500 series rack chassis? What are my options?

[Brent]

Looking at taking the plunge into the 500 series realm this week. I will be adding 2 maybe 3 modules initially. Any recommendations or caveats as I decide on a chassis?

So far I've come across these. I'm not sure what other options are out there:

Purple Sweet Ten ( extra linking output and internal PS)
API 500VPR ( external PS)
API 500-6b ( internal PS, cheaper initial buy in with only 6 slots)

Thanks

[Snatchman]

Originally Posted by Brent

Looking at taking the plunge into the 500 series realm this week. I will be adding 2 maybe 3 modules initially. Any recommendations or caveats as I decide on a chassis?

So far I've come across these. I'm not sure what other options are out there:

Purple Sweet Ten ( extra linking output and internal PS)
API 500VPR ( external PS)
API 500-6b ( internal PS, cheaper initial buy in with only 6 slots)

Thanks

Hello..There's the OSA, Brent Averill, some DIY racks, and that's all I can think of at the moment..... Good luck

[Brent]

Originally Posted by Snatchman

Hello..There's the OSA, Brent Averill, some DIY racks, and that's all I can think of at the moment..... Good luck

Thanks snatchman. I'll try to look up some specs on these.

[beat.by.bit]

gentlemen,

dont you know if the EMT 259-10N PSU is compatible with these 500s modules or not? can i find any pin-layout info of it somwhere?

thanks

[Brent]

Just noticed that vintage king has a "buy four 500's, get the 500-6b chassis free" deal... very tempting! thumbsup

[Brent]

Looks like the 500-6b doesn't really have enough juice to start slapping some elixir's or avedis M5's into? At 350mA it looks like it would run out of juice pretty quick?

[Kronos147]

Originally Posted by Brent

At 350mA it looks like it would run out of juice pretty quick?

Hmmm, I understand that the module allowance is 130mA. That should be 780mA in the box. How sure are you of the 350mA? I have not read that.

[NathanEldred]

Originally Posted by Kronos147

How sure are you of the 350mA? I have not read that.

It's been one of the most common ongoing debates among 500 series users for the past year or longer on the forums when talking about various 500 racks.

[Brent]

Originally Posted by Kronos147

Hmmm, I understand that the module allowance is 130mA. That should be 780mA in the box. How sure are you of the 350mA? I have not read that.

Originally Posted by NathanEldred

It's been one of the most common ongoing debates among 500 series users for the past year or longer on the forums when talking about various 500 racks.

Sorry the 360mA I found in reference on Nathan's site I think?

500 Series Rack Comparison Chart - Atlas Pro Audio, Inc.

I've been trying to confirm with API that the new boxes are 800mA but I haven't had word from them yet. I can find no specs on their site in regards to this.

[pan60]

i like the metal work on the B.A and the overall construction.
i have a OSA as well, and never had a issues.
i would say if you go API get the Rack: )~ only because if you don't you'll wish you did later.

[Brent]

Originally Posted by pan60

i would say if you go API get the Rack: )~ only because if you don't you'll wish you did later.

Are you referring to space concerns ( you slut) or power concerns? The reason the lunch box has my eye, is the buy 4 components get the rack free promo that vintage king has going.

[Brent]

Looks like Legacy audio posts the numbers for the new lunch box. The PS looks pretty solid!

Legacy Audio - API 500 SERIES 500-6B Features

he API Model 500-6B six position rack is designed to accept many different API "standard" 5.25" X 1.5" modules. This allows an engineer the flexibility of bringing along specialized EQ effects to any situation. The 500-6B comes self-powered, with a rear panel selected AC voltage switch, and a non-removable power cord. The input/output jacks are the two standard patch-bay jacks found in every professional recording console; large frame 1/4" or the "TT" style smaller jack. In addition, the 500-6B is available with XLR jacks. This eliminates the need for special adaptors and custom cables.

