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Moondrop May (IEM with USB C DSP cable)

Jimbob54

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Just taken delivery of these.

Bottom line, lovely design and shape. Comfy though I find the cable ear hooks a bit heavy and stiff for my tastes (as with the Free DSP but YMMV) Nice case with it too.

Sound great- Standard EQ profile works best for me so far but see issues regarding the presets below.

Whoever procured the stock tips needs a talking to- the bores are far too small, almost like they were made for an entirely different nozzle. I wouldnt like to have arthritis and try to squeeze them on- works with a bit of patience.

It very much does appear this is the Free DSP cable discussed elsewhere rebadged and with a few May specific EQ settings stored. Sadly when you select a preset you cant see in the PEQ window what the adjustment filters are. More annoyingly there are big gain variances between the different presets. "Standard" is way higher than the "Reference" for example yet oddly the measurements of the same show the Reference setting as having an almost identical FR aside from a LOWER bass shelf - so surely should have had the same gain reduction as the "Standard" setting? It makes quick comparisons by switching on the app (which is still very rough and ready) impossible as the volume difference is so noticeable.

Overall I cant argue with it at all. No need for a USBC dongle, decent cable, great sound for around £60. Better value out there for sure but these feel a bit more premium than some of the c£30 offers.
 
Something I have noticed, but need to try with other phones is when I first connect the May and before I grant usb control to uapp and launch it, there is a high pitch whine coming through the iem. Not sure what would happen if I just used a player app that goes through the android mixer if the whine would remain.

As I said, will experiment with a different handset to connect to.
 
Let's hope the app gets better
Let's hope they will release a non-DSP version with a normal analog cable included (or no cable at all) for lower price. They make great IEMs, but I'd let others deal with DSP and app development.
 
Let's hope they will release a non-DSP version with a normal analog cable included (or no cable at all) for lower price. They make great IEMs, but I'd let others deal with DSP and app development.
I doubt it. Suspect they see the DSP thing as a bit of a differentiator. Looks like the B3 Dusk will take the same approach. Luckily the non DSP tuning on the May is pretty good so a swap to a regular cable is an option without needing tonnes of filters.

Looks like the main use of DSP in the cable is to adjust bass level (obviously) and fill the 6k hole. The "standard" preset seems to reduce the whole ear gain region too.
 
Let's hope they will release a non-DSP version with a normal analog cable included (or no cable at all) for lower price. They make great IEMs, but I'd let others deal with DSP and app development.

Then it would just be another cheap IEM. USB-C plug and DSP is a key differentiator, especially at this pricepoint (Gah! I sound like i'm 'in marketing', I'm not!)
 
I think they will have to give the option to opt out the dongle, at least the detachable versions. When customers start to accumulate 2 or 3 free DSP I guess many will start letting them know they don't need one more
 
Then it would just be another cheap IEM.
Well, I personally would be interested in a well-measuring and nicely shaped IEM with a planar driver around $50, just out of curiosity. But I have no use for a DSP cable with subpar software — I have my own means of EQ should I need it.
 
Still no measurements or data on the capabilities of these "DSP Cables" yet no?
 
Well, I personally would be interested in a well-measuring and nicely shaped IEM with a planar driver around $50, just out of curiosity. But I have no use for a DSP cable with subpar software — I have my own means of EQ should I need it.

I have the FreeDSP cable attached to, and EQ'd for, my Truthear x Crinacle Zero Blues. I keep them in my bag with a USB-C to A adapter as a backup pair of IEMs (primary IEMs are Zero Reds + Q5K). They FreeDSP+Blues don't need to be charged and I can plug them into phones, tablets and work PC and enjoy my EQ'd Zero's. Sure, the app is a little flaky, but it's not unusable.
 
Any THD vs. FR\level measurements available?
I wonder at what levels they measured what they posted on the product's page. I mean, they already provide the information - why not go all the way and supply the conditions in which it was measured?
Seems like the DSP does affect FR from the box, so switching the cable between different IEMs will affect their FR accordingly:
 
Any THD vs. FR\level measurements available?
I wonder at what levels they measured what they posted on the product's page. I mean, they already provide the information - why not go all the way and supply the conditions in which it was measured?
Seems like the DSP does affect FR from the box, so switching the cable between different IEMs will affect their FR accordingly:
No idea about other measurements. I believe it ships with the "standard" eq preset on. If you set all the eq filters to 0 manually it's the same FR as just using a dumb cable. So yes, swapping to the cable to a different set of iem will lower sub 200hz by a couple of dB, flatten the ear gain hump and add a c5 dB peak at 6khz.

I think the treble driver in these might be more distinguishing than the cable tbh.
 
