single vs dual channele pre-amps?

[dnf777]

Hi All,
Probably more academic than practical concern here, but is there any advantage to using a dual channel preamp when recording with say stereo 84s, over just two single channel amps? In my rack, I have two Presonus channel strips (one for each mic) but saw a good deal on a used WA273.

I'll noodle around and figure something out, but wondered if any of the seasoned sound guys have any advice or tips on one or the other?

TIA,
Dave

[KevWind]

Originally Posted by dnf777

Hi All,
Probably more academic than practical concern here, but is there any advantage to using a dual channel preamp when recording with say stereo 84s, over just two single channel amps? In my rack, I have two Presonus channel strips (one for each mic) but saw a good deal on a used WA273.

I'll noodle around and figure something out, but wondered if any of the seasoned sound guys have any advice or tips on one or the other?

TIA,
Dave

Humm I would assume all else being equal, the only advantage of, 1 two channel pre --- over 2 one channel pre's of the same brand ,,, is logistical ..
i.e. One unit, one power chord, one set of mounting screws, etc.

Now switching to a different brand of pre is an entirely different ball game

[Glennwillow]

Hi Dave,

I have a Warm Audio WA273, in fact, two of them for 4 channels, total, and I like them. I have seen no disadvantage in using stereo units.

- Glenn

[dnf777]

Originally Posted by KevWind

Humm I would assume all else being equal, the only advantage of, 1 two channel pre --- over 2 one channel pre's of the same brand ,,, is logistical ..
i.e. One unit, one power chord, one set of mounting screws, etc.

Now switching to a different brand of pre is an entirely different ball game

that was kind of thought as well. as for different brands, I do have a few others that i occasionally run in the mix. as has been discussed here before, Other than phase cancelling, I don't mind different sounds, brands, mics, etc...I feel that if you matched everything as close to perfect as possible, you eliminate the entire purpose of stereo recording. I remember one of the recording sages here (I think) pointing out in regards to matched mic sets, that our ears are not matched, so why should the mics be?? haha.

But yes, I certainly see the immediate advantage of saving on 4 rack screws and a IEC cord. (and space on my power strip)

Having fun playing around....just wanted to see what the cool kids are doing.

[KevWind]

Originally Posted by dnf777

that was kind of thought as well. as for different brands, I do have a few others that i occasionally run in the mix. as has been discussed here before, Other than phase cancelling, I don't mind different sounds, brands, mics, etc...I feel that if you matched everything as close to perfect as possible, you eliminate the entire purpose of stereo recording. I remember one of the recording sages here (I think) pointing out in regards to matched mic sets, that our ears are not matched, so why should the mics be?? haha.

But yes, I certainly see the immediate advantage of saving on 4 rack screws and a IEC cord. (and space on my power strip)

Having fun playing around....just wanted to see what the cool kids are doing.

Not sure I understand the bold part
Even with a matched pair of mics into a matched 2 channel pre you are still going to get a definite stereo recording (because the mic's are two different discrete sources of sound).
Now even if you pan both tracks or both sides of a true 2 mic stereo recording to the center while you are going to loose the stereo filed effect and it will come out just in the center it will (IMO) sound different than a mono track panned to center.. Or even a duplicated mono track panned to center

[Doug Young]

I think he means if you take it to the limit where both tracks are literally identical, then that's mono. Of course thats not going to happen with 2 mics, because even if the entire signal chain was identical to the point of perfection, the mics won't occupy the same physical space, so they will pick up differently (even if you put them together side by side, there will be some difference).

That said, I don't think "stereo" created by entirely different-sounding sources is as satisfying as one produced by mic placement. An extreme case is using a mic on one channel and a pickup on the other. That produces a pretty dramatic and interesting "stereo" effect. It's just not very natural.

[dnf777]

Yes, I over-simplified and overstated the point, but thats what I was getting at. I think small differences in L and R give us a stereo effect, in addition to a sound reaching our two ears at slightly different points in time, that our brains use to localize sound points. (Bats, sperm whales, and owls all catch prey with a highly developed echo-location, which is stereophonic listening on steroids).

I guess my question is, why worry about *slight differences” in preamp tone, when those very tonal variations may contribute to a desirable effect? Im playing around with this, and seeing what works, and what doesnt.

So far, mic placement easily trumps all other variables. (Pre amps, mic matching or not, even different mic types)

[Doug Young]

Originally Posted by dnf777

So far, mic placement easily trumps all other variables. (Pre amps, mic matching or not, even different mic types)

It all depends on the degree. I think with most electronics, you'd be unlikely to notice any difference - or at least casual listeners won't. Same with unmatched but same type/brand mic, or even different brands of similar mics. But going further, you start hearing things. For example, I posted a demo a while back using a ribbon on one side, condenser on the other, and several people found the stereo image to be too "odd" in some way (and I agreed). The mic/pickup combination is even more extreme. But someone might actually want an exaggerated, unnatural sound, so it just depends.

[jim1960]

As pointed out, there have to be some differences between the left and right tracks to achieve stereo. The mic positioning alone can achieve that. Using different mics through the same preamp can further the effect. Using different mics through different preamps can push it even further. But somewhere along that journey you risk diminishing returns where the stereo image sounds unnatural and becomes a distraction.

I've done enough recordings where I've used an LDC and SDC going through the same preamp to know I can make that work for me. In post, I usually try to bring the tracks closer to each other in sound so the image isn't bright on one side and boomy on the other. I'm not trying to make the sound identical, just trying to lessen the disparity a bit so the image doesn't strike me as lopsided. I don't think I'd ever have a need or desire to make the initial tracks more disparate than what I'd get with the LDC/SDC combo.

If I'm using the same mic for both tracks, it's because I want the kind of subtle stereo image using identical mics provides. I can't think of a case where I'd want to use different preamps on the left and right tracks.

[j3ffr0]

Originally Posted by dnf777

So far, mic placement easily trumps all other variables. (Pre amps, mic matching or not, even different mic types)

similar to my experience. Although you can certainly get some more drastic (and likely less desirable) differences with radically different mics and preamps.... Say a SM58 paired with a KM184. Or a clean solid state pre paired with a tube pre pushed to saturation. Also a placement that works for one mic might not well for another.... they can have different sweet spots/good working distances.

[dnf777]

Thanks. Lots of good info to work with. Doug, I somehow missed the vid you mention. I will find and watch it. They are always a learning experience, and much appreciated.

If i stumble across a set up that produces results, and have enough Woodford Reserve, I’ll maybe post….

[DupleMeter]

Originally Posted by dnf777

Hi All,
Probably more academic than practical concern here, but is there any advantage to using a dual channel preamp when recording with say stereo 84s, over just two single channel amps? In my rack, I have two Presonus channel strips (one for each mic) but saw a good deal on a used WA273.

I'll noodle around and figure something out, but wondered if any of the seasoned sound guys have any advice or tips on one or the other?

TIA,
Dave

It’s a classic “six of one, half dozen of the other” scenario. In both cases you have the same thing. The difference being having 2 fully separate preamps vs 2 separate preamps in a single housing sharing a power supply.

I wouldn’t worry about it.