The 500-6B comes standard with a +48 volt internal phantom power supply, bussed to pin 15 for the API 512C to access. It must be noted that the 560A series equalizer may use pin 15 for a "direct output" and must be disabled on the 560A circuit board edge connector by cutting a trace. This will eliminate 48 volts from damaging the 560A series equalizers. If in doubt, feel free to contact the factory.

API makes several modules for the 500-6B, such as the 512C mic preamp, the 525 compressor, the 560 Graphic EQ, and the 550B four band EQ. Combinations of these modules make perfect stereo recording packages (two 513C's and two 550B's) or vocalist's box, (one 512C, two EQ's and one 525 compressor).

---

Current production 500-6B power supplies produce an output of 800mA per rail (1600mA total) @ +-16v.

API 550A = 57.5mA +16v rail, 54.2mA -16v rail, 111.7mA total.
API 550B = 57.5mA +16v rail, 54.2mA -16v rail, 111.7mA total.
API 512C = 43.8mA +16v rail, 42.4mA -16v rail, 86.2mA total.
API 560 = 47.1mA +16v rail, 51.4mA -16v rail, 98.5mA total.
API 525 = 72.8mA +16v rail, 90.6mA -16v rail, 163.4mA total.
Avedis MA5 = 75mA +16v rail, 75mA -16v rail, 150mA total.
Avedis E27 = 45mA +16v rail, 45mA -16v rail, 90mA total.

So what does this all mean?
If for example you load up a 500-6B lunchbox with six 512C modules, it would draw 517mA of total current leaving 1083mA of headroom. So using the figures above, even with the most power hungry modules, the 500-6B lunchbox is capable of producing plenty of current so your modules are never starved of power and are always running at optimum performance.

All API, Avedis Audio and Purple Audio modules will work in any configuration with headroom to spare.
FEATURES:

* Power Supply output = 800mA per rail, 1600mA total.
* Holds 6 API Standard Modules
* Long Frame/TT or XLR Jacks Available
* 48 Volt Internal Phantom Power Supply
* Self-Powered, 100 to 250 Volts, 47 to 63 Hz, Switchable
* Rubber Feet & Carrying Handle for Portability
* Rugged Steel Chassis
* Perfect for Vocalist's "Instrument" and Remote Recordin

[Tim Farrant]

The rating of 1600mA of the 6B Lunchbox is incorrect. It's 800mA. The assumption that each rail can deliver 800mA so that makes 1600mA is wrong. Because one rail is positive and the other negative, the current flows from the positive into the negative, one "sources" the current, the other "sinks" it. They do not add together.


Tim.

[Brent]

Originally Posted by Tim Farrant

The rating of 1600mA of the 6B Lunchbox is incorrect. It's 800mA. The assumption that each rail can deliver 800mA so that makes 1600mA is wrong. Because one rail is positive and the other negative, the current flows from the positive into the negative, one "sources" the current, the other "sinks" it. They do not add together.


Tim.

I guess this is the point of confusion. Geoff and Avedis are saying that we need to look at mA per rail and not the combined mA when looking at the 500 series units.. Tim do you happen to know what a lunchbox can handle 'per rail' then? It seems like this information is not revealed anywhere that makes sense to us laymen.

[NathanEldred]

Originally Posted by Brent

I guess this is the point of confusion. Geoff and Avedis are saying that we need to look at mA per rail and not the combined mA when looking at the 500 series units.. Tim do you happen to know what a lunchbox can handle 'per rail' then? It seems like this information is not revealed anywhere that makes sense to us laymen.

It sounds to me like Tim is saying the same thing as Geoff and Avedis. If the 6b is indeed now 800mA per rail, then it is 800mA delivered to the preamps TOTAL based on Tim's expert information. So if that 'per rail' figure is correct (and the 6b has been updated?), then you could power approx:

5 x Buzz Elixirs, or Shadow Hills mono Gama, or Avedis MA5 (or any combo of 5 of those...which all draw around 150mA each). 150mA x 5 = 750mA total, which gets you just under the total power of the 6b. Tim, am I correct?

