Author Topic: ZVEX BOX OF METAL  (Read 18256 times)

jonathan perez

Re: ZVEX BOX OF METAL
« Reply #20 on: November 22, 2007, 01:37:27 AM »
Quote
I've heard that it has all surface mount components inside.

You still can have a good pedal with surface mount components, just check a NIG.

surface mount just means its harder for YOU (general) to work on/mod.
no longer the battle of midway...(i left that band)...

i hate signatures with gear lists/crap for sale....

i am a wah pervert...ask away...

12afael

Re: ZVEX BOX OF METAL
« Reply #21 on: November 22, 2007, 01:09:14 PM »
smd resistors have more noise than truhole Rs, you can find smd poliester caps but on cheap pedals all that you can find are ceramics.

WGTP

Re: ZVEX BOX OF METAL
« Reply #22 on: November 22, 2007, 01:18:05 PM »
OK how about a BOR with the booster in front of the distortion.   :icon_twisted:
Stomping Out Sparks & Flames

ambulancevoice

Re: ZVEX BOX OF METAL
« Reply #23 on: November 22, 2007, 03:54:14 PM »
hmm
i was thinking clipping diodes somewhere
« Last Edit: November 22, 2007, 03:59:05 PM by ambulancevoice »
Open Your Mouth, Heres Your Money

DWBH

Re: ZVEX BOX OF METAL
« Reply #24 on: November 22, 2007, 04:34:27 PM »
I've heard it's CMOS-based.


























Nah, just kidding.

gez

Re: ZVEX BOX OF METAL
« Reply #25 on: November 22, 2007, 06:31:41 PM »
smd resistors have more noise than truhole Rs

Can you point me to some evidence/figures to back this up?  I ask as I use metal-film SMD resistors and haven't had any problems/can't tell the difference.

Not having a go at you, just curious...
« Last Edit: November 22, 2007, 06:33:38 PM by gez »
"They always say there's nothing new under the sun.  I think that that's a big copout..."  Wayne Shorter

12afael

Re: ZVEX BOX OF METAL
« Reply #26 on: November 22, 2007, 08:25:03 PM »
this is my source:
http://www.prodigy-pro.com/forum/viewtopic.php?t=9035&highlight=resistor+smd+noise

maybe your metal film smd are good enought.

gez

Re: ZVEX BOX OF METAL
« Reply #27 on: November 23, 2007, 04:31:50 AM »
this is my source:
http://www.prodigy-pro.com/forum/viewtopic.php?t=9035&highlight=resistor+smd+noise


His 'research' is meaningless as he hasn't necessarily compared like with like: different conductive ceramics are used from manufacturer-to-manufacturer in the making of film resistors.  A lot of problems people have with noise in surface-mount circuits is poor layout; hardly surprising when considering how closely packed components can be.  I'm sorry, but I'm not convinced.

Quote
maybe your metal film smd are good enought.

No, there's no difference.  'Good enough' is for audiophiles!  :icon_lol:
"They always say there's nothing new under the sun.  I think that that's a big copout..."  Wayne Shorter

12afael

Re: ZVEX BOX OF METAL
« Reply #28 on: November 23, 2007, 12:27:30 PM »
I don`t have access to SMD resistors. why don`t you make a test?, some heat and current is what you need.
did you measure your noise floor or just a listen test?

Quote
Contact noise is dependent on both average DC current and resistor material/size. The most significant contributor to noise in guitar amplifiers is the use of low-wattage carbon composition resistors. Since the noise is proportional to resistor size, the use of 2W carbon comp resistors will improve the performance over that of 1/2W resistors. Studies have shown a factor of 3 difference between a 1/2W and a 2W carbon comp resistor operating at the same conditions. -aikenamps.com

and here check page 12.
http://industrial.panasonic.com/www-data/pdf/AOA0000/AOA0000PE8.pdf

the size issue have sense for me.

gez

Re: ZVEX BOX OF METAL
« Reply #29 on: November 23, 2007, 01:01:06 PM »
I don`t have access to SMD resistors. why don`t you make a test?, some heat and current is what you need.
did you measure your noise floor or just a listen test?

