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Post by EmRR on Jan 6, 2017 12:27:56 GMT -6
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ericn
Temp
Balance Engineer
Posts: 15,011
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Post by ericn on Jan 6, 2017 13:17:02 GMT -6
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Post by EmRR on Jan 6, 2017 13:45:42 GMT -6
Yep that's a steal. I guess only advantage of the Middle Atlantic is it's scored for several genders, so you can mix and match or skip slots as you want, if you need to use Switchcraft patterns.
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Post by Ward on Jan 6, 2017 14:32:37 GMT -6
Not just about ribbons. Preamps too. Patron saint of Elco too.
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Post by johneppstein on Jan 8, 2017 16:34:43 GMT -6
John Eppstein: Founder of Ribbon Protectors of America Thanks, but I'm not the founder. I didn't originate that by a long shot...
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Post by EmRR on Jan 11, 2017 10:25:31 GMT -6
...and here's the other end going back in.
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Post by Quint on Dec 31, 2017 19:31:54 GMT -6
I've been following the Flock thread recently, and phantom power in a patchbay came up again. Anyway, that led to me randomly circling back to this thread.
Something that never got mentioned in this thread is 500 series preamps (or other preamps without a dedicated line input) which have a switch allowing for running line input signals into the preamp. Preamps with mic/line switches (and only ONE input point) to accommodate line inputs for adding color are common these days. It would take some pretty complicated wiring to NOT have those kind of preamps wired up in a TT patchbay.
For those of you advocating for an XLR bay for mic inputs, how are also accommodating for line input into those preamps which do not have a second input for line level?
I have all of my preamps (inputs and outputs) wired to TT patchbays to allow for this, but I also exclusively use external phantom power supplies to specifically avoid EVER using the phantom power on my preamps and the potential issues that could arise by doing so through a TT patchbay.
I'm just curious how some of you XLR mic bay guys are accommodating line level through your preamps?
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Post by drbill on Dec 31, 2017 20:16:57 GMT -6
I've been following the Flock thread recently, and phantom power in a patchbay came up again. Anyway, that led to me randomly circling back to this thread. Something that never got mentioned in this thread is 500 series preamps (or other preamps without a dedicated line input) which have a switch allowing for running line input signals into the preamp. Preamps with mic/line switches (and only ONE input point) to accommodate line inputs for adding color are common these days. It would take some pretty complicated wiring to NOT have those kind of preamps wired up in a TT patchbay. For those of you advocating for an XLR bay for mic inputs, how are also accommodating for line input into those preamps which do not have a second input for line level? I have all of my preamps (inputs and outputs) wired to TT patchbays to allow for this, but I also exclusively use external phantom power supplies to specifically avoid EVER using the phantom power on my preamps and the potential issues that could arise by doing so through a TT patchbay. I'm just curious how some of you XLR mic bay guys are accommodating line level through your preamps? This very issue has caused me to build a "tracking" rack that is separate from my mixing / processing gear. Because $#!@ happens and my accessibility to great tech's is limited where I'm living now!!! It's really easy to do : it's dark, you're tired, you patch wrong, you miss a row, and boom.....the magic smoke is allowed to leave a piece of your beloved outboard collection. You are absolutely right - there IS danger involved. (Danger for your gear and pocketbook at least.) For instance, I'm 90% sure the vp28 (which has line and mic input modes) does indeed pass 48v when line is engaged if in fact the 48v switch is depressed (I MIGHT be wrong, but I don't think so, and I'm away from the studio right now....). Danger. Be careful swapping back and forth between mic and line modes if it's in your TT bay. The AML1073's have a separate line input, so that is a relief for me. They are the ONLY mic amps I leave in the "mixing" racks. The Chroma shares inputs as the vp28 does, but when you switch to "line", 48v is defeated. Brad and I spent a lot of time thinking this over - trying to mitigate "mistakes" from happening. HOWEVER, this does not account for someone hard patching it in when in MIC mode with 48v on. Eventually, I will have enough for both line / mix / processing duties, and mic pre duties - and I will keep them separate. USER RESPONSIBILITY is the only sure fire cure for those types of modules, and unfortunately, as I mentioned above......