[Tim Farrant]

Hi Brent,

I was told by API in May 2007 the Lunchbox was to be upgraded to an 800mA power supply. Forget about "rails", it does not really come into the picture. The current flows from the + or - rail to ground or between the two rails, depending on the design of the module itself, (however too much DC current flowing into the rack ground should be avoided IMO). But at the end of the day, the power supply can deliver 800mA whichever way it flows, that's all we need to care about.

Tim.

[Brent]

Originally Posted by NathanEldred

It sounds to me like Tim is saying the same thing as Geoff and Avedis. If the 6b is indeed now 800mA per rail, then it is 800mA delivered to the preamps TOTAL based on Tim's expert information. So if that 'per rail' figure is correct (and the 6b has been updated?), then you could power approx:

5 x Buzz Elixirs, or Shadow Hills mono Gama, or Avedis MA5 (or any combo of 5 of those...which all draw around 150mA each). 150mA x 5 = 750mA total, which gets you just under the total power of the 6b. Tim, am I correct?

I guess this is what I'm trying to find out too. The confusion comes in with the 150mA number, and Avedis and Geoff saying it's not correct to 'add' the 75 per rail to get this number. Yet if I go look at the Avedis E27 it lists ±16 VDC @ 90mA Total as the power requirement... my head is starting to spin

[Brent]

Originally Posted by Tim Farrant

Hi Brent,

I was told by API in May 2007 the Lunchbox was to be upgraded to an 800mA power supply. Forget about "rails", it does not really come into the picture. The current flows from the + or - rail to ground or between the two rails, depending on the design of the module itself, (however too much DC current flowing into the rack ground should be avoided IMO). But at the end of the day, the power supply can deliver 800mA whichever way it flows, that's all we need to care about.

Tim.

Ok so then we DO add the 75 and 75 for each rail?? So we subtract 150 from the available 800 since both are valid just different polarity?

[Tim Farrant]

Originally Posted by NathanEldred

It sounds to me like Tim is saying the same thing as Geoff and Avedis. If the 6b is indeed now 800mA per rail, then it is 800mA delivered to the preamps TOTAL based on Tim's expert information. So if that 'per rail' figure is correct (and the 6b has been updated?), then you could power approx:

5 x Buzz Elixirs, or Shadow Hills mono Gama, or Avedis MA5 (or any combo of 5 of those...which all draw around 150mA each). 150mA x 5 = 750mA total, which gets you just under the total power of the 6b. Tim, am I correct?

That is correct, however I have not tested the Lunchbox at this capacity myself.

[Brent]

Originally Posted by Tim Farrant

That is correct, however I have not tested the Lunchbox at this capacity myself.

Thanks for clearing that up Tim. At the end of the day, I just want to know how many I can stick in the bugger!

For the portability it should be easy enough to add a couple of lower drawing units to compensate for the thirsty ones.

[Tim Farrant]

Originally Posted by Brent

Ok so then we DO add the 75 and 75 for each rail?? So we subtract 150 from the available 800 since both are valid just different polarity?

Who exactly is specifying "75mA per rail" ?

I'll try to explain further. The 500 racks actually have 3 rails, +15, 0V (ground), -15V. For the purposes of this explanation, we will assume current flows from positive to negative. Therefore, current can flow from the +15 rail into ground as well as into the -15V rail. Current can also flow from ground into the -15V rail (because it is more positive than the -15V).

If the module is designed so that 75mA current flows from the positive rail to the negative rail, with none (or very little) flowing into ground, then that module will be drawing 75mA from the power supply.

On the other hand, if 75mA DC current flows from the positive rail into ground AND 75mA from ground into the negative rail, then that module will be drawing 150mA total. This would be the case of a module with a spec of 75mA PER RAIL.