Quote
Contact noise is dependent on both average DC current and resistor material/size. The most significant contributor to noise in guitar amplifiers is the use of low-wattage carbon composition resistors. Since the noise is proportional to resistor size, the use of 2W carbon comp resistors will improve the performance over that of 1/2W resistors. Studies have shown a factor of 3 difference between a 1/2W and a 2W carbon comp resistor operating at the same conditions. -aikenamps.com

and here check page 12.
http://industrial.panasonic.com/www-data/pdf/AOA0000/AOA0000PE8.pdf

the size issue have sense for me.

I think we're at cross-purposes here.  The majority of circuits that get built round here are low power (not amps) and in said circuits, noise really isn't going to be an issue.  Therefore, it's not a great idea to use blanket rules like 'all SMD resistors are noisy'.  From the panasonic guide you linked to:


From Fig.14, a noise level tends to become large, so that form becomes small.
Therefore, in the circuit that attaches importance to the noise-characteristic, chip
resistor of large shape or thin-film chip resistor is recommended.


I use 1206, which are the largest.  No idea if they're 'thin-film' but there really is no difference in noise.  As I design my own stuff, it all gets breadborded beforehand using thru-hole metal-film resistors.  There really is no difference/increase in noise.  As it's never been a problem, why would I do testing??
« Last Edit: November 23, 2007, 01:03:14 PM by gez »
"They always say there's nothing new under the sun.  I think that that's a big copout..."  Wayne Shorter

Mark Hammer

Re: ZVEX BOX OF METAL
« Reply #30 on: November 23, 2007, 01:26:37 PM »
A lot of problems people have with noise in surface-mount circuits is poor layout; hardly surprising when considering how closely packed components can be. 
Cogent point.  A more valid comparison would be a well-designed through-hole layout in comparison with a surface mount identical equivalent.  That is, the only thing different would be the use of a surface mount component in the same spot that a through-hole was used.  Same board size, same spacing, same location and circuit trace size, etc.

The other thing one wonders about is whether, in the event that reliable measurements of greater noise levels do exist, what role the fabrication techniques themselves might have, and whether the quality control of SMD components matches that of through-hole.  In other words, it may be entirely possible to poorly assemble a surface-mount circuit that is:
a) poorly laid out or too closely spaced,
b) abused during the assembly process,
c) made of components that are not consistently up to spec.

These are by no means accusations or even anything I can empirically support.  Just trying to make the point that some of the assertions being made may stem from circumstances of use, not anything endemic to SMD-style components.  If so, all one has to do is identify the less hospitable circumstances, and avoid them.  You will note, as well, that passive SMD components come in a wide variety of shapes and sizes (as through-holes do), and some of the discussion on the Prodigy forum clearly notes differences in noise specs as a function of size/format.  Indeed, one poster even notes that 1/8 through-hole resistors fare worse than 1/4w.

Now, while I do not wish to disparage audiophiles, it IS fairly clear that there is a tradition in many circles of being biased towards older technology.  Such biases are not entirely without substance (and the Prodigy discussion IS based around objective measurements), but as we saw with the introduction of digitally produced and reproduced sound, sometimes audiophiles mistake what something sounds like when done poorly, with how it would sound when done properly.

Behringer has been able to churn out inexpensive clones of Boss pedals, and Danelectro has been able to churn out even cheaper clones of other pedals, using surface-mount technology.  On occasion, people have commented on additional noise, but my sense is that this has sometimes arisen because of poor choice in components.  My Behringer AC-2 clone is quite noisy, but when I took it apart I saw they went with TL064 equivalents, rather than the less noisy TL074 or M5218L used in the original.  Yes, it's a surface-mount clone, but no it is not the exact same circuit.

I'm confident Zachary Vex realizes that for the price-point he aims at, and for the clientele he values, there is an expectation of consistently noise-free performance.  When those expectations are unlikely to be met, he even builds it into the name (Junky Lo-Fi Loop), as if to emphasize the reasonable expectations of low noise in the other products.

