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dgatwood
is out. Leave a message.
Sure. It could be infrared too! But those are hard to see
Yeah, I was intentionally spelling ultraviolet as two words as a joke, as if to imply that it was a particular shade of violet, much like "ultra suede".
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Brad McGowan
New member
EQ hum solution for ACMP73
Hi all,
I just posted this over on Gearslutz and thought some of you may be interested here as well.
After some considerable time and effort, I have found a reasonable shielding solution that reduces the ACMP73 hum (gain at 80dB and output at max, when the EQ is engaged and 360Hz is selected) by about 10dB. The steady state residual hum is now at what I would call acceptable levels for most professional use. When monitoring at typical levels using nearfield speakers, the hum is inaudible. If you would like to find out more about my proposed fix feel free to visit me on Myspace or over on Gearslutz. Or you can send me a PM, although I may be a little slow responding to those.
I have some plots to post that show the noise improvement for the ACMP73. See below for those.
The first picture shows the response of the line input of ACM73 with gain at 80dB and output level at max. The EQ is disengaged. The white response is the steady state noise of my audio interface. In all pics the red represents the ACMP73.
The second picture shows the response when the EQ is engaged and 360Hz is selected on the mid band. This frequency selection yields the greatest amount of hum regardless of boost or cut setting so it is used as the hum benchmark.
The third picture shows the response after the shielding fix is in place. The hum is not entirely gone but is greatly reduced and is inaudible for practical purposes especially when compared to noise floor of the EQ-out state.
Brad
Hi all,
I just posted this over on Gearslutz and thought some of you may be interested here as well.
After some considerable time and effort, I have found a reasonable shielding solution that reduces the ACMP73 hum (gain at 80dB and output at max, when the EQ is engaged and 360Hz is selected) by about 10dB. The steady state residual hum is now at what I would call acceptable levels for most professional use. When monitoring at typical levels using nearfield speakers, the hum is inaudible. If you would like to find out more about my proposed fix feel free to visit me on Myspace or over on Gearslutz. Or you can send me a PM, although I may be a little slow responding to those.
I have some plots to post that show the noise improvement for the ACMP73. See below for those.
The first picture shows the response of the line input of ACM73 with gain at 80dB and output level at max. The EQ is disengaged. The white response is the steady state noise of my audio interface. In all pics the red represents the ACMP73.
The second picture shows the response when the EQ is engaged and 360Hz is selected on the mid band. This frequency selection yields the greatest amount of hum regardless of boost or cut setting so it is used as the hum benchmark.
The third picture shows the response after the shielding fix is in place. The hum is not entirely gone but is greatly reduced and is inaudible for practical purposes especially when compared to noise floor of the EQ-out state.
Brad
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mshilarious
Banned
Is there some general rule that any product or service related to the group buy may be freely spammed on this board? If so, can I play too? I'll sell you a line-level microphone with -10dBV/Pa sensitivity which gets around the hum problem by increasing SNR with a hot signal 
Otherwise, how about paying for ads the way the rest of the reputable businesses in the world have to?
Or if I am mistaken and your aim is altruistic, why not share your solution and sources with the general public?
Otherwise, how about paying for ads the way the rest of the reputable businesses in the world have to?
Or if I am mistaken and your aim is altruistic, why not share your solution and sources with the general public?
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Brad McGowan
New member
Hi,
I sincerely apologize if I've broken a rule. If the community feels that I am in violation of something then perhaps a moderator could delete the information I've shared thus far.
I do know that there are some folks unhappy with the performance of the units they've purchased and thought they would be interested in knowing that they can do something about it with minimal fuss. I'm sure at some point there may be a solution supported by the warranty of TNC. However, for those users in need of an immediate solution, especially those that don't have the time to become an electronics expert or the resources to tinker, feel free to contact me. I wish the materials I've found to work were cheap (or free) but they are not. And I wish I had more free time and energy to be altruistic, but my time and knowledge is valuable like everyone else's. I'm just trying to help people out and be meagerly compensated for my time and efforts so that I can pay for the pile of unsuccessful shielding attempts sitting on my living room floor.
I apologize to the group if I've offended anyone.
sincerely,
Brad
I sincerely apologize if I've broken a rule. If the community feels that I am in violation of something then perhaps a moderator could delete the information I've shared thus far.
