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Post by BradM on Jun 14, 2017 18:23:01 GMT -6
jsteiger EmRR - I just finished working up a test jig PCB to be able to take measurements. In addtion to some power resistors to load the various power supplies, I added a simple IC unity gain buffer amp, and a constant current BJT emitter follower to the hot input so that I can take unbalanced noise measurements of the audio path. These two subcircuits give me the option to investigate the noise rejection of an IC op amp or a transistor circuit. My thought is this will give some insight into how different circuit topologies might respond to power supply noise in different racks. Thoughts? Brad
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Post by explorer on Jun 16, 2017 10:17:22 GMT -6
Would love to know how well the updated Fredenstein and Lindell power supplies perform - they are at a competitive price point and since theres nothing particularly complex about the designs it seems possible that they are just as good as the competition.
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Post by BradM on Jun 16, 2017 11:12:50 GMT -6
If designing power supplies was simple then there wouldn't be entire text books dedicated to the subject. I bought a Lindell 6-space rack once. I'll be honest. I thought it had very poor construction and its knock-off EDAC connector gripped the card edge way too tightly.
If someone would like to send me their Fredenstein or Lindell for a month, I'd be happy to test them. I am interested in testing something on the budget end of things. Actually I just made an offer on a Bento 6 on Reverb. We'll see what happens.
UPDATE: Bento 6 has been purchased.
Brad
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kcatthedog
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Post by kcatthedog on Jun 16, 2017 14:17:56 GMT -6
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Post by BradM on Jun 16, 2017 22:13:16 GMT -6
BradM - really excited to see your findings. I was going to mention that I just got an email that Studio Logic Sounds is blowing out the Bento10's for $450 but see you've already purchased a "6" I also saw that Midas has just released a super cheap $500 10-space rack www.sweetwater.com/store/detail/L10RackThe upper middle priced IGS Panzer vintageking.com/igs-audio-panzer-500-module-power-supply seems interesting too as it's got 420 ma per slot! Just throwing out ideas (out of curiosity and need as I'm on the verge of buying a new rack!) I scored the Bento 6 for less than $300, and since these racks are only for testing purposes I don't really need a ton of channels. But thanks for the tip! So let's talk about current draw. It seems that current draw is the spec du jour for 500 series racks. A 4A or 5A power supply sounds great on paper, but I want to know what happens when you only load that PSU with 100-300 mA? There are bunch of modules on the market that pull well under 100 mA each. What does the noise/ripple, and regulation performance look like for a supply that's only at 5-20% max load? How does that compare to a supply that's running at 50-70% max load? I don't know and am genuinely curious. Brad |
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Post by 51xAudio on Jun 17, 2017 3:05:57 GMT -6
Current draw isn't all. Since at the beginning there have been a few modules causing problems in some Racks with weak PSUs the marketing hype is now "I do have more power than you for each slot".
In fact most modules need far below 130mA each rail.
Most cheap and weak PSUs don't have current problems anymore, but I (or my customers) observed
- a minimum load to start up working
- problems with inrush current
- problems with unequal loads
- switching noise
- grounding problems
- the real fun starts with interacting stacked SMPS (module SMPS AND Rack SMPS)
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Post by EmRR on Jun 19, 2017 16:26:29 GMT -6
I get the idea noise can run opposite directions with regards to load depending on linear/smps
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Post by BradM on Jun 26, 2017 13:38:41 GMT -6
I just received my Bento 6 rack. It's not the latest and greatest "S" version, however. This is going to be fun. I should have my new test jig boards in hand by the end of the week. I started work on a power rail impedance measurement board, but that's going to take a little more work before I can figure out the best way to test.
I also have a replacement rack on the way from the manufacturer whose rack is making weird noises. Hopefully I just have a defective unit.