Make sense?

The info on the Legacy page is misleading and incorrect.

[Brent]

Originally Posted by Tim Farrant

Who exactly is specifying "75mA per rail" ?

I'll try to explain further. The 500 racks actually have 3 rails, +15, 0V (ground), -15V. For the purposes of this explanation, we will assume current flows from positive to negative. Therefore, current can flow from the +15 rail into ground as well as into the -15V rail. Current can also flow from ground into the -15V rail (because it is more positive than the -15V).

If the module is designed so that 75mA current flows from the positive rail to the negative rail, with none (or very little) flowing into ground, then that module will be drawing 75mA from the power supply.

On the other hand, if 75mA DC current flows from the positive rail into ground AND 75mA from ground into the negative rail, then that module will be drawing 150mA total. This would be the case of a module with a spec of 75mA PER RAIL.

Make sense?

Well there's the conundrum. How is the average consumer who isn't an electrical engineer suppose to know that stuff? Don't get me wrong Tim, I REALLY appreciate you taking the time to explain this. The problem for 'some' of us consumers is we go to the manufactures website and simply want to know how much the thing is going to draw from my 800mA reserve for example. I mean on your site I can see clearly where it says 150mA is the current draw. That's perfect. That's what I need to know right? thumbsup

Now here is what I started some of the confusion for me. Researching what modules I was going to initially think of buying, I decided to look at how much mA were going to be drawn. These are the quoted specs from manufactures sites. As you can say, the mA is listed per rail, or separately listed on a pin. Me being the laymen think, well logically I should add these up? Which apparently isn't/is the case, yet as we can see in the Avedis example clearly says 75mA per rail and has been said in this forum to draw 150mA. So in one respect it's correct to look at the 150 number but then others chime in and say no you need to look at the per rail number and then see what the power supply can handle per rail.

Geoff_T http://www.gearslutz.com/board/1914199-post147.html

Avedis
http://www.gearslutz.com/board/1914690-post151.html

Avedis
http://www.gearslutz.com/board/1719564-post13.html

All this talk about amps and milli-amps this and that, you are ALL forgetting to specify your amp rating with your reference.

Power supply specifications are usually given in reference to its Common.

So if a power supply is 1.5A, it means it is 1.5A for +16VDC and 1.5A for -16VDC in reference to its Common in the middle; or you can say it is 3A TOTAL.

Similarly, if a modules draws 40mA, you must specify if it is PER RAIL in reference to Common (which is usually is) or if it's TOTAL from both rails. Do some homework, be more specific and we can all understand each other and avoid costly confusion.

Avedis

If we look at the Purple biz. It lists 80 on the -16 and 80 on the +80. To me this 'sounds' like 80 per rail, so I think it must draw 160mA in total, but unfortunately it doesn't say that anywhere.

But if we look at the Purple Action. It lists 90 on the -16 and 90 on the +16, but also goes ahead and lists 90 as the total current consumption...

Avedis Audio MA5

MA5 Specifications
Frequency Response
    
<10Hz to -3dB at 67kHz
Input Impedance
≅1200 ohms
Output Source Impedance
<75 ohms, bias variable
Common Mode Rejection Ratio
>100dB min @ 60Hz
Total Harmonic Distortion
Cannot be explained with numbers. Graphs can help, coming soon.
Maximum Output Level
+32.2 dBu @ 100KΩ, +27 dBu @ 600Ω bias variable
Power Requirements
    
±16 vdc @ 75mA per rail

Gain Voltage
0 to 33.4 Volts
Gain dB
0 to 71.2 dB
Deviation from Linear Phase @ 40dB
Recalculating.... dg @ 20Hz, dg @ 1kHz, dg @ 20kHz
Equivalent Input Noise
-110 dBu; Unweighted 300kHz bandwidth
Weight    
2.5 lbs / 1.13kg