I do know that there are some folks unhappy with the performance of the units they've purchased and thought they would be interested in knowing that they can do something about it with minimal fuss. I'm sure at some point there may be a solution supported by the warranty of TNC. However, for those users in need of an immediate solution, especially those that don't have the time to become an electronics expert or the resources to tinker, feel free to contact me. I wish the materials I've found to work were cheap (or free) but they are not. And I wish I had more free time and energy to be altruistic, but my time and knowledge is valuable like everyone else's. I'm just trying to help people out and be meagerly compensated for my time and efforts so that I can pay for the pile of unsuccessful shielding attempts sitting on my living room floor.
I apologize to the group if I've offended anyone.
sincerely,
Brad
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dgatwood
is out. Leave a message.
Payment problem
I'm not sure if my payment went through or not. I guess I had the window open too long before clicking the payment button. After clicking to complete the transaction, it presented me with a group buy login screen again. Upon logging back in, the user console says I haven't paid.
I'm not sure if my payment went through or not. I guess I had the window open too long before clicking the payment button. After clicking to complete the transaction, it presented me with a group buy login screen again. Upon logging back in, the user console says I haven't paid.
mshilarious
Banned
There are rules here, but practically no moderation at all. So my sole recourse is to heckle you, which is what I am doing. I don't see how your time being valuable equates to free exposure for your products. You wanna make money, man up and pay for ads
My time is valuable too, and you owe me $0.02 for the page view 
BudgetMC
Spread the Love, People!
I, for one, applaud Brad's offer. Doesn't look like he's charging an exorbitant amount for the fix. This whole "group buy" is something of a communal undertaking, and it looks like he's just offering to contribute to
Goodness knows various manufacturers and modders of mics make their products and services known on this board... doesn't seem to me, at least, that Brad is acting differently.
Goodness knows various manufacturers and modders of mics make their products and services known on this board... doesn't seem to me, at least, that Brad is acting differently.
pohaku
New member
While I generally prefer that commercial endeavors be prohibited on the Board, in this particular instance, I'm pretty comfortable with Brad's offer here. This is an issue for lots of us that have bought these units. Some of us are competent with a soldering iron and I suspect that many are not. This really isn't a commercial product with wide application -- it's pretty GB specific. In this case, a member of the GB has spent some time diagnosing and solving a problem that many of us GB members either have or will have (still got 3 red noes here). Given the communal nature of the GB, I personally would like to thank Brad for his effort and making his "fix" available to us. Beats the hell out of figuring it out myself. I'm waiting to hear how it works out for the 84s and 81s. I have a total of 6 of them coming to me and I expect that they will need some fixin.
Thanks Brad!
Thanks Brad!
mshilarious
Banned
Contribute to, or profit from? I saw a post on GS about somebody offering to sell a unit they had fixed for only "a little" more than the cost of the unit + parts. How is that a communal venture? I don't want that kind of crap here.
Which would those be? I mean, who make posts announcing new product offerings? I can only think of one, and it's equally gauche.
And who among those refuses to disclose their product details? Heck, today I just gave away the entire circuit to a product I haven't even launched yet. I think the answer to that speaks to those are participating in a communal undertaking (which I read as open source), and those who are solely seeking a profit.
crazydoc
Master Baiter
I think in the spirit of this forum, and in the spirit of the group buy, that Brad could make his procedures known for those that are comfortable with DIY. Those that want a fix-in-a-box are free to purchase his product.
Of course, Brad's not really a member here, so I wouldn't expect any altruistic offerings from him, and I'd say that, by the same token, if he wants to sell something here, that he purchase advertising instead of taking advantage of (spamming) this free bbs.
Of course, Brad's not really a member here, so I wouldn't expect any altruistic offerings from him, and I'd say that, by the same token, if he wants to sell something here, that he purchase advertising instead of taking advantage of (spamming) this free bbs.
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donkeystyle
New member
ten characters
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Brad McGowan
New member
I have a user account here, although I don't spend much time posting here, which should be obvious from my low post count. I usually hang out on Gearslutz. And many of you may know me from there. And some of you hopefully know the quality of my posting contributions to that forum and therefore have a sense of what kind of person I am.
