was extremely well regarded, especially for classical music pressings. They also pressed some rock titles and turntable setup records in cooperation with the Czech Hi-Fi Club - a 70s group of Czech guerrilla audiophiles which found ways to work around the state bureaucracy to develop and sell decent quality affordable audiophile equipment made entirely from domestic parts, which was quite a feat in those days. On the record pressing side, they essentially hounded and badgered the pressing plant into cutting and pressing the records in question to the highest standard possible.

 

They should NOT give the customers the option to order vinyl without cleaning the plate. This way they (GZ) will always get the blame....

 

Cutting
We are able to analyze signals before going into the cutting head and the sometimes used lower cutting levels (compared to some other cutting studios) are the best loudness/quality compromise for those audio signals and result in much less distortion compared to the loud levels. There are limitations regarding geometry of grooves and cutting styli. If you are close to these limits then the distortion starts to raise rapidly. Unfortunately some audiophiles (I hope only minority of them) then try to explain resulting ultrasonic peaks in audio spectrograms (like signals above 20 kHz) as an advantage of a vinyl medium to digital sources, CD-Audio etc. But the same ultrasonic distorted peaks can be obtained also from using high cutting levels on audio cut from analogue tapes so those discussions are only a waste of time. Back to your note: we try to cut the way not overloading our DMM cutting heads and all the cutting system components and for the records to be playable on well calibrated turntables with at least average cartridges and clean elliptical tips (we use Ortofon OMB 5e for testing which in not an expensive piece of equipment). Our standard way of cutting is probably not enough loud for most dance/electronic genres, but then there is a loud option or a possibility to specify customer's wishes in a detailed way in documents sent with his order. Then they should be aware of vinyl distortions added to their audio files even if they are not able to hear them in most cases (as most non-audiophile people cannot hear MP3 artifacts and changes). We have two DJs here as premastering and cutting engineers and 8 more people with rock/jazz/beat and other direct musical experience, some of them former professional musicians. 18 specialists and engineers work here in vinyl part of our premastering/cutting department and we cut 50-70 plates per day. These two DJ guys prepare and cut dance titles the way our customers are satisfied with and they want them namely to process all their titles. I must say that from an audiophile point of view there must be distortions, there are changes to sound of their source audio (limiters, filters, compression), but these customers like the results and they have loud records. The same approach cannot be used for most pop/rock/jazz/metal titles where we prefer already pre-mastered vinyl-compatible sources. Nobody here wants to spend days of discussing claims with customer's mastering engineer that we changed his/her perfectly mastered audio files.

Horns
There are companies which DON'T WANT TO DEHORN (POLISH) mothers created by us from lacquer foils supplied from external cutting studios. Probably due to some notes read somewhere that an incorrectly done dehorning and polishing can lead to loss of high frequencies. This may be true, but I didn't notice any difference when doing a listening test of test pressings produced from both the dehorned and the not dehorned mothers. Who knows the truth... Well we tried to dehorn some mothers as a standard for one customer without noticing this to him (because most processing steps are not known to many of customers), but the aggressive reaction of our customer, when he later discovered that, stopped any effort to implement this step to lacquer part of our production. The customer is responsible for using external cutting studios and supplied lacquers and therefore test pressings should be ordered and accepted/rejected. Unfortunately some of them are in hurry and want to skip test pressings. Surprisingly we have more feedback from this forum (and similar ones) than from some customers directly. Strange. Finally, I am not a pressing expert nor an expert for electroplating, I can only forward complaints and reviews of our products to other people working here.

My posts also should not be considered as official statements of GZ, they are only my personal opinions .

 

Hi-it is actually good to hear from you and thanksfor the insight. I had 2 LPs cut at GZ via DMS and the first cut was superb due to the master. I will read your comments carefully and for the next project I will contact you with some more questions, best Markus SUGARBUSH RECORDS

 

Jiri, two questions:

1 Why would a customer respond in an aggressive manner when you do something EXTRA?
2 Why do you stop doing this after ONE negative response?


Cheers Robert

 

Question for Jiri. Why on earth would a label go to the trouble of having lacquers cut by a specialist mastering facility (probably from analogue source) and then skip on doing a test pressing? I assume that GZ would test play pressings anyway to make sure all is well before manufacturing a potentially faulty run?

Also is there an easy way to tell from the deadwax which GZ product is in house DMM from digital files or manufactured from outside lacquers which may or not be analogue sourced?

Thanks. Paul.

 

Sorry, it wasn't clearly said by me.