$#!@ happens. For those using them for mixing/processing and/or for dynamics-ribbons only, Chroma's 48v has a system wide defeat jumper on the PCB and you end up with a mic pre / line processor with no dangerous 48v even if 48v is depressed cause you like the red color - if you prefer it. This is a solution we came to and it HELPS, but it does not solve the possible dangers. If you're using tube mics, dynamics and ribbons though, it fixes the problem. Secondary or separate Mic / Line inputs - which are rare on 500 series of course unless they are 2 spaces or more, are the way to go. The Silver Bullet has these and it mitigates the dangers. Alternately, potentially doubling up on gear and having a tracking rack that does not have mic lines coming up in the bays like I mentioned is the way to go if you can afford it. FOR ME - mic inputs NEVER, EVER, EVER come up on a TT patch bay. There is either an XLR patch bay or patch panel behind the desk for switching mic lines. It's those "dual duty" units that cause issues, and they are quite capable of allowing the sacred smoke to exit your converters, gear, etc..
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Post by Quint on Dec 31, 2017 20:32:40 GMT -6
I've been following the Flock thread recently, and phantom power in a patchbay came up again. Anyway, that led to me randomly circling back to this thread. Something that never got mentioned in this thread is 500 series preamps (or other preamps without a dedicated line input) which have a switch allowing for running line input signals into the preamp. Preamps with mic/line switches (and only ONE input point) to accommodate line inputs for adding color are common these days. It would take some pretty complicated wiring to NOT have those kind of preamps wired up in a TT patchbay. For those of you advocating for an XLR bay for mic inputs, how are also accommodating for line input into those preamps which do not have a second input for line level? I have all of my preamps (inputs and outputs) wired to TT patchbays to allow for this, but I also exclusively use external phantom power supplies to specifically avoid EVER using the phantom power on my preamps and the potential issues that could arise by doing so through a TT patchbay. I'm just curious how some of you XLR mic bay guys are accommodating line level through your preamps? This very issue has caused me to build a "tracking" rack that is separate from my mixing / processing gear. Because $#!@ happens and my accessibility to great tech's is limited where I'm living now!!! It's really easy to do : it's dark, you're tired, you patch wrong, you miss a row, and boom.....the magic smoke is allowed to leave a piece of your beloved outboard collection. You are absolutely right - there IS danger involved. (Danger for your gear and pocketbook at least.) For instance, I'm 90% sure the vp28 (which has line and mic input modes) does indeed pass 48v when line is engaged if in fact the 48v switch is depressed (I MIGHT be wrong, but I don't think so, and I'm away from the studio right now....). Danger. Be careful swapping back and forth between mic and line modes if it's in your TT bay. The AML1073's have a separate line input, so that is a relief for me. They are the ONLY mic amps I leave in the "mixing" racks. The Chroma shares inputs as the vp28 does, but when you switch to "line", 48v is defeated. Brad and I spent a lot of time thinking this over - trying to mitigate "mistakes" from happening. HOWEVER, this does not account for someone hard patching it in when in MIC mode with 48v on. Eventually, I will have enough for both line / mix / processing duties, and mic pre duties - and I will keep them separate. USER RESPONSIBILITY is the only sure fire cure for those types of modules, and unfortunately, as I mentioned above......$#!@ happens. For those using them for mixing/processing and/or for dynamics-ribbons only, Chroma's 48v has a system wide defeat jumper on the PCB and you end up with a mic pre / line processor with no dangerous 48v even if 48v is depressed cause you like the red color - if you prefer it. This is a solution we came to and it HELPS, but it does not solve the possible dangers. If you're using tube mics, dynamics and ribbons though, it fixes the problem. Secondary or separate Mic / Line inputs - which are rare on 500 series of course unless they are 2 spaces or more, are the way to go. The Silver Bullet has these and it mitigates the dangers. Alternately, potentially doubling up on gear and having a tracking rack that does