I thought about it and I would likely have to spend more time answering emails about how to properly construct the shield or fix poorly made ones, than I would just supplying pre-built shields with simple instructions about where to place it. Since my time is valuable like that of many other users of these preamps, I chose to offer a solution that makes the best use of everyone's time.
There have already been a couple posts about buying upgraded transformers and circuit boards on this forum (I'm personally thankful those posts were made because I wouldn't have found out about it otherwise), which would benefit users seeking to upgrade their units. So I didn't think much about making a similar post that would help people improve their preamps. Again I apologize if I'm offending people.
Anyway, I don't want to take up any more bandwidth on this subject. I'd be more than happy to move my posting to another more appropriate part of this forum if someone would be so kind to tell me where the best location is.
Brad
I thought about it and I would likely have to spend more time answering emails about how to properly construct the shield or fix poorly made ones, than I would just supplying pre-built shields with simple instructions about where to place it. Since my time is valuable like that of many other users of these preamps, I chose to offer a solution that makes the best use of everyone's time.
There have already been a couple posts about buying upgraded transformers and circuit boards on this forum (I'm personally thankful those posts were made because I wouldn't have found out about it otherwise), which would benefit users seeking to upgrade their units. So I didn't think much about making a similar post that would help people improve their preamps. Again I apologize if I'm offending people.
Anyway, I don't want to take up any more bandwidth on this subject. I'd be more than happy to move my posting to another more appropriate part of this forum if someone would be so kind to tell me where the best location is.
Brad
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Brad McGowan
New member
ACM-310 mod
In the spirit of goodwill, here's a simple mod I worked out for the ACM-310 microphone that really improves depth, detail, and low and high frequency extension. I had posted this over at Gearslutz about a week ago. I thought I would share with people here as well if you are handy with the soldering iron:
1. Replace the capsule coupling cap with a 1000pF Wima FKP-2.
2. Replace the 0.1uF film cap on the side of the circuit board with a 0.1uF / 100V Wima MKP-2.
3. Replace the stock cable with a Gotham Audio tube mic cable.
Then end result:
- More open top end with greater sense of air and depth.
- More impact and extension in the low end with a greater sense of dynamic realism.
- Increased detail and sense of harmonics throughout midrange.
I also tried replacing the stock 22uF / 25V electrolytic with a Nichicon HE of the same value, and although it extended the low end even further it made the low mids a little thicker than I liked. So I put the stock electrolytic back in.
Total cost of parts: $1 for caps, ~$30 for cable and connectors (or $65 to have Redco make you a 20 footer).
Total time to mod: 30 minutes.
Enjoy!
Brad
p.s. I get a lot of use out of those Naiant line pads to run my mixes through some preamps I built. Great value! Keep up the good work, sir!
In the spirit of goodwill, here's a simple mod I worked out for the ACM-310 microphone that really improves depth, detail, and low and high frequency extension. I had posted this over at Gearslutz about a week ago. I thought I would share with people here as well if you are handy with the soldering iron:
1. Replace the capsule coupling cap with a 1000pF Wima FKP-2.
2. Replace the 0.1uF film cap on the side of the circuit board with a 0.1uF / 100V Wima MKP-2.
3. Replace the stock cable with a Gotham Audio tube mic cable.
Then end result:
- More open top end with greater sense of air and depth.
- More impact and extension in the low end with a greater sense of dynamic realism.
- Increased detail and sense of harmonics throughout midrange.
I also tried replacing the stock 22uF / 25V electrolytic with a Nichicon HE of the same value, and although it extended the low end even further it made the low mids a little thicker than I liked. So I put the stock electrolytic back in.
Total cost of parts: $1 for caps, ~$30 for cable and connectors (or $65 to have Redco make you a 20 footer).
Total time to mod: 30 minutes.
Enjoy!
Brad
p.s. I get a lot of use out of those Naiant line pads to run my mixes through some preamps I built. Great value! Keep up the good work, sir!
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mshilarious
Banned
Here's the thing: there is no appropriate board, or more accurately, no one knows if there is an appropriate board or not. I'll explain.
