Review: CharterOak Acoustics SP-1 (GMP 450 Pro)

For those who don't know, the CharterOak headphones are the same as the MB Quart/German Maestro GMP 450 Pro, made in Germany, then rebranded in the United States. There hasn't been much talk about these cans on the board, so I thought I'd put together my thoughts, especially given how much I like these things. I'm pretty sure anything I say here can also be applied to the 450.

Packaging, Build Quality, Comfort:
The first thing I noticed when I opened up the box these came in was the absolutely gorgeous piano-black box that these arrive in. The box is quite silly, I suppose, but I don't think the pictures I took really capture how beautiful the box is. Pretty classy stuff.



The second thing I noticed as I pulled the headphones out is how incredibly light they are. They probably weight about the same as my Beyer 990 Pros, but they feel a lot lighter, especially once on the head. They are mostly plastic, so these aren't among the indestructible German Maestro phones, but I think they will last well as long as they are respected. The drivers are suspended from the frame by a series of elastics, which make these easily the most comfortable headphones I have ever worn in my life. They stay on well with almost no clamping force, and with almost no pressure from the headband. My Beyers feel downright uncomfortable after these, and that's really saying something.

I should also mention the cord here as well. It is a straight cable, but it does have a coiled section near where the cable splits off to the earpads. If the cable ever gets tugged, the coiled section takes the strain, which means they never tug the way my Grados do. This is a great system, and avoids the major pitfalls of both straight and coiled cables. The cable itself is quite thin, and tends to tangle badly, especially given it's impressive length.



Sound Quality
As of right now, these have probably burned in about 25 hours, which I think is long enough to get the drivers moving well. I would not consider myself an expert or an audiophile, but I am serious about music and I think I have pretty decent ears. I am listening to them mostly in the following configuration:

Foobar2k Bit-perfect->USB->Fubar IV SE



Overall First Impressions:
These are really, really nimble headphones. These are closed headphones, but I wouldn't have thought so if I didn't know that. Overall, they are balanced, fast, and neutral. They can get slightly bright or clinical, but I also find them very musical with most genres.

Bass:
All of the other headphones I own are fairly bass-heavy, which made for a distinct adjustment period when I first started listening to the CharterOaks. That's not to say there isn't any bass, because these actually go quite deep, but I think that they are extremely balanced, which means they don't have that artificial bass hump that we get used to hearing. Still, bassheads need not apply.

Mids:
These have the sweetest vocal range I have ever heard. I listen to a lot of vocal-heavy rock (Jeff Buckley, Fiona Apple, Damien Rice). These sound fantastic. They come through with a perfect blend of precision and intimacy, unlike anything I have heard before. I probably should be able to compare them with some AKGs, but I don't really feel any special urge to get any now that I'm listening to my CharterOaks.

Highs:
The treble on these cans is slightly less than my Beyer 990 Pros, which is to say that they are pretty bright without being sibilant. There are certainly some moments on songs where they get a bit harsh, but it's always on tracks that show recording/mastering issues on my other headphones as well.



Soundstage:
Because of the clarity and detail, these cans also have a shockingly wide soundstage. I tried them last night with some movies and gaming, and I think they're actually my favourites now for this as well. They don't have the punch that my Beyers do, but they have a tremendously wide soundstage for closed headphones, and the airy sound and midrange really helps bring dialogue and other details out. They don't isolate as well as my Shures, but they don't leak too much sound.



I know that pads are supposed to make a big difference with these headphones. I have a pair of Beyerdynamic DT770 pads on the way (thanks Tiemen!), and I'm hoping that will bring out a bit more bass without spoiling the sweet sound through the rest of the range. I have a lot more listening to do on these cans, but I can already tell that they are the best pair of headphones that I own. I am going to include some additional impressions for songs in a separate post, which I'll use to try to explain the overall sound better. I'll post more thoughts as I spend some more time on these, especially with the new earpads.

Still, the German Maestros/CharterOak headphones are definitely worth considering for people who want to find a musical, balanced, engaging pair of headphones that can be worn for hours and work with a wide range of applications. I don't know why there isn't more talk about these cans at Head-fi.