Brad
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Post by guitfiddler on Jun 26, 2017 19:56:50 GMT -6
My 500rack is screaming for CAPI and LTL
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Post by drbill on Jun 26, 2017 20:32:47 GMT -6
My 500rack is screaming for CAPI and LTL A very nice combo.  |
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Post by guitfiddler on Jun 26, 2017 20:35:53 GMT -6
My 500rack is screaming for CAPI and LTL A very nice combo. I am holding off to do some more research, however maybe you can give me some of the info. If you were to record drums with Capi or LTL, what opamps and transformers would you use. There are so many variables, but what I have read in the past certain combinations give better results on certain sources. I just need to narrow down those combinations. Dammit Jeff and Brad! You guys are killing me! And you're not helping much either drbill...lol! |
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Post by pfhuck on Jun 26, 2017 21:59:48 GMT -6
A very nice combo. I am holding off to do some more research, however maybe you can give me some of the info. If you were to record drums with Capi or LTL, what opamps and transformers would you use. There are so many variables, but what I have read in the past certain combinations give better results on certain sources. I just need to narrow down those combinations. Dammit Jeff and Brad! You guys are killing me! And you're not helping much either drbill...lol! I ordered my second 511-VPR rack from Jeff yesterday. It was out of stock for awhile, so YAAAAY! Time to build some modules! I also use his power supply. Very solid stuff! No experience here with the LTL offerings. But the CAPI gear is pretty much a no-brainer in my opinion. My 11 space rack is: 1x - VP312 / GAR2520 3x - VP26 / GAR2520 2x - VP26 / GAR918 2x - VP28 / GAR2520 1x - LOLA / GAR918 2x - BT50 litz / GAR1731 Planning on another LOLA for sure! They're great! And another VP26... Then EQ's and Compressors! Go for it! Just get started! It's a fun journey! |
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Post by ChaseUTB on Jun 26, 2017 23:27:16 GMT -6
A very nice combo. I am holding off to do some more research, however maybe you can give me some of the info. If you were to record drums with Capi or LTL, what opamps and transformers would you use. There are so many variables, but what I have read in the past certain combinations give better results on certain sources. I just need to narrow down those combinations. Dammit Jeff and Brad! You guys are killing me! And you're not helping much either drbill...lol! can help you .... he is the right source for this info! |
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Post by drbill on Jun 27, 2017 0:17:56 GMT -6
A very nice combo. I am holding off to do some more research, however maybe you can give me some of the info. If you were to record drums with Capi or LTL, what opamps and transformers would you use. There are so many variables, but what I have read in the past certain combinations give better results on certain sources. I just need to narrow down those combinations. Dammit Jeff and Brad! You guys are killing me! And you're not helping much either drbill...lol! My methods are shifting with the new tools I have available. I've used vp26's and vp28;s to very good affect when recording drums. I can definitely recommend them. I normally use them on snare, OH and toms though. I always go towards Neve's on kick drum and low toms - and sometimes on OH depending on what I'm after. I prefer those over api variants for "low end" sources. All that said, the Chroma's are switchable between API and Neve and I've been moving towards using them with great success. They are working very well for me. With their EQ and colour expansion slot, they are very flexible, and they sound awesome. The ability to switch in and out all these options from my mic pre's is awesome! I'm obviously biased as I was involved in Chroma and the Silver Bullet's development, but I'm happier than ever with what they are bringing to my recordings. You can't go wrong with any of the options you mentioned. |
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Post by BradM on Jun 27, 2017 11:07:30 GMT -6
A very nice combo. I am holding off to do some more research, however maybe you can give me some of the info. If you were to record drums with Capi or LTL, what opamps and transformers would you use. There are so many variables, but what I have read in the past certain combinations give better results on certain sources. I just need to narrow down those combinations. Dammit Jeff and Brad! You guys are killing me! And you're not helping much either drbill...lol! Well, with Chroma the only thing to decide is which Colour module you want to stick in the analog plugin slot. For drums my vote goes to FET Filter, which you can use to do a mud cut at either 330 Hz or 500 Hz. Plus you can get a little hair/saturation by driving the FET input stage. When I track drums I have always historically used API and Neve flavored preamps. Usually API gets used for overheads and toms, and then Neve for kick and snare. That's my personal preference. With Chroma I have both flavors in one box and can now can easily A/B the two tones and pick the best one for the source. Does Chroma actually sound like both an API and Neve preamp? Honestly, I am having a hard time telling a difference between some of the usual suspects and Chroma. It's a badass module. Check out the sound clips I just made of a simple kick/snare loop using Chromas and FET Filter. Specifically listen to the snare track. FET Filter was doing most of the heavy lifting there. I achieved that sound using two knobs. There's a lot of flexibility and power in this thing: store.louderthanliftoff.com/pages/chroma-sound-clipsBrad |