Personally, I think this entire thread should be in Free Ads, because it's a big giant ad. It so happens Chance is a non-profit seeking dealer. That's complicated--dealer posts aren't allowed in Free Ads, but the non-profit motive seems noble enough. I just don't get why it's in Mics anymore (it started here two years ago when it was just mics). I mean, at least $175K of the last order, and most of the discussion, is about preamps.
The transformer pitch muddies the water quite a lot, you are correct. I imagine Oliver is making a profit. But Oliver hasn't posted here to my knowledge, and Chance doesn't profit from mentioning that Oliver is selling trafos.
Terry and the upgrade kits are even more complicated; Terry is a principal in TNC, but I don't know if these kits involve profit or not.
Chance has inferred that all of this is development for an eventual commercial offering. Or maybe that is overstated. Inferences can be hard to decipher. But at any rate, that hasn't occurred yet.
Back to you and Free Ads. As I said, Free Ads doesn't allow dealer posts. You are a dealer in your own kit, and are therefore prohibited from posting there. Now, if you ask me, there should be dealer posts allowed in Free Ads, or maybe a separate Retail section. But I don't make the rules.
Who makes the rules? Well, Dragon did, but he recently sold the board to the French. After their initial excitement and graphic design changes, I believe we have scared them into inaction. Probably they just want to profit off of ads to recover their investment, and are concerned with not screwing up the community to facilitate that goal.
So there still seems to be nobody to moderate the board. No one will move your post. No moderator will likely even see your post. It's up to every member to adhere to the rules as they may or may not exist. Make your own ethical judgment and stand behind it.
I'd recommend Google Adwords. You will pay about $0.60 for 1,000 page views here.
Personally, I think this entire thread should be in Free Ads, because it's a big giant ad. It so happens Chance is a non-profit seeking dealer. That's complicated--dealer posts aren't allowed in Free Ads, but the non-profit motive seems noble enough. I just don't get why it's in Mics anymore (it started here two years ago when it was just mics). I mean, at least $175K of the last order, and most of the discussion, is about preamps.
The transformer pitch muddies the water quite a lot, you are correct. I imagine Oliver is making a profit. But Oliver hasn't posted here to my knowledge, and Chance doesn't profit from mentioning that Oliver is selling trafos.
Terry and the upgrade kits are even more complicated; Terry is a principal in TNC, but I don't know if these kits involve profit or not.
Chance has inferred that all of this is development for an eventual commercial offering. Or maybe that is overstated. Inferences can be hard to decipher. But at any rate, that hasn't occurred yet.
Back to you and Free Ads. As I said, Free Ads doesn't allow dealer posts. You are a dealer in your own kit, and are therefore prohibited from posting there. Now, if you ask me, there should be dealer posts allowed in Free Ads, or maybe a separate Retail section. But I don't make the rules.
Who makes the rules? Well, Dragon did, but he recently sold the board to the French. After their initial excitement and graphic design changes, I believe we have scared them into inaction. Probably they just want to profit off of ads to recover their investment, and are concerned with not screwing up the community to facilitate that goal.
So there still seems to be nobody to moderate the board. No one will move your post. No moderator will likely even see your post. It's up to every member to adhere to the rules as they may or may not exist. Make your own ethical judgment and stand behind it.
I'd recommend Google Adwords. You will pay about $0.60 for 1,000 page views here.
pohaku
New member
Aren't the transformer and electronics upgrades that TNC has recently offered on this thread a commercial venture? They may be specially developed, and low priced and all, but I had the distinct impression that both they and the Lucas Engineering offerings were commercial offerings that were of interest to folks participating in the GB. Premodded mics are even being offered.
Great Group Buy News!
TNC announce Custom wound transformers for TNC microphones, at Group Buy Special Prices!
TNC have now aranged to offer transformers custom designed and hand wound for specific models of the TNC microphones. Also in the works are drop-in replacement electronics that will be designed to even better utilise the capabilities of the stock capsules, and also to integrate with certain of the custom transformers.
Transformers are designed and manufactured by AMI/TAB-Funkenwerk in Gaylord, Kansas, by Mr. Oliver Archut.
Electronics are being custom designed by Lucas Engineering technicians. They will be manufactured in the USA or the Bahamas, and will be available soon. We will also have available upgraded "pre-modified" microphones in each style, at some point in the near future.