not have mic lines coming up in the bays like I mentioned is the way to go if you can afford it. FOR ME - mic inputs NEVER, EVER, EVER come up on a TT patch bay. There is either an XLR patch bay or patch panel behind the desk for switching mic lines. It's those "dual duty" units that cause issues, and they are quite capable of allowing the sacred smoke to exit your converters, gear, etc.. A jumper within all preamps to disable phantom would be great, but obviously nearly all of them don't have this option. I've considered disabling the phantom on all of my preamps. It shouldn't be too hard to do but I'd have to inquire about the best way to do that with the maker of each of the preamps I own. Alternatively, as I mentioned, I simply just don't EVER use the phantom on my preamps and use an external phantom supply between the preamps and mics. I can't afford a separate tracking rack with duplicate preamps. A lot of the preamps I've bought we're specifically chosen BECAUSE they could handle selectable line level. The external phantom supply has been the best option for me so far. I suppose that provides me the same level of safety and functionality as you achieve with your "tracking" rack. But I'd still be interested in outright disabling phantom on all of my preamps if it wasn't too much of a pain in the ass. I'm still curious to hear how other people are handling this scenario though? Single input preamps which can accept line level create a bit of a conundrum....
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Post by jeremygillespie on Dec 31, 2017 20:59:35 GMT -6
I just don’t miss patches...
I know this is an unpopular opinion - but, check for phantom before you make or remove a patch. That simple.
Every SSL console has mic lines in the bay. Every studio in the north east I’ve been in is setup this way. Hell, there are Neve consoles where phantom is ALWAYS on. You can’t turn it off.
Every single move you make in a control room should be deliberate. It’s when you start to get ahead of yourself and do things willy nilly that mistakes can happen.
I can check tomorrow if my VP-28’s pass phantom when in line mode. Best advice would be, don’t turn on phantom when you’re in line mode 😁
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Post by Quint on Dec 31, 2017 21:13:35 GMT -6
I just don’t miss patches... I know this is an unpopular opinion - but, check for phantom before you make or remove a patch. That simple. Every SSL console has mic lines in the bay. Every studio in the north east I’ve been in is setup this way. Hell, there are Neve consoles where phantom is ALWAYS on. You can’t turn it off. Every single move you make in a control room should be deliberate. It’s when you start to get ahead of yourself and do things willy nilly that mistakes can happen. I can check tomorrow if my VP-28’s pass phantom when in line mode. Best advice would be, don’t turn on phantom when you’re in line mode 😁 Even if an external preamp like the VP28 doesn't pass phantom when in line mode, what if you forget to turn off the phantom before you switch over to the line input? The patchbay doesn't know or care whether the preamp is in mic or line mode. I get that a lot of consoles have mic inputs in the patchbay and that a lot of you are saying that it doesn't matter as long as the mics upstream of the console can handle phantom even if they're not condensers. That's not the topic I was asking about though. The preamps in these bespoke consoles aren't being utilized in a line level input fashion like some external preamps are. That was the focus of my earlier post. That's where the danger really lies.
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Post by drbill on Dec 31, 2017 21:18:02 GMT -6
I just don’t miss patches... I know this is an unpopular opinion - but, check for phantom before you make or remove a patch. That simple. Every SSL console has mic lines in the bay. Every studio in the north east I’ve been in is setup this way. Hell, there are Neve consoles where phantom is ALWAYS on. You can’t turn it off. Every single move you make in a control room should be deliberate. It’s when you start to get ahead of yourself and do things willy nilly that mistakes can happen. I can check tomorrow if my VP-28’s pass phantom when in line mode. Best advice would be, don’t turn on phantom when you’re in line mode 😁 When on a Neve, what do you do when you patch your D/A into the mic/line in of your desk? ? ? ? Sizzle? Sometimes people want/need to patch into mic inputs from line level outputs. Some of which will sizzle.... I wish I could say I've never missed a patch, or never had a 2nd that has, but alas....not a single person I've ever worked with has been "perfect", with myself at the top of the imperfection list. $#!@ happens. Sooner or later.