1. Because there is a controversy in the pressing industry about polishing/dehorning mothers. We didn't ask that one customer for his confirmation of the polishing, we hadn't known it was so big problem for him and he was very sensitive to this. These customers were afraid about the sound of their records after polishing (probably had a bad experience with another pressing plant), but the sound can be spoiled by many other factors during production of records - many production steps, many people and old machinery involved...

2.We DO POLISH (dehorn) mothers for some customers, they have no problem with it, but it is forbidden to do it as a standard for several others (some bigger ones as well). Of course it is better to receive lacquer foils without need of any polishing, I mean perfectly cut foils, which would reduce this additional delicate polishing step and make electroplating easier. There should be more press to lacquer cutting guys to check carefully their foils in a microscope after cutting + not cutting very deep grooves, extreme high cutting levels, check heating of their cutting stylus etc.

 

Short answer to Q1: I don't know, probably they are in hurry due to their release day being very close...
Short answer to Q2: QC is done for one TP and then for a sample of one pressing batch, but we want to improve our QC this+next year even more (more equipment, a dedicated software, more people...). No human and no machine is perfect :-(

Answer to Q3 (copy and paste of my old posts):

Our matrix numbers (must be machine ones) have been present on all records pressed by GZ Vinyl since 20th century, even if the customer supplies us with his own stampers (very rare case).
The actual matrix indexing since 2003/4: increasing number per title e.g. 109191 now + suffix E,M,H,O,F or N (size and revolutions code) + number 1,2,3 etc. (side index 1 = A side, 2 = B side) + "/" + additional processing suffixes.
E.g.: 109191E1/B means 33rpm LP, side A, 2nd cut/plate
More info here: http://www.discogs.com/label/GZ+Digital+Media

Moreover, if we cut a copper / lacquer plate here we don't add any handwritten info. A record with handwritten info wasn't cut by GZ for sure, but if you also can find our matrix number there, it means that the lacquer/copper plates or mothers were supplied to us by a customer and then we galvanized them and pressed the records.

1) our matrix number + any additional handwritten info = pressed at GZ, but mastered & cut elsewhere
2) our matrix number & no handwritten info = pressed at GZ, but you cannot be sure where it was cut until confirmed from other sources (a broker, a label, a band, a cutting engineer etc.)

It is not possible to identify analogue/digital sources from matrix info. In my opinion A/D is not a relevant question. Esp. for us, engineers knowing the scientific background for audio recording technologies.
Does the record play good or not should you ask? Read all the reviews (here, amazon, discogs, friends...) and then decide. Or just try your luck.

 

I agree. There is no excuse for that.

 

Just discovered the vinyl version of my own album (coming out this summer) is being pressed by GZ. However, we got test pressings and they are clean and great. I'm inclined to think that any issues with these are not with GZ per se but with what the label requests; it's not GZ's fault things don't have polyliners, that's the label's fault for not asking for them (or for test pressings). Our test pressings were clean and flawless.

 

...as were mine. I've yet to find a single flaw in the entire run, a claim I don't think could be made by any US plant.

 

Sweet f**K! Playing frisbee in the companies car park with vinyl hot of the presses before packing it should be banned there. Was Neil Young foreseeing those abominations when he sang "I've seen the needle and the damage done"?

 

My Rolling Stones 1964 - 1969 box pressed by GZ is among the best pressings I purchased in the last few years. I've had substandard LP's from a number of other labels in that same time. I wouldn't be in a hurry to single out one pressing plant.

 

I'd like to know if the problem pressings were lacquer cuts. My own experience is that 'horns' are created in mastering, and are undesirable because they cause problems with the metal parts (matrix) stage - sometimes making the mother and stamper hard to separate, or in extreme cases, 'tearing'. Lacquers have to be 'silvered' with silver nitrate so they can be electroplated and this stage is the cause of a lot of clicks, pops, and noise.
DMM mastering bypasses all this as stampers can be taken direct from the cut, which is not only better quality but more cost effective. There were two things that disturbed me slightly from the GZ video, firstly the vinyl hopper near an open doorway, and secondly the manual LP press requiring touching the still warm and partially unset pressing. Our Toshiba-EMI automatic presses inserted the disc straight into a plastic sleeve.
Finally, any debris from paper sleeves should brush off. If noises remain, it's a matrix (plating) problem or vinyl impurities.

 

Your post is interesting as is this entire thread as it evolves. I have only 2 GZ pressings and I have noted in each instance that the disc surface is not in pristine/new condition. On closer examination, I can see numerous scuffs or small scratches or damage on the surface, suggesting to me that these records are not handled carefully once they are pressed. I presume that they do not come off the presses like that? I buy secondhand/used records in far better condition, visually.