[size=medium]Song: Jeff Buckley: Lilac Wine[/size]

CharterOak SP-1
This is where these headphones really shine. Buckley's vocals are not only crystal clear, but they sound detailed and intimate. This is one song where you really can hear the room he was singing in, but the CharterOaks really emphasize that dimensionality. The soundstage also helps separate the drums and guitar in a way I've rarely noticed before. No hint of sibillance here, though the cymbal work might be a bit bright for some. The bass is there, but it is light--exactly how it should be with this track. This is fantastic sound.

Beyerdynamic DT990 Pro
After spending some time with the SP-1, the U shaped response curve of the Beyers is more apparant than ever. While they are still a great sounding pair of cans, their shortcomings are pretty evident on this track. The bass and cymbals threaten to drown out Buckley's voice at time, while it should be the central focus throughout the track. It is a bit bright, which makes the vocal work sound unnaturally thin. Complaints aside, I still absolutely love the bass response, which is thick and rich without ever losing control.

Shure SRH 840
The Shures do a really beautiful job with this song, though a completely different presentation than the CharterOaks. Instead of the bright detail, here, it's all warmth and comfort. The vocals sound beautiful, and are nicely mixed with the other instruments. These definitely aren't bass light, but the bass never fully overpowers the rest. I still think that it's more bass than the song needs, and it does get in the way of the overall balance. There isn't as much separation with these phones, but the results are still intensely satisfying.

Grado 125i
The Grados are by far the cheapest headphones in this group, and they definitely show a lack of refinement on my go-to reference track. They handle the vocals better than the Beyers, but that Grado brightness makes the overall sound significantly less refined than on the other phones. The bass is there, but it doesn't go as deep as any of the other cans in my collection. The lack of soundstage also causes some trouble here, as all of the sound gets squeezed into the centre compared to the others. Man, Grado does have nice forward vocals, though. Not quite as refined as some others, but it's right there.

Winner: CharterOak SP-1


[size=medium]Song: Rage Against the Machine: Take the Power Back[/size]

CharterOak SP-1
This is not really the music these phones were made for, and not the kind of device RATM was thinking about when this song was mixed. Here, the lack of a bottom end is a bit of a problem. The CharterOak is content to hit those low notes, but it doesn't have much impact (though the bass slap at the top end is pretty sweet). At the same time, the nimble response time really does keep the song punchy and engaging throughout. It does a stunning job with the vocals, which never get overwhelmed despite all the other things going on. The guitar work is sharp and clean, and the separation is flawless as well. The CharterOaks are still really engaging, but it lacks that gut punch that this song should have.

Beyerdynamic DT990 Pro
There's some awesome synergy between this track and the Beyer 990 pros. They aren't as nimble as the CharterOaks, but make up for it with bass that kicks just the right amount of butt. Here, I don't mind that the vocals are recessed, but I do miss the sharp cuts of the guitar tones. The electronic sounds in the upper range is a bit obnoxious as well, but the brightness does help Take the Power Back feel even more aggressive than it is naturally. With analysis, it isn't an ideal presentation, but it rocks harder than this track does on any other headphone that I own.

Shure SRH 840
The bass is really strong here, but (as many people have already stated) these headphones are simply too polite for hard rock. It feels like the Shures are trying to smooth out the raw sound of RATM, which is the last thing I want to hear on this track. The guitars have none of the cutting clarity, the voice is overpowered by the bass, and the drums don't smack as nicely as any of the other cans. By the time they are turned up loud enough to get that punch, the overall sound gets really harsh. I like these cans, but they aren't great rock headphones.

Grado 125i
The Grado bass is nice and punchy, but this song has demands that the Grados just can't fully satisfy. Once the sound gets more busy, the Grados can't seem to keep up and keep everything separate. The guitar sounds better than on the Beyers, but it just doesn't rock as hard. The upper range roll-off helps keep the drums from dominating, but they also block that awesome snare smack that I heard with the CharterOaks. Of all the headphones, I find these the most fatiguing as well. I turned it down twice midway through the song (turned it up with most of the others). I know why people love Grados for rock, but I'm learning that I like them more for acoustic rock.