Biz Mic Preamp / Purple Audio, LLC

Biz Pinout

    * Pin 1: Chassis Ground
    * Pin 2: Output A +
    * Pin 3: Output B + (Purple Audio Rack Only - XLR OUT 2)
    * Pin 4: Output A -
    * Pin 5: Audio Ground
    * Pin 6: Output B - (Purple Audio Rack Only - XLR OUT 2)
    * Pin 7: Input -
    * Pin 8: Input -
    * Pin 9: Input +
    * Pin 10: Input +
    * Pin 11: Audio Ground
    * Pin 12: +15 or 16VDC 80ma
    * Pin 13: Audio Ground
    * Pin 14: -15 or 16VDC 80ma
    * Pin 15: +48VDC

Action FET Compressor / Purple Audio, LLC

Specs:

    * Total Gain: 45dBu
    * Ratios: 4:1, 8:1, 12:1, 20:1, ∞:1 ("All buttons in")
    * Attack time: Continuously Variable from over 800 microseconds to 20 microseconds
    * Release time: Continuously Variable from over 1.1 seconds to 50 milliseconds
    * Input impedance: 600 ohms
    * Output impedance: 600 ohms
    * Current consumption: 90ma 

Action Pinout

    * Pin 1: Chassis Ground
    * Pin 2: Output A +
    * Pin 3: Link In - (Purple Audio Rack Only - XLR OUT 2)
    * Pin 4: Output A -
    * Pin 5: Audio Ground
    * Pin 6: Link Out - (Purple Audio Rack Only - XLR OUT 2)
    * Pin 7: Input -
    * Pin 8: Input -
    * Pin 9: Input +
    * Pin 10: Input +
    * Pin 11: Audio Ground
    * Pin 12: +15 or 16VDC 90ma
    * Pin 13: Audio Ground
    * Pin 14: -15 or 16VDC 90ma
    * Pin 15: NC (+48VDC)

Anyway, I hope that helps explain where I have fallen off the beaten path.

[mds]

While we're at it...how much does the Averil 6 space PSU supply?

[Tim Farrant]

Well it is confusing, yes. I think manufacturers should just state the overall consumption as one figure, and in reality, it should be stated in Watts, not current.

Lets look at the Lunchbox, it's output is +/-16V at 800mA, or 32V (total) at 0.8A. Power equals the current (in amps) times the voltage (in volts), so in this case the power capacity is 25.6 Watts.

Our Elixir pre draws 150mA or 0.15 amps, which equals 4.8 Watts. This method would be far clearer for non electrical engineer types. In the case of the Biz, I would assume that the 80mA flowing into the +rail is the same 80mA flowing out of the negative rail, so it's draw is still 80mA.

If you see a spec where these 2 currents are different, you can assume there is some ground current flowing too. For example +rail 100mA and -rail 50mA, one would assume there is 50mA of ground current flowing as well (which by the way is NOT a good idea in this format due to the shared ground buss in the racks).

[Brent]

Originally Posted by mds

While we're at it...how much does the Averil 6 space PSU supply?

I couldn't find that info readily. It would be nice to know though.

Originally Posted by Tim Farrant

Well it is confusing, yes. I think manufacturers should just state the overall consumption as one figure, and in reality, it should be stated in Watts, not current.

Lets look at the Lunchbox, it's output is +/-16V at 800mA, or 32V (total) at 0.8A. Power equals the current (in amps) times the voltage (in volts), so in this case the power capacity is 25.6 Watts.

Our Elixir pre draws 150mA or 0.15 amps, which equals 4.8 Watts. This method would be far clearer for non electrical engineer types. In the case of the Biz, I would assume that the 80mA flowing into the +rail is the same 80mA flowing out of the negative rail, so it's draw is still 80mA.

If you see a spec where these 2 currents are different, you can assume there is some ground current flowing too. For example +rail 100mA and -rail 50mA, one would assume there is 50mA of ground current flowing as well (which by the way is NOT a good idea in this format due to the shared ground buss in the racks).