Now, I'm pleased to have the opportunity for these and I'm not knocking TNC for offering, but it seems that this really isn't any different than what Brad has done. It seems that we now have a different type of commercial activity being generated on the Board -- not strictly group buy and not strictly typical commercial market sales -- but rather materials or kits that relate to the GB, developed and sold by GB members, and which are not non-profit - but which are priced way below typical commercial offerings. So what do we want to do about that?
EDIT: Mshilarious - just read your prior post, which you obviously posted while I was writing mine. Yup, it's complicated alright. You are absolutely correct that what was originally an altruistic GB has certainly morphed into something else that has become a square peg in a round hole.
mshilarious
Banned
to have the opportunity for these and I'm not knocking TNC for offering, but it seems that this really isn't any different than what Brad has done. It seems that we now have a different type of commercial activity being generated on the Board -- not strictly group buy and not strictly typical commercial market sales -- but rather materials or kits that relate to the GB, developed and sold by GB members, and which are not non-profit - but which are priced way below typical commercial offerings. So what do we want to do about that?
Well, I guess you could be right there. I thought it was just an Oliver offering. If TNC gets a cut, that's a big problem.
Again, all I want is equity. Can everyone offer commercial items? Or only commercial items that relate to group buy offerings? Why would the group buy enjoy that special privilege? And how do we define a group buy related product? Like I said, if I do a high-output mic designed to overcome ACMP hum, is that a related product?
Where do we set the standard for pricing way below commercial offerings? x% profit margin, or x% of comparable products? If it's profit margin, then we need full disclosure of product costs. Chance did that, at least for the first couple of group buys he published the factory invoice. For pricing, is that an average of comparable products, or the lowest priced comparable product? What if there are no comparable products (as there would not be for an upgrade or repair kit)?
And why limit the commercial offering privilege to group buy members?
That's a can of worms, man. That's really opening the doors to all kinds of stuff . . .
B
Brad McGowan
New member
I think anyone who is offering some type of mod, fix, repair, or upgrade for the Group Buy products should be allowed to make those offerings known to GB participants. I, for one, would love to know about all the options available to me for improving the performance of the tools I just acquired. It's great when it's all in one thread too. It's like one-stop shopping. Then it saves having to track down information all across the internet. I would totally welcome any kind of microphone or preamp mod you might come up with! I'm sure others would as well. If you wanted to offer your electronics know-how to perform ACMP81 repairs I'm sure you'd have no shortage of takers. I'd probably even consider sending mine in just to save myself the hassle.
Which preamps and mics did you end up buying, by the way?
The idea that any of this is not for profit seems comical to me. I would really hope Chance is earning some money to pay off his house which surely took a dive in value over the last year.
Brad
Which preamps and mics did you end up buying, by the way?
The idea that any of this is not for profit seems comical to me. I would really hope Chance is earning some money to pay off his house which surely took a dive in value over the last year.
Brad
G
Gilliland
New member
Brad, are there other manufacturers than Wima that would be equivalent in quality/purpose here? I ask because I have an electronics surplus store near me that carries a lot of parts, but not necessarily every value or brand. If I have a list of alternatives, I'm more likely to find what I need.
Thanks for this information, btw. I have four of the 310s, and I like them a lot - even unmodded. But I'm not afraid to tinker with them either.
mshilarious
Banned
Why the special privilege? Does not make sense to me. If you profit, why should the board owners not profit? Buy an ad.
I have less than zero desire to do that. zmix is a better tech anyway. Plus, honestly, I wouldn't touch that with a thirty foot pole, due to liability issues. I'm not insured for that. Are these things UL listed? Realistically, it would probably take not only shielding the inductors and replacing those transistors, but also moving the power transformer to an external box. Also, the gain circuit apparently needs a major revision. Tech time + parts for that would be more than the cost of the preamp.
I think the only piece of gear I've bought in the last three years was a third UAD-1 card. And I never even bought the Neve EQ plugs, because I don't like them as much as the Pultec or Helios.
Yeah, it would be really funny if this was all for profit, and got two years and millions of page views for free. You're a laugh riot.
I think I have a higher opinion of Chance than that . . .
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