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Post by jcoutu1 on Jun 27, 2017 11:30:57 GMT -6
I am holding off to do some more research, however maybe you can give me some of the info. If you were to record drums with Capi or LTL, what opamps and transformers would you use. There are so many variables, but what I have read in the past certain combinations give better results on certain sources. I just need to narrow down those combinations. Dammit Jeff and Brad! You guys are killing me! And you're not helping much either drbill...lol! Well, with Chroma the only thing to decide is which Colour module you want to stick in the analog plugin slot. For drums my vote goes to FET Filter, which you can use to do a mud cut at either 330 Hz or 500 Hz. Plus you can get a little hair/saturation by driving the FET input stage. When I track drums I have always historically used API and Neve flavored preamps. Usually API gets used for overheads and toms, and then Neve for kick and snare. That's my personal preference. With Chroma I have both flavors in one box and can now can easily A/B the two tones and pick the best one for the source. Does Chroma actually sound like both an API and Neve preamp? Honestly, I am having a hard time telling a difference between some of the usual suspects and Chroma. It's a badass module. Check out the sound clips I just made of a simple kick/snare loop using Chromas and FET Filter. Specifically listen to the snare track. FET Filter was doing most of the heavy lifting there. I achieved that sound using two knobs. There's a lot of flexibility and power in this thing: store.louderthanliftoff.com/pages/chroma-sound-clipsBrad So is the Neve side of the Chroma and Silver Bullet based on the RND stuff, not vintage 1073 style circuits? Most people don't refer to the RND equipment/sound as Neve. |
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Post by BradM on Jun 27, 2017 11:43:54 GMT -6
So is the Neve side of the Chroma and Silver Bullet based on the RND stuff, not vintage 1073 style circuits? Most people don't refer to the RND equipment/sound as Neve. Nope. It's based on vintage stuff. I just happened to discover that I could tweak it to sound like RND (with Silk) as well. Happy accident.  I've got clips up comparing to a 1073LB as well. Brad |
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Post by BradM on Jun 30, 2017 12:43:00 GMT -6
I think I have a problem. I just ordered more racks for my testing. I have an API 500-8B and a Lindell 506 Power Mk2 on the way.
Brad
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Post by wiz on Jun 30, 2017 17:58:20 GMT -6
I think I have a problem. I just ordered more racks for my testing. I have an API 500-8B and a Lindell 506 Power Mk2 on the way. Brad JLM? cheers Wiz |
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Post by BradM on Jun 30, 2017 18:15:27 GMT -6
Is there a JLM rack? I'm not sure it's really popular. I just spoke with a dealer today who said he sells most of Fredenstein, API, and Lindell.
Brad
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ericn
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Post by ericn on Jun 30, 2017 18:30:29 GMT -6
Is there a JLM rack? I'm not sure it's really popular. I just spoke with a dealer today who said he sells most of Fredenstein, API, and Lindell. Brad Not that well known and I think you can only buy them direct. |
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Post by wiz on Jun 30, 2017 18:58:52 GMT -6
Is there a JLM rack? I'm not sure it's really popular. I just spoke with a dealer today who said he sells most of Fredenstein, API, and Lindell. Brad Not that well known and I think you can only buy them direct. True great stuff though! cheers Wiz |
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ericn
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Post by ericn on Jun 30, 2017 19:24:28 GMT -6
Not that well known and I think you can only buy them direct. True great stuff though! cheers Wiz Joe know's stuff and it's very well built! |
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Post by ChaseUTB on Jul 1, 2017 1:17:47 GMT -6
Ballin.. ⛹️ Swish 🗑☄️
23 lunch boxes later .....
Hey RGO... so remember the lunch box binge I went on....please check the classifieds 😂😭😂 I have pm'd some of you the links already 😆😅
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Post by guitfiddler on Jul 2, 2017 5:30:14 GMT -6
Can't wait to hear some conclusions on this thread...I am really diggin the WES Audio gear
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I've got clips up comparing to a 1073LB as well.