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Post by drbill on Dec 31, 2017 21:19:14 GMT -6
This very issue has caused me to build a "tracking" rack that is separate from my mixing / processing gear. Because $#!@ happens and my accessibility to great tech's is limited where I'm living now!!! It's really easy to do : it's dark, you're tired, you patch wrong, you miss a row, and boom.....the magic smoke is allowed to leave a piece of your beloved outboard collection. You are absolutely right - there IS danger involved. (Danger for your gear and pocketbook at least.) For instance, I'm 90% sure the vp28 (which has line and mic input modes) does indeed pass 48v when line is engaged if in fact the 48v switch is depressed (I MIGHT be wrong, but I don't think so, and I'm away from the studio right now....). Danger. Be careful swapping back and forth between mic and line modes if it's in your TT bay. The AML1073's have a separate line input, so that is a relief for me. They are the ONLY mic amps I leave in the "mixing" racks. The Chroma shares inputs as the vp28 does, but when you switch to "line", 48v is defeated. Brad and I spent a lot of time thinking this over - trying to mitigate "mistakes" from happening. HOWEVER, this does not account for someone hard patching it in when in MIC mode with 48v on. Eventually, I will have enough for both line / mix / processing duties, and mic pre duties - and I will keep them separate. USER RESPONSIBILITY is the only sure fire cure for those types of modules, and unfortunately, as I mentioned above......$#!@ happens. For those using them for mixing/processing and/or for dynamics-ribbons only, Chroma's 48v has a system wide defeat jumper on the PCB and you end up with a mic pre / line processor with no dangerous 48v even if 48v is depressed cause you like the red color - if you prefer it. This is a solution we came to and it HELPS, but it does not solve the possible dangers. If you're using tube mics, dynamics and ribbons though, it fixes the problem. Secondary or separate Mic / Line inputs - which are rare on 500 series of course unless they are 2 spaces or more, are the way to go. The Silver Bullet has these and it mitigates the dangers. Alternately, potentially doubling up on gear and having a tracking rack that does not have mic lines coming up in the bays like I mentioned is the way to go if you can afford it. FOR ME - mic inputs NEVER, EVER, EVER come up on a TT patch bay. There is either an XLR patch bay or patch panel behind the desk for switching mic lines. It's those "dual duty" units that cause issues, and they are quite capable of allowing the sacred smoke to exit your converters, gear, etc.. A jumper within all preamps to disable phantom would be great, but obviously nearly all of them don't have this option. I've considered disabling the phantom on all of my preamps. It shouldn't be too hard to do but I'd have to inquire about the best way to do that with the maker of each of the preamps I own. Alternatively, as I mentioned, I simply just don't EVER use the phantom on my preamps and use an external phantom supply between the preamps and mics. I can't afford a separate tracking rack with duplicate preamps. A lot of the preamps I've bought we're specifically chosen BECAUSE they could handle selectable line level. The external phantom supply has been the best option for me so far. I suppose that provides me the same level of safety and functionality as you achieve with your "tracking" rack. But I'd still be interested in outright disabling phantom on all of my preamps if it wasn't too much of a pain in the ass. I'm still curious to hear how other people are handling this scenario though? Single input preamps which can accept line level create a bit of a conundrum.... Quint - excellent solution. IMO, the best idea I've seen. I may employ that. What external 48v supplies do you use?