12afael

Re: ZVEX BOX OF METAL
« Reply #31 on: November 23, 2007, 03:22:13 PM »
you are right provably on a guitar pedal you will not notice a difference in noise , that not mean it doesn`t exist. I`m very shure that there is a difference, worst or better, it depende of a lot of factors. 

kugua

Re: ZVEX BOX OF METAL
« Reply #32 on: February 11, 2008, 08:11:17 AM »
maybe someone open it?or gut shot, :icon_wink:sound great.waiting for message
no

Paul Perry (Frostwave)

Re: ZVEX BOX OF METAL
« Reply #33 on: February 11, 2008, 08:25:42 AM »
If it is done correctly, surface mount could give LESS noise. At least, it could be less prone to interference pickup - because the interference pickup is due to parts of the circuit acting as receiving antennas, and with surface mount, you naturally have a smaller "antenna".  Similiarly for radiating noise.
And, while you might think that being closer together will encourage pickup between various sections, the fact is that parallel traces - where this is prone to occur - are naturally shorter, so the mutual inductance may well be less.
For the average - and not-so-average - FX box, the noise floor isn't set by the resistors (unless someone is trying for a little extra mojo by using comp resistors rescued from a WW2 radio!). It's set by transistors & interference via leads & power supply.

Renegadrian

Re: ZVEX BOX OF METAL
« Reply #34 on: March 20, 2010, 07:45:59 PM »
My attempt with the ZVEX BOX OF METAL layout not verified yet but triple checked...Tried to fit everything in the smallest way, still that vero is larger then your ordinary project...THX to MADBEAN for his schematic and BoM.


Done an' workin'=Too many to mention - Tube addict!

PedroTejada

Re: ZVEX BOX OF METAL
« Reply #35 on: March 21, 2010, 01:56:20 AM »
I found those links on a Brazilian forum a while ago:
http://....org/members/bajaman/Baja/Vzex/MoxofBetalGatesketch.jpg
http://....org/members/bajaman/Baja/Vzex/MoxofBetalfirstsketch.jpg
http://....org/members/bajaman/Baja/Vzex/Moxofbetaloverlay.png
http://....org/members/bajaman/Baja/Vzex/Moxofbetaltop.png
http://....org/members/bajaman/Baja/Vzex/Moxofbetalbottom.png

I'm not aware of anyone who tested those PCBs or the schem. I know that some guys on this forum routed a PCB without the gate knob, but I can't find it anymore... Anyway, I'm not going to build it... The BOM is the only Z.Vex Pedal that I didn't like!
Brazilian Weekend Builder :D

Renegadrian

Re: ZVEX BOX OF METAL
« Reply #36 on: March 21, 2010, 07:11:40 AM »
You can find the works of bajaman and madbean in a dedicated topic at FSB forum.
As I was asked to build one I figured I wanted to have a personal layout using vero.
Done an' workin'=Too many to mention - Tube addict!

Renegadrian

Re: ZVEX BOX OF METAL
« Reply #37 on: May 03, 2010, 06:54:45 PM »
updated version - found a little error in the output wiring  :icon_redface:

Some bizzarre things I realized: The volume never turns down to zero...And the mid is reversed, so clockwise are scooped, also treble pot isn't that effective...

« Last Edit: May 03, 2010, 06:58:59 PM by Renegadrian »
Done an' workin'=Too many to mention - Tube addict!

therecordingart

Re: ZVEX BOX OF METAL
« Reply #38 on: May 03, 2010, 10:35:26 PM »

WGTP

Re: ZVEX BOX OF METAL
« Reply #39 on: May 03, 2010, 11:29:15 PM »
2 examples of nice work. 

I know this is weird, but I have had much better success with Mosfets than Jfets.  Must be my aura or something.

Anyway, If you look here, Joe indicates that the P channel BS250 is inherently quieter than the N channel BS170.  Looks like that might be helpful with this project...   :icon_cool:

http://www.diystompboxes.com/analogalchemy/sch/obsidian.html
Stomping Out Sparks & Flames