Topic: PT: 2 - New Marantz PMD661

[datbrad]

Line in on the 661 is set at +4db pro line level, so the old tradition of setting a recorder to line in to allow more headroom (what I expect you are contemplating) would not work well with the 661, even if you could run it like that. When taking a normal pro level line in, the 661 gain knob sits between 12 and 2, which shows how much headroom you have and how much gain you need to use.

Good luck with your quest.......

I guess I need to read up, but can you explain what the deal is with the '+4dB pro line level?'  I searched and googled it but didn't find anything relevant.  Are you saying going line in with a +4dB pro line-in wouldn't be a great idea because the levels would be too low compared to a consumer line level?  Thanks for the info!

Edit: found this old DAT Heads newsletter from an old post here (thanks greenone!) that seems rather informative:

In that old datheads post you pasted, I saw where +4db line level overloading -10db line level inputs is mentioned.

"The problem mainly occurs when a deck with consumer level line inputs of
-10dBV is hooked up to a pro console that had +4dBu line level outs."

Consumer line level, such as the line level between your CD player and home receiver, is set at -10db, and all consumer grade components are made to feed and accept line level at -10db, so when a recorder with a unbalanced consumer level line input is fed the +4db pro line level, which is 14db hotter, it can often overload the active electronics on the recorders line input.

In fact, other than the Sound Devices 702/722, I am not aware of any other 2 channel flash/HDD wave recorder that has a +4db pro line in with balanced XLR input connectors, other than the 661. I have used the 661 for SBD patches taking the balanced XLR outs, and had just tons of headroom that I would not have had with unbalanced consumer level line inputs.

[su6oxone]

In that old datheads post you pasted, I saw where +4db line level overloading -10db line level inputs is mentioned.

"The problem mainly occurs when a deck with consumer level line inputs of
-10dBV is hooked up to a pro console that had +4dBu line level outs."

Consumer line level, such as the line level between your CD player and home receiver, is set at -10db, and all consumer grade components are made to feed and accept line level at -10db, so when a recorder with a unbalanced consumer level line input is fed the +4db pro line level, which is 14db hotter, it can often overload the active electronics on the recorders line input.

In fact, other than the Sound Devices 702/722, I am not aware of any other 2 channel flash/HDD wave recorder that has a +4db pro line in with balanced XLR input connectors, other than the 661. I have used the 661 for SBD patches taking the balanced XLR outs, and had just tons of headroom that I would not have had with unbalanced consumer level line inputs.

Thanks for the clarification/info!  It seems that having a pro +4dB line level is useful for SBD patches to the 661, essentially, since those levels can overload a prosumer/consumer -10dB level XLR line in.  However, since the 661 doesn't have phantom for the line level, this doesn't apply to high SPL sound sources like rock concerts I would assume, at least when running mics directly into the 661.  If the 661 could supply phantom for the line in as well as mic in (like the 7xx), this problem with overloading (albeit, with certain mics in rare situations it appears) might not be an issue at all.  Despite that, the 661 seems like a mighty fine recorder. 

[datbrad]

In that old datheads post you pasted, I saw where +4db line level overloading -10db line level inputs is mentioned.

"The problem mainly occurs when a deck with consumer level line inputs of
-10dBV is hooked up to a pro console that had +4dBu line level outs."

Consumer line level, such as the line level between your CD player and home receiver, is set at -10db, and all consumer grade components are made to feed and accept line level at -10db, so when a recorder with a unbalanced consumer level line input is fed the +4db pro line level, which is 14db hotter, it can often overload the active electronics on the recorders line input.

In fact, other than the Sound Devices 702/722, I am not aware of any other 2 channel flash/HDD wave recorder that has a +4db pro line in with balanced XLR input connectors, other than the 661. I have used the 661 for SBD patches taking the balanced XLR outs, and had just tons of headroom that I would not have had with unbalanced consumer level line inputs.

Thanks for the clarification/info!  It seems that having a pro +4dB line level is useful for SBD patches to the 661, essentially, since those levels can overload a prosumer/consumer -10dB level XLR line in.  However, since the 661 doesn't have phantom for the line level, this doesn't apply to high SPL sound sources like rock concerts I would assume, at least when running mics directly into the 661.  If the 661 could supply phantom for the line in as well as mic in (like the 7xx), this problem with overloading (albeit, with certain mics in rare situations it appears) might not be an issue at all.  Despite that, the 661 seems like a mighty fine recorder. 