The records in question, Los Lobos 'Tin Can Trust' (not too bad) and Sandy Denny 'Sandy Denny' play with random pops which I attribute to the surface damage. The Sandy Denny is much worse than the Los Lobos as the clicks and pops are quite prominent and one or two definitely sound like bad scratches. I have no use for this record, which is also warped. It is a replacement copy for an earlier one, also bad.

As far as I am concerned, GZ Vinyl is now on my boycott list of plants that are a waste of time and a waste of my money. I hate paying my hard earned money for bad records. I think 'slapdash' sounds about right to me on the basis of my experience.

I was talking with the operator of a UK Indie label recently who told me that he uses Optimal as his first choice but sometimes uses GZ although he indicated that he didn't rate their pressings and only used them when he had no other choice. This, by the way, was without any comment from me, on GZ vinyl. I merely wanted to know who pressed a particular record that I wanted to buy and he confirmed that it was Optimal. He offered this opinion[on GZ Vinyl pressings] of his own volition. On that basis, the shortcomings of the GZ Vinyl pressing operation is known in the industry. I can't understand why a major label like Universal is giving them work unless of course it is due to lack of a better option at certain intervals.

 

A while Amazon Canada offered the 5 LP Grrrr! box set by the Rolling Stones [on the Universal Music label] on sale for half the price it normally sells for. Upon delivery I discovered it was pressed at GZ in the Czech Republic. All of the sides of all five LPs had scratches and marks on them. Obviously just sloppy, careless handling at the factory - apparently, no quality control, what-so-ever is evident. I returned the set for a replacement and just received another copy. Only opened the first LP yesterday; it too is in the same poor shape. Although, the marks and scratches don't seem to affect the sound as I played it. Won't buy anything pressed at GZ again. Debating whether I should return this set, too; although I know another replacement will be in the same poor shape.

 

I'm in much the same position as you. Frankly, I am embarrassed at the prospect of having to send the 'Sandy Denny' LP back again. I feel sorry for retailers who have to deal with stuff like this too. But on the other hand, if I do nothing about it, Universal (and other labels) will keep using this plant. There is a 'small' possibility that if people complain something will happen for the good.

 

Yes, horns are created when cutting a lacquer with an over-heated stylus, cutting too loud, cutting too deep and usually a combination of all three. Horns are not sucked away by a vacuum. If it was that easy every plant in the world would be doing it.The vacuum on the cutting lathe is to suck way the lacquer that has been etched to make the groove. Its like a long piece of cotton.

The answer from GZ is correct. A record with plenty of horns will rub against the paper bag and leave these marks. If that same record was in a poly sleeve you would not see these marks. Even so, there is no excuse for grit or dirt to be covering the record.

De-horning mothers is a lost art. It is time consuming , too. Note that the horns contain modulation (signal) and polishing them away also takes away some of the signal. To give you an idea of what a horn is, imagine cutting a record in half and looking at it sideways. The "horn" can run along the entire length of the groove or just in some parts. It looks like a wave extending up the groove walls and overflowing. The trick is to cut a lacquer correctly and minimise horns or to de-horn the mother which is only possible when using the three-step plating process (ie. master/mother/stamper). If using the one-step plating process (ie. using the master as a stamper) then there is no opportunity to de-horn the mother because there is no mother.

Another thing to consider is the usefulness of cutting a lacquer and sending it to an overseas plant. The freshly cut lacquer disc should be silvered and plated right away rather than packed and shipped to a plant that might be days away. Exposing the cut lacquer disc to heat in transit is not good as the lacquer is soft and the grooves can deform. Just watch the wax on a candle deform after you light it.

Apollo, makers of lacquer master discs, recording a SHIPPING TEMPERATURE range of :
70 degrees, +/-10 degrees F (21 Degrees +/ - 5.5 degrees C). .

This is obviously not going to happen in summer when the cut lacquer discs are in transit.

It's easy to criticise a plant or believe the myths you find on the 'net by uninformed people. For example, the myth that "thicker records have deeper grooves".... Again, from Apollo, the lacquer coating on the master disc has a thickness of 0.178mm +/- 0.0127mm. Therefore you can not cut a groove deeper than this so it doesn't matter if a 12" disc weighs 140g or 200g. The groove depth is the same. And by the way, anything more than 140g is a waste of vinyl.

Obvious observations and criticisms regarding dirty and scuffed records are fine but pretending to understand the entire manufacturing process and criticise something you don't fully understand is not so fine. If you don't understand.... ask.



L

 

That's quite a second-ever post. Very informative, if a bit confrontational at the end.

I have a lot of good sounding vinyl pressed from stampers that were not de-horned. I never thought the sound on these pressings was inferior. Especially if you use a microline stylus for playback, as I often do, the stylus is nowhere near the affected, upper wall of the groove.