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Post by Quint on Dec 31, 2017 21:35:28 GMT -6
A jumper within all preamps to disable phantom would be great, but obviously nearly all of them don't have this option. I've considered disabling the phantom on all of my preamps. It shouldn't be too hard to do but I'd have to inquire about the best way to do that with the maker of each of the preamps I own. Alternatively, as I mentioned, I simply just don't EVER use the phantom on my preamps and use an external phantom supply between the preamps and mics. I can't afford a separate tracking rack with duplicate preamps. A lot of the preamps I've bought we're specifically chosen BECAUSE they could handle selectable line level. The external phantom supply has been the best option for me so far. I suppose that provides me the same level of safety and functionality as you achieve with your "tracking" rack. But I'd still be interested in outright disabling phantom on all of my preamps if it wasn't too much of a pain in the ass. I'm still curious to hear how other people are handling this scenario though? Single input preamps which can accept line level create a bit of a conundrum.... Quint - excellent solution. IMO, the best idea I've seen. I may employ that. What external 48v supplies do you use? I use these: Audio Technica CP8506 I started using these originally because I had read that the phantom power in some preamps was underpowered and didn't provide the full 48v, which could reduce headroom, transient pickup, etc. After the fact, I came to the conclusion that these could also provide me an extra degree of safety with phantom power while also allowing me to still wire up everything, including mic inputs, into my TT patchbays. I'm sure there are other makers of quality external phantom supplies, but I've been happy with the Audio Technica.
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Post by drbill on Dec 31, 2017 23:15:47 GMT -6
Quint - excellent solution. IMO, the best idea I've seen. I may employ that. What external 48v supplies do you use? I use these: Audio Technica CP8506 I started using these originally because I had read that the phantom power in some preamps was underpowered and didn't provide the full 48v, which could reduce headroom, transient pickup, etc. After the fact, I came to the conclusion that these could also provide me an extra degree of safety with phantom power while also allowing me to still wire up everything, including mic inputs, into my TT patchbays. I'm sure there are other makers of quality external phantom supplies, but I've been happy with the Audio Technica. Out of production unfortunately.
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Post by Quint on Dec 31, 2017 23:23:17 GMT -6
I use these: Audio Technica CP8506 I started using these originally because I had read that the phantom power in some preamps was underpowered and didn't provide the full 48v, which could reduce headroom, transient pickup, etc. After the fact, I came to the conclusion that these could also provide me an extra degree of safety with phantom power while also allowing me to still wire up everything, including mic inputs, into my TT patchbays. I'm sure there are other makers of quality external phantom supplies, but I've been happy with the Audio Technica. Out of production unfortunately. They where out of production when I bought them. You can still find them out there on eBay. I'm sure other companies still make a similar product. I imagine that, if you had to, you could find someone to build you an external supply. They're pretty simple in design.
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Post by drbill on Dec 31, 2017 23:48:17 GMT -6
Out of production unfortunately. They where out of production when I bought them. You can still find them out there on eBay. I'm sure other companies still make a similar product. I imagine that, if you had to, you could find someone to build you an external supply. They're pretty simple in design. Yes, there are a few floating around. Pretty cheap construction and kind of dubious. Mostly single channel or dual channel. I wouldn't really be interested in kludging a bunch of stomp box sized 48v solutions together. An 8-12 channel single rack space unit would be ideal. Will keep my eyes open for one.....
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Post by Quint on Dec 31, 2017 23:57:54 GMT -6
They where out of production when I bought them. You can still find them out there on eBay. I'm sure other companies still make a similar product. I imagine that, if you had to, you could find someone to build you an external supply. They're pretty simple in design. Yes, there are a few floating around. Pretty cheap construction and kind of dubious. Mostly single channel or dual channel. I wouldn't really be interested in kludging a bunch of stomp box sized 48v solutions together. An 8-12 channel single rack space unit would be ideal. Will keep my eyes open for one..... An 8 channel unit would be awesome. I'm not sure what all you looked at it. The four channel unit is pretty great. IEC plug and all. Seems like a pretty solid phantom supply.and not a stomp box like you're thinking. www.audio-technica.com/cms/electronics/a30ecc9562ce8061/index.html
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Post by drbill on Jan 1, 2018 0:20:47 GMT -6
Yes, there are a few floating around. Pretty cheap construction and kind of dubious. Mostly single channel or dual channel. I wouldn't really be interested in kludging a bunch of stomp box sized 48v solutions together. An 8-12 channel single rack space unit would be ideal. Will keep my eyes open for one..... An 8 channel unit would be awesome. I'm not sure what all you looked at it. The four channel unit is pretty great. IEC plug and all. Seems like a pretty solid phantom supply.and not a stomp box like you're thinking. www.audio-technica.com/cms/electronics/a30ecc9562ce8061/index.htmlI didn't mean they were stomp boxes. I meant that they were about stomp box sized. There are several units out there. But none that really appealed to me. Yes, the one you linked looked cool, but again, discontinued and none on ebay that I saw. Also, for me, 4 is not enough. I don't EVER want to have to crawl behind a rack to rematch cables. And I want the i/o safely up on the bays. I'm going to talk with BradM about this...... Hopefully I can convince him there's a market like the two of us out there.....