The Oade modded 661, concert  or warm, can take plenty of input gain XLR mic in, with three optional attenuation positions for the input, -6, -12, and -18 db. If you were to run a pair of commonly used mics that are known to output hot, like AKG 480s, and ran them mic in with the setting at -18, you would have more than enough headroom to work with, even for bands that are very loud.

I personally run outboard pre still with my 661, for several reasons, but mostly because the battery life on the 661 is vastly increased when you run XLR line in, versus XLR mic in with 48V phantom. I cannot hear any significant difference in the sound between going mic in directly, versus line in from the mic pre, which I suspect is due to the fact that the Oade mod upgrades the analog path for the XLRs, line or mic in. This means, unlike most modded recorders, the sonic improvements of the mod are in play with line in, as opposed to only acting on the mic input side.

Again, good luck with whatever you end up doing.

Edit to correct spelling

[su6oxone]

The Oade modded 661, concert  or warm, can take plenty of input gain XLR mic in, with three optional attenuation positions for the input, -6, -12, and -18 db. If you were to run a pair of commonly used mics that are known to output hot, like AKG 480s, and ran them mic in with the setting at -18, you would have more than enough headroom to work with, even for bands that are very loud.

Thanks again for all the info, sounds like a recorder I may end up getting eventually.

[eman]

You will not find too many recorders, if any, that have phantom power on the line inputs. Just imagine the potential destruction if you fed 48V to the line out on a SBD (crispy  ).

Now, with so many new recorders out, some SBD guys are very wary of patches these days, because someone might accidently feed 48V phantom and fry part of the mixing desk.

Would it be possible to add a diode to your xlr sbd patch cable to prevent this from happening?

[datbrad]

You will not find too many recorders, if any, that have phantom power on the line inputs. Just imagine the potential destruction if you fed 48V to the line out on a SBD (crispy  ).

Now, with so many new recorders out, some SBD guys are very wary of patches these days, because someone might accidently feed 48V phantom and fry part of the mixing desk.

Would it be possible to add a diode to your xlr sbd patch cable to prevent this from happening?

I am not sure about that, but what I do know is if a FOH guy is wary that you might even possibly be able to accidently feed phantom back to the mixing desk, no claims of any preventative modifications will reassure most of them that they can take a risk and will not have to explain to the band later why they have to get their SBD repaired, or have to pay a venue to have their's repaired.

There is no application I can think of that would call for a line level input to have the ability to feed phantom. Someone seeking to be able to run their mics line in need to have a preamp in front, or at least a phantom power box, then they can go line in with the mics easily. But, with the 661, if you fed only mic level to the XLR pro line input, I doubt you could get full levels even with the gain cranked all the way up from such weak source going into the +4db XLR line in on the 661. Trust the modded 661 preamps with the -18 attenuation setting, or get a preamp and go line in, that is my advice.

[datbrad]

Doug Oade recently updated his site, with the following on the 661 upgrades. Good explanations of differences for those seeking more detail.

"Performance Enhancements Available :

The Marantz PMD 661 Concert MOD upgrade rebuilds the XLR inputs using high speed, low noise and very low distortion op amps that dramatically improve fine detail and clarity. The result is a very detailed, open 3D soundstage. Input PCB capacitors are also upgraded. Components are selected by ear to optimize detail and imaging for recording all types of music where transparencey is needed.

The Marantz PMD 661 Warm MOD upgrade rebuilds the XLR inputs using high speed, low noise and very low distortion FET chips that dramatically improve fine detail and clarity. The result is a very detailed, open 3D soundstage with a warmer tone than the Concert MOD plus a more expansive soundstage. Input PCB capacitors are also upgraded. Components are selected by ear to optimize detail and imaging for recording all types of music when a warm tone is needed.

The Marantz PMD 661 Super MOD upgrade rebuilds the XLR inputs using very high speed, very low noise and super low distortion op amps that dramatically improve low level detail and clarity. Input PCB capacitors are also upgraded. Super low THD+N op amps allow for a very wide SFDR even with signal levels down 50dB. This preserves the signal quality of the highest grade microphones when recording soft signals, like voice, un amplified music, nature sounds and FX.



The preamp chips used for the Super MOD have lower THD than the stock ones (about 30db less). The Super MOD chips do a bit less hiss than the ones for the Concert and Warm MOD chips. This is preferred for very soft signals as there is less signal to mask the noise. The Concert and Warm MODs also use chips with much lower THD than the stock chips but the gain structure altered to accommodate the much higher signal levels found in a Concert setting. When high output mics are used in a high SPL concert both the stock and Super MOD machines can overload. All upgrades dramatically enhance clarity and low level detail in recorded signals by significantly lowering the distortion in the preamp. To sum up, the Concert and Warm MODs optimize the preamp circuit for clarity and detail in higher SPL settings while the Super MOD optimizes it for more common signal levels like nature sounds, voice and Acoustic music. Also, the Warm MODs preamp chips use FETs so they sound very much like a tube preamp with the warm sound that offers a fat rounded bass tone, a sweet silky high end and the expansive soundstage found in high end tube circuits. Unlike the Concert MOD which is transparent or uncolored, the Warm MOD does add euphonic coloration to the recorded signal."