Winner: Beyerdynamic 990 Pro

[size=medium]Song: Massive Attack: Teardrop[/size]

CharterOak SP-1
Once again, the bass is there, even the really deep hits, but bassheads won't be happy with the volume. This is a track that's often used to test soundstage, and for good reason. If I didn't know better, I would say that these are open cans, and I think it's due to a really coherent and surprisingly wide soundstage. Not quite as wide as some headphones, but the separation is so clear here that it's almost distracting. This is the first track that does get a tad bright, and those who dislike treble might find them a little grating. Still, it does a great job with the female vocals as well, easily holding their own with the bass and drums. As a side note, this is definitely the headphones that do the best job with piano.

Beyerdynamic DT990 Pro
There is, as expected, plenty of bass pouring out of the Beyers on this track, but this is where the Beyers start to lose a bit of control at the bottom end. It feels a bit flabbier than it does on the other headphones in my collection, and it overwhelms both the vocals and the other instruments. It actually makes it a bit harder to track the movement of the guitar note across the soundstage, and the Beyers surprisingly seem to have a bit more narrow a soundstage than the CharterOaks, which I didn't expect since they are open cans. Imaging is not nearly as strong as I'd like, and it's clear that the Beyers aren't at their best on electronic music.

Shure SRH 840
While the bass of the Beyers is the best for hard rock, the Shures are the only headphones I have that get the right sound with Massive Attack. Here, the bass is just right, diving deep without losing any clarity. The other instrumentation gets a bit bowled over, however, and the soundstage has nothing on the CharterOaks. There's a slight harshness in the vocal range, and while it's clear, it doesn't sound as good as the SP-1 or the Grados. Still, there's this great, deep energy on this track that goes really nicely with the Shure sound. With these headphones, I have to really struggle to even hear the piano that came through so nicely on the SP-1. With a bit more clarity, these would be the clear winners for this track.

Grado 125i
As expected, the Grados just don't go deep enough for electronica. Instead, they emphasize the digital static, which is not at all ideal on this track. The soundstage is pretty claustrophobic, though it does some pretty spectacular things with the female vocal track. It pops out nicely without any hint of sibilance. The bottom end just winds up getting boomy, though, and not in the range that it should. These are the wrong headphones for this music.

Winner: Tie (SP-1/SRH-840)

[size=medium]Song: Spoon: My Mathematical Mind[/size]

CharterOak SP-1
The dominant instrument here is the piano, and the CharterOak really captures the sound of the piano, never allowing it to be overwhelmed by the other instruments. The drums sound excellent as well, featuring a surprisingly crisp and satisfying smack each time. As with the other songs, the bass could have a bit more impact, and the overall sound of the song can be a bit overwhelming with this much detail and clarity. There are a lot of instrumental layers on this track, and each one stands on its own. That, I think, is both a good thing and a bad thing. Overall, though, the CharterOak makes this track sound a bit more clinical than I am used to.

Beyerdynamic DT990 Pro
Here, it becomes much harder to follow the piano line once the rest of the instruments kick in, especially the bass line, which really rumbles on the Beyers. The track definitely doesn't sound as clean as on the CharterOaks, but these still prove to be exceptional cans for straight rock. The drums and vocals are a bit less prominent, but it gives the guitar a great raw sound, and as the song descends into musical chaos at the end, there's a ton of energy here, and it never sounds clinical for a second. The sacrifice is a lot less detail and a massive loss of imaging.

Shure SRH 840
Once again, the Shure's sound awfully pretty, but that's not what I want to hear when I listen to Spoon. The bass is a bit overwhelming for this track, and the drums don't pop as much as with the Grados or CharterOak. The vocals get a bit recessed, and the chaotic end section feels spacially compressed on the Shures. This is not the ideal track for these headphones, though there are some impressive moments of clear, clean details.

Grado 125i
The Grados like this song a lot more than the last two. Nice kick drum pop as well as the guitar, which now dominates the piano throughout the track. Despite the lack of refinement, these remain the most engaging headphones I own for this type of music. Again, I find the sound a lot more fatiguing than any of the others, but it's also completely impossible to ignore. And, until I get sick of them, I find I have a big smile on my face listening to bands like Spoon on them. Unfortunately, they had a difficult time keeping up with the chaos at the end of the track and everything just blurred together. I think this is the primary difference between $100 range headphones and $200 range headphones. They both sound great in ideal conditions, but the cheaper ones really crap out when stuff gets rough.