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Post by jeremygillespie on Jan 1, 2018 9:11:44 GMT -6
If you guys wanted, you could just buy a bunch of 48v supply’s and hook them up in a 1ru box with xlr punches on the back. Would be as if racking up some vintage modules, but would just be a dedicated phantom box.
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Post by EmRR on Jan 1, 2018 10:22:55 GMT -6
The Crown 4 channel units are solid. Only new thing i see out there is the Rolls rackmount 6 channel, and there are conflicting pics of the connector set on them.
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Post by matt@IAA on Jan 1, 2018 13:10:40 GMT -6
Couldn’t you mount a small 48v psu in a 1 ru and wire it to a common 48v rail with 6.8k resistors going to each xlr input jack? Hm - you’d also need a 1:1 transformer between the xlr in and out, right?
Seems like that could be done for relatively cheap. Most expensive part would be the xlr connectors I think.
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Post by jimwilliams on Jan 1, 2018 13:22:35 GMT -6
My preamps here are protected against phantom spikes and shorts. I use a cross wired pair of zener diodes. Those are 1N752A's at 5.6 volts. A pair cross wired in series from each input to ground PAST the blocking caps will prevent any damaging spikes from exceeding 11 volts. The 7xx series zener diodes have lower stray capacitance than the 4xxx series and provide the lowest distortion specs.
Another common technique are power rectifier diodes run from the inputs to the power rails. That also works but some front ends will still get some damage if hit at the power rails.
I've yet to get a damaged front end in any non-transformer input mic pre design with the clamp zener diodes. It's insurance here.
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Post by EmRR on Jan 1, 2018 13:36:27 GMT -6
Couldn’t you mount a small 48v psu in a 1 ru and wire it to a common 48v rail with 6.8k resistors going to each xlr input jack? Hm - you’d also need a 1:1 transformer between the xlr in and out, right? Seems like that could be done for relatively cheap. Most expensive part would be the xlr connectors I think. no transformer, all are done with cap isolation. but if it's a transformer pre, you don't need the caps. UNLESS IT's A TELEFUNKEN : ). And you need local filter caps, which are also part of any scheme to ramp up/down, along with switches to turn on/off and bleed stray charge off the caps. Jensen white paper covers it well. And. It's not cost effective to build at all. Parts add up to more than anything on the market, new or used.
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Post by Quint on Jan 1, 2018 14:44:06 GMT -6
My preamps here are protected against phantom spikes and shorts. I use a cross wired pair of zener diodes. Those are 1N752A's at 5.6 volts. A pair cross wired in series from each input to ground PAST the blocking caps will prevent any damaging spikes from exceeding 11 volts. The 7xx series zener diodes have lower stray capacitance than the 4xxx series and provide the lowest distortion specs. Another common technique are power rectifier diodes run from the inputs to the power rails. That also works but some front ends will still get some damage if hit at the power rails. I've yet to get a damaged front end in any non-transformer input mic pre design with the clamp zener diodes. It's insurance here. I'm sure that works for preventing preamps from shorting to ground during patching mics. But I was asking about running/patching line level signal into preamps.
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