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I think they will have to give the option to opt out the dongle, at least the detachable versions. When customers start to accumulate 2 or 3 free DSP I guess many will start letting them know they don't need one more
That's interesting... because I'm heading straight toward the exact opposite situation: I only need to accumulate two or three 3.5 / 4.4mm cables to fiddle with my Qudelix 5K & T71... But when I'm done, these USB-C DSP thingies are pretty slick! Between Tanchjim and Moondrop, I have already accumulated a dozen (!!!) of these USB-C DSP cables & IEMs (no quite: MAY is yet to be delivered).

I also wonder--a conspiration theory of mine--whether Moondrop intends to better capture their users FR preferences through the App cloud repository & "review process", so that they can better target future products.

EDIT: BTW, I am also messing with a Bugblat USB sniffer, trying to understand the commands protocol between the App and DSP--it cannot be that complicated (...???!!!). I am also willing to butcher a FreeDSP to find out what chip is used :D I just need to find some time... :rolleyes:
 
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I also wonder--a conspiration theory of mine--whether Moondrop intends to better capture their users FR preferences through the App cloud repository & "review process", so that they can better target future products.

Having seen some of the user uploaded presets I am not sure that is a good idea. I found one today that had 3 separate dips at 1khz totalling -20 dB or more.
 
Still no measurements or data on the capabilities of these "DSP Cables" yet no?
This link was reported in the FreeDSP thread:

 
No idea about other measurements. I believe it ships with the "standard" eq preset on. If you set all the eq filters to 0 manually it's the same FR as just using a dumb cable. So yes, swapping to the cable to a different set of iem will lower sub 200hz by a couple of dB, flatten the ear gain hump and add a c5 dB peak at 6khz.

I think the treble driver in these might be more distinguishing than the cable tbh.
If the “standard” preset is not all 0, wouldn’t it mean that MAY was intentionally designed to be DSP-only? In other words, Moondrop did not try to match a FR “target”—relying on the DSP standard preset instead—allowing them to focus on other parameters (distortion?) or design goals.
Moondrop did exactly that with “The Droplet” (factory-DSP’ed, no app support).
That would be a clever idea for entry-type IEMs…
 
If the “standard” preset is not all 0, wouldn’t it mean that MAY was intentionally designed to be DSP-only? In other words, Moondrop did not try to match a FR “target”—relying on the DSP standard preset instead—allowing them to focus on other parameters (distortion?) or design goals.
Moondrop did exactly that with “The Droplet” (factory-DSP’ed, no app support).
That would be a clever idea for entry-type IEMs…
Honestly cant figure out their intentions with the supplied DSP presets and how they have been implemented.

The "DSP set to zero" response seems pretty good to me. "Standard" is miles away from Harman, their own VDSF target, Crinacle and all the rest. Yet sounds good. So go figure
 
Honestly cant figure out their intentions with the supplied DSP presets and how they have been implemented.

The "DSP set to zero" response seems pretty good to me. "Standard" is miles away from Harman, their own VDSF target, Crinacle and all the rest. Yet sounds good. So go figure
Standard should be very similar to Crinacle (FR measures like TruthEar RED) and I find it better balanced than the Harman target (always found it too hot/harsh and bass heavy). BTW standard should be that far-off from the Harman target.
I am still unsure regarding the "no eq" FR. This 6kHz dip really bothers me, especially when there is a brass section.

Do you get a weird, soft beep whenever you pause/play music? For like a second or two

Mine came without any EQ from the box. Required the app to apply the "standard" profile
 
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Something I have noticed, but need to try with other phones is when I first connect the May and before I grant usb control to uapp and launch it, there is a high pitch whine coming through the iem. Not sure what would happen if I just used a player app that goes through the android mixer if the whine would remain.

As I said, will experiment with a different handset to connect to.
Did you manage to get rid of it? I have it each time I pause/play/connect the earphones.

For me reference and standard seem to be the same volume, and all the built-in EQs are much lower volume/gain than no EQ.

And the design of the tips is extremely dumb indeed.

Update: apparently the app is really bad. Many times it doesn't recognize the device and it keeps resetting the EQ to 0 (not standard. so it also increases the volume).
 
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Did you manage to get rid of it? I have it each time I pause/play/connect the earphones.

For me reference and standard seem to be the same volume, and all the built-in EQs are much lower volume/gain than no EQ.

And the design of the tips is extremely dumb indeed.

Update: apparently the app is really bad. Many times it doesn't recognize the device and it keeps resetting the EQ to 0 (not standard. so it also increases the volume).
Nope- doesnt bother me though as I always use it with UAPP and it disappears when UAPP connects to it.

Plenty of times the app doesnt recognise it though. And as I also complained about with the standalone Free DSP cable- what the app REALLY needs is an EQ on/ disabled function and to display the actual live EQ profile (it shows the last one you clicked on in blue regardless of whether you applied it or not)
 
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