Winner: Beyerdynamic DT990 Pro


[size=medium]Song: Miles Davis: So What[/size]

CharterOak SP-1
The wide open soundstage really sounds great on this track. This is definitely a front-row pair of headphones, to the point that the instruments almost feel too spread apart. That minor complaint aside, the speed and neutrality of the SP-1 makes it really awesome for jazz. I used to play in some jazz bands, and the sound of each instrument is spot on with these headphones. The bass is extended enough to capture the double bass, but it's not artificially boosted. Also, the CharterOak captures the overall resonance of the room really nicely. It feels like a live performance, not like a studio recording.

Beyerdynamic DT990 Pro
The Beyers aren't meant for jazz. The bass has nice resonance here, as do the sound of the cymbals, but that's the best part here. The trumpet is sometimes in that sweet upper range of the phones, but it doesn't sound as clean or natural as on the CharterOaks. If the CharterOaks are front row, these would be one or two rows back, but now the acoustics of the room don't sound as natural or clean. The biggest problem is that it just isn't as engaging. It's easy to ignore the track here and it just sinks into the background. They don't sound terrible, but they definitely don't sound as good.

Shure SRH 840
These sound a lot farther back than any of the other headphones. They give the double bass a really nice deep resonance, but it doesn't sound as natural or clean as some of the other cans. The roll-off at the top prevents the drums from dominating, but it also takes off any sparkle that cymbals usually have. The trumpet and sax sound a lot more relaxed, but I prefer the energy, brightness and clarity of the CharterOaks. These are decent headphones for jazz music, though, especially for people who dislike brighter sounding headphones. Quite a bit of that presence gets lost in the attempt to smooth things out, though, and it doesn't sound as "live".

Grado 125i
I was a bit worried about the Grados with this track, but they actually sound pretty good. The smaller soundstage makes the song a bit more intimate, and the Grados do great things with the trumpet and sax. What gets lost is the sense of presence in the room. That incredible sense of space on the better cans just gets lost, replaced by a vague sense of depth and echo. As well, the volume of the bass really fluctuates with the range. Still, these would be decent budget headphones for jazz--better than anticipated.

Winner: CharterOak SP-1

Thanks for reading!

Amazing review... you also have nice taste in music. How well do these isolate?

Not at all if they are indead identical to the German Maestro 450 Pros... Which they surely seem going by the pictures and the review. Why the rebranding is the company sold again? They really get to little space here on head fi that is for sure. Need to release a statement headphone I suppose. All business probably don´t work to well over here

I agree 100 % on the vocals... these are the only headphones I have ever heard that match my KeeS modded Pro 900 in that area. I loved watching movies with them for that reason. Even though soundstage on the German Maestros is very stereo. More wide then deep.

I made the misstake and go for the 435S. Since the 450 Pro didn´t isolate that well I thought I should go with the fully open version. But the 450 Pro have this juicy mid range which is amazing for classical apart from tv series.

As for replacement pads you could just mail german maestro for replacement. But stock pads are the "bassiest version" you will get.

Yeah, surprisingly little isolation for closed headphones. I find the sound doesn't bleed out TOO bad, but it doesn't block out much outside noise either. Still, it's better at that than my Grados (I swear those things are louder for people nearby).

ok, these sound a lot the akg 271... can anyone compare?

Acix said that they have a similar sound signature, but they probably isolate quite a bit better.

Quote:



I had the GMP250 and the K271.
For sound I preferred the GMP250, because of a more upbeat sound (more PRaT), and louder/deeper bass.
For isolation I preferred the K271, they isolate a lot better.

BTW: great review. I'm curious how the Beyer pads will affect the sound....

Tiemen have you ever heard the 450 Pro? May want to sell my 435S and get either the 450 or 250.

Quote:



No, I didn't hear the 450....

Do they isolate enough to be used in a room with other persons? I need a pair of closed cans so I can listen to music in the livingroom, while my wife is working.

It depends how loud you listen. If you listen at moderate levels, there is some leakage (less than open headphones but not great). If you like blasting your tunes, your wife won't be happy.

So, better than a k7xx, not as good as a 271.

Quote:



OK thx I will look for some other cans, but please report if the beyer pads will improve the isolation, on my list is ATM Shure 840 and Kenwood K1000 I don't think I will buy the K271 as I allready have the K400s and I suspect they have a similar soundsignature.

nice review, looks like these cans come with a lifetime warranty as well which is a major plus

@joelpearce, how much is this handsome phones?