[su6oxone]

Thanks for posting the more detailed description of the mods.  Anyone know if it is confirmed that the Oade modded 661s lower the noise floor? 

[datbrad]

Thanks for posting the more detailed description of the mods.  Anyone know if it is confirmed that the Oade modded 661s lower the noise floor?

I don't know if anyone has done so using measurement equipment. I can say that the stock unit has published specs showing a SNR of 65 db mic in, and 85db line in. A 16 bit stock SBM-1 has better specs than this.

Doug told me the chips he used for the super mod were rated SNR of 125 db, and the ones for the concert/warm were around 115 db.

The only show that I have recorded using the mic in on my wmod661 was an acoustic trio running DPA4061s. During the performance, the audience is pin drop quiet, and the amount of audible hiss is minimal, my own breathing masks it.

Now this is not scientific, but if the SNR had been 65 db, it would have sounded like a chorus of snakes. So, based on my experience, I would say the mods definately lower the noise floor audibly, but exactly how much I cannot say.

[su6oxone]

Thanks DATBRAD, appreciate the info.  It would be great if would add the Oade modded 661s to their tests, as well as testing the line ins. 

[datbrad]

Thanks DATBRAD, appreciate the info.  It would be great if would add the Oade modded 661s to their tests, as well as testing the line ins.

It would be nice to have such tests, but I don't expect to see that anytime soon.

Personally, I was familiar enough with Doug's work, and Marantz gear, to not need a ton of outside convincing to make the purchase decision. I just went for it. The differences between the stock 660 and his modded 660 are stark, and the 660 was basically not usable for concert PA taping until after his mod. I have also heard the clear quality differences between a stock 671 and a modded 671, as well as a stock P2 versus modded P2.

I can't imagine that the 661 mods are any different as far as impact.

I expect you are seeking a smaller and lighter alternative to your 702 for stealth, and I can say that the show I did stealth was very easy with the 661, and all I had to do was tape down the level knob, since the keylock protects the rest of the controls. If you are looking to stick with your 702 for open taping, and adding this recorder to your gear locker for low the pro stuff, this is a great option for you.


Running Schoeps, I would go with the concert or super mods, depending on if you are recording loud PA stuff, or quiet acoustic. YMMV

[su6oxone]

If you are looking to stick with your 702 for open taping, and adding this recorder to your gear locker for low the pro stuff, this is a great option for you.

Running Schoeps, I would go with the concert or super mods, depending on if you are recording loud PA stuff, or quiet acoustic. YMMV

Exactly right, I love the 702 but find it a bit bulky to stealth properly, and like the 661 a lot from what I've seen and heard and would love to have one to stealth with as well as to get board feeds with (with the pro level line-in).  It's significantly cheaper to go stock and get it on ebay with cashback, so I'll have to figure out if I want to go Oade or not.  Maybe I'll give Doug a call to see what he thinks.  Thanks for the input!

[skaggs]

I think the warm is perfect for schoeps.  doug said it would be closest to the m118 i run in front of my p2.  i have run 3-4 sets mk4/mk2s into the 661 warm with phantom, all at telluride bluegrass, nothing loud yet.  pm me if you want to check that out.  i never upload, i haven't figured it out and don't have the time while i am in school.

richard

[su6oxone]

i have run 3-4 sets mk4/mk2s into the 661 warm with phantom, all at telluride bluegrass, nothing loud yet.  pm me if you want to check that out.

PM sent. 

[su6oxone]

So I did a battery test at home with my unmodded 661:

Schoeps CCM4 > 661 (backlight on continuously at lowest setting, LED on, 24bit/44.1) using 2700mAh Sanyos.  Lasted about 4 hours before it died.  The 661 was set to "NiMH" but the battery meter was showing only half power left at the 2 hour mark, but it kept on recording for another two hours.  A bit disconcerting.

Problem is, the 661 does not seem to have written the long file prior to shutting down when the batteries died. Is this generally an issue with the 661?  Do I have to worry about turning it off before the battery power runs out or else risk having the file not properly closed/saved?