[brat]

Quote:

Originally Posted by spritzer /img/forum/go_quote.gif That's the midrange "honk" I've been talking about.

I'd not determine it as a midrange problem but more of the highs. It appereared after more than 400hrs of burn-in and became audible in very short period. I just began to notice some sounds within a certain (high) frequency area, often some ticking sounds...
If it's the midrange problem you mentioned before and every O2mk2 suffers from it that's a huge fault of the stax' engineers

 

[spritzer]

Quote:

Originally Posted by brat /img/forum/go_quote.gif I'd not determine it as a midrange problem but more of the highs. It appereared after more than 400hrs of burn-in and became audible in very short period. I just began to notice some sounds within a certain (high) frequency area, often some ticking sounds... If it's the midrange problem you mentioned before and every O2mk2 suffers from it that's a huge fault of the stax' engineers

To my ears it is a midrange problem that is exacerbated by the more forward nature of the phones. It presents as a "shout" on top of male vocals and other instruments on a similar frequency band, where they are singled out and have added harshness compared to the rest of the mix. It's a subtle effect but very noticeable when comparing the phones to the Mk1 and SR-Ω.

 

[powertoold]

Would someone please comment on the technical differences between a Lambda Pro and an O2Mk1 in terms of the sound? For example, so the imaging of the O2Mk1 is better, but do you have an analogy of how much better it is? It'd be great if you could point out other technical differences too!

 

[Akabeth]

Can anyone here tell me if any/all Stax headphone amps have temperature sensors...? or at least something to prevent the amp from getting damaged due to overheating?

I think I found something (delightfully) consistent on my SRM-717

Quote:

Originally Posted by powertoold /img/forum/go_quote.gif Would someone please comment on the technical differences between a Lambda Pro and an O2Mk1 in terms of the sound? For example, so the imaging of the O2Mk1 is better, but do you have an analogy of how much better it is? It'd be great if you could point out other technical differences too!

I heard Lambda Pro/SRM1-mk2 in the Chicago meet which I enjoyed a lot. I may expand on this later but as far as first impressions go is that the Lambda Pro was noticeably brighter compared to the o2 mk1 (which I'm using right now). Sparkly highs, good-tight bass. It was great on strings (guitar). I didn't notice anything special about the imaging, coherency, sound staging, etc... So take what you will from that ^ :X

I was just enjoying myself because it was my first-ever Stax'en and listening to an e-stat headphone! I didn't bother to do anything but enjoy the music

 

[dvse]

Quote:

Originally Posted by brat /img/forum/go_quote.gif I'd not determine it as a midrange problem but more of the highs. It appereared after more than 400hrs of burn-in and became audible in very short period. I just began to notice some sounds within a certain (high) frequency area, often some ticking sounds... If it's the midrange problem you mentioned before and every O2mk2 suffers from it that's a huge fault of the stax' engineers

Your description is not very clear, but perhaps what you are talking about are ticking noises one gets when some detritus/dust gets inside the driver? Is what you hearing really on the recording (try another headphones)? Also try unplugging the SR-007 - if ticking persists, it's definitely a dust issue.

 

[dvse]

Quote:

Originally Posted by powertoold /img/forum/go_quote.gif Would someone please comment on the technical differences between a Lambda Pro and an O2Mk1 in terms of the sound? For example, so the imaging of the O2Mk1 is better, but do you have an analogy of how much better it is? It'd be great if you could point out other technical differences too!

In my experience, the most similar headphones to to the SR-Lambda Pro are the SR-202.

SR-Lambda Pro do not really have resolving deep bass, are thin in the midrange, are often sibilant, have a slightly metallic coloration and hard to describe treble etch/harshness. The soundstage is wide but without depth.

SR-007 is a considerable improvement in all those areas, in particular the sense of depth and precise instrument placement that no other headphones I've heard can match. However there are quite a few people who think it can sound dark and 'unexciting' - this is to some extent helped by better amplification.

If you must get a Lambda type phone, I would definitely recommend a Lambda Signature - it sounds more open and resolving than the Pro, with less (subjective) weirdness in the highs.

 

[dvse]

Quote:

Originally Posted by Akabeth /img/forum/go_quote.gif Can anyone here tell me if any/all Stax headphone amps have temperature sensors...? or at least something to prevent the amp from getting damaged due to overheating?

Certainly not, but they would not overheat by themselves as long as there is sufficient air circulation (e.g. do not put a stack of papers on top of the SRM-717). You could also easily add a temperature sensor yourself

 

[macm75]

Pardon the interruption but hoping someone can explain how the bias works on a SRD-7/SB adapter. Just does not make sense to me - no AC in to rectify, the only input is from an amplifier output. Thank You.

 

[pdennis]

Hey folks,

Hope you've all been keeping -- I've been scarce because I broke my main rig during the summer, and since I haven't had time to deal with it, being on Head-Fi would just have made me very sad!

I'm hoping, though, that one of you folks will have an idea of what to do. Here's the sitch: I plugged my SRM-212A into a power source with the wrong polarity. I'm pretty sure I realized it right away and unplugged it without turning it on, but the unit still seems to be damaged (will not turn on).
My questions, of course, are: is it obvious what would have been damaged, such that I could go in and replace such-and-such a part to fix it? If not, will Stax work on it for me? I'm afraid that they might refuse because it's a Japanese market model, or that they'd charge so much that I might as well replace it.