Again Tim. Thanks for the input on this. I guess push come to shove, an email to the manufacture is going to make a lot of sense if they don't outright say the figure like you have.

[pan60]

Originally Posted by Brent

Are you referring to space concerns ( you slut) or power concerns? The reason the lunch box has my eye, is the buy 4 components get the rack free promo that vintage king has going.

space

but let me add
i would not be to woried about the power.
notice here post 84, Rob King has four MONO GAMAs in a lunchbox.
i like to see the manufacturer give the current rating in the + and the -, only because if it is given as a total, then someone ( the world is deceitful ), will come in and say their pre ( or comp or what ever ), only uses 75 mA of current when in fact it maybe 150mA?
just my thoughts.

Originally Posted by Brent

( you slut)

yep

Originally Posted by Brent

( you slut)

yep

Originally Posted by Brent

( you slut)

yep

Originally Posted by Brent

( you slut)

yep

[Brent]

Originally Posted by pan60

space


yep

yep

yep

yep

LOL phew! For a second there I thought I was going to be forever signatured.

[Tim Farrant]

Pan60, you did not understand my posts. If the spec is given as +rail, -rail, then it just confuses people, should they add it up or not? Can't we all just say how many friggin watts it consumes like we rate main powered equipment? Would make more sense to me.

[pan60]

Originally Posted by Tim Farrant

Pan60, you did not understand my posts. If the spec is given as +rail, -rail, then it just confuses people, should they add it up or not? Can't we all just say how many friggin watts it consumes like we rate main powered equipment? Would make more sense to me.

no i did not miss understand, i am saying that their will always be some, that state this, and not that, for example is a 100 watts a 100 watts, or is it 200, or maybe 50.
when giving ratings i want all the information i can get.
if their is a loop hole large enough for deception, it will be taken advantige of by someone.
i do not see that as the case but i am just stating this as i see it.
if i look at a 100 watt amp i expect a 100 watts at 8 ohms not a 100 at 2.
the API VPR Alliance guidlines allow for a MAXIMUM POWER CONSUMPTION PER UNIT of
+16 VDC @ 60mA
- 16 VDC @ 60mA
and
48VDC @ 5mA
i just think as they have set the standard then the given specks should follow in the same fashion as well.
i would also like to see the given guidelines adhered to for this standard.
and that is not to say i have anything against a power hungry unit, but, it should be spelled out to the consumer, if a unit is not following the given specs.

[Brent]

Just as a follow up. I asked about the limits per rail on the lunchbox in a question I posed about sticking 6 MA5's in one. This was the response from API.

Hi Brent,

The only 6B’s on the market now have the new style power supplies. You shouldn’t have any problems there. As for your second question, the unit puts out 800mA per rail.

Thanks,


Ray Blevins
API Service Manager
(p) 1.301.776.7879 ext 252
(e) service AT apiaudio DOT com

API
8301 Patuxent Range Rd
Jessup, MD 20794
API Audio Products


Please note: For all international RA's, contact a customs broker and have your unit(s) shipped "Temporary Export For Repair" This will help your repair move more quickly through customs and save you in importation fees.

--------------------------------------------------------------------------------

From: Brent
Sent: Sunday, March 16, 2008 2:31 PM
To: service AT apiaudio DOT com
Subject: 500-6b and the VPR alliance



Hello,

I'm trying to clarify something regarding your 500-6b lunch box that I'm looking to purchase.

1) My understanding was the design was changed from 350mA to 800mA for the VPR alliance. Can you tell me if this is true, and if so, how do I confirm the lunchbox I'm going to purchase is the 800mA version?

2) Where do I find the current per rail specs etc. I want to add 6 Avedis MA5's to a lunchbox, but even though they are part of the VPR alliance, the current draw specs per rail have me concerned that the lunch box can handle it.

All the best,

Brent