OK, thanks for your help! Give me good news please.

 

[Keithpgdrb]

what are the audible effects of under powering a pair of sr-lambdas with an srd-7sb? here's why:
when I finally got my setup, I was finding that the upper midrange was very predominant, almost irritating on some albums. I also thought that the bass was a little weak. This is when I started asking about amps for the lambdas. I have since discovered that my amp was set for 6 ohm and under speakers. I have no idea why it was set that way. anyway, I put it up to the 8-12 setting that actually matches my speakers, and when I fired up the lambdas again, I found that the bass was improved, and the overall balance seemed better. I did however think that the high end seemed a bit tamed, or veiled. my first thought is, now that the cans should have enough power, is that the inferiority of my source is being revealed. any thoughts? please share.

 

[spritzer]

Quote:

Originally Posted by powertoold /img/forum/go_quote.gif Would someone please comment on the technical differences between a Lambda Pro and an O2Mk1 in terms of the sound? For example, so the imaging of the O2Mk1 is better, but do you have an analogy of how much better it is? It'd be great if you could point out other technical differences too!

The Lambda Pro is to my ears the worst Lambda since it does nothing well, the top end is harsh, midrange is recessed and the bass is flabby and loose, so comparisons to the SR-007 aren't exactly fair. There is also a variable with the L-Pro's, is the mineral wool (yellow sheet at the back of the drivers) still in place as that alters the sound quite a bit? The SR-007 does everything better and in a more controlled manner though it never flaunts its abilities to try and impress the listener. They suck you in over time like the true greats such as Quad ESL. The my favorite part is soundstage on the SR-007 as it is not terribly wide but can portray depth of field (which no other headphone besides the SR-Omega can do properly) with pin point accuracy.

Quote:

Originally Posted by Akabeth /img/forum/go_quote.gif Can anyone here tell me if any/all Stax headphone amps have temperature sensors...? or at least something to prevent the amp from getting damaged due to overheating?

There is a thermal fuse on the transformer that breaks if the amp is overloaded but that should never happen. The 717 is Class A so it gets rather hot but not as much as the 007t.

Quote:

Originally Posted by macm75 /img/forum/go_quote.gif Pardon the interruption but hoping someone can explain how the bias works on a SRD-7/SB adapter. Just does not make sense to me - no AC in to rectify, the only input is from an amplifier output. Thank You.

Well, the audio signal is high voltage AC after going through the transformers (1:25-30 ratio) so that's where the bias supply is drawn from. It is then fed through a zener gate to keep the input voltage a constant and a voltage multiplier. The caps are big enough to smooth out most slow points in the music so it works quite well. On the Mk2 SB units then there was another transformer mounted to the back of the chassis to supply a higher voltage due to the need for 580v bias. The transformer taps into the right channel if I remember correctly and the return lead is connected into the left. Easy really....

 

[krmathis]

Quote:

Originally Posted by spritzer /img/forum/go_quote.gif Well, the audio signal is high voltage AC after going through the transformers (1:25-30 ratio) so that's where the bias supply is drawn from. It is then fed through a zener gate to keep the input voltage a constant and a voltage multiplier. The caps are big enough to smooth out most slow points in the music so it works quite well. On the Mk2 SB units then there was another transformer mounted to the back of the chassis to supply a higher voltage due to the need for 580v bias. The transformer taps into the right channel if I remember correctly and the return lead is connected into the left. Easy really....

Thanks for the info Birgir.
I have been quite unsure how they have accomplished this as well. Now I learned something new..

 

[edstrelow]

I got my hands on a reasonably priced Stax SRM1Mk2 amp, from Europe, oddly enough. It is a B series with one regular and one pro socket. So far I am very impressed with what it does with the Sigma pro and Sigma/404: a wider and better defined soundstage and cleaner midrange and better dynamics.

The low bias plug didn't seem to help my SRXIII, but on the high bias ther SRM1 was definitely better than my SRM3's. There may have been a tad more bass on the SRM3 but that was probably not enough of a factor to make one prefer it to the older amp. EDIT: Actually with more time, break-in and warm-up I am also favorably impressed by the low bias outlet with the SRX3. It sounds somewhat better than my SRA12S preamp/headphone amp.

Odd that the newer Stax amps are not always an improvement over the earlier ones.

At any rate I should do some systematic listening, comparing amps for a change.

 

[Keithpgdrb]

so no insight into my earlier post?? sure would like some.

 

[Sherwood]

Quote:

Originally Posted by Keithpgdrb /img/forum/go_quote.gif so no insight into my earlier post?? sure would like some.

I'm not really certain what impedance the Stax adapter+SR-Lambda presents to an amplifier, but if you notice a positive change when using the 8 ohm taps then by all means, do so.

I can't imagine that your amp is underpowering them, let alone underpowering them only on the 6 ohm setting. Does the amp drive your speakers to acceptable levels?

My guess is what you're experiencing is not a lack of power, but rather the inherent sound of your system as it is. That's a bit of a cop-out answer, I know, but it's likely the right one.