[BenF]

L300 with L500 pads ARE L500 No?

Yes, except some changes in the headband.

I hoped you would have a different answer How much power SRM-253S has?

This setup has plenty of power for 009, I usually set both volumes around 12PM.

Also it costs around $500. For $500 you can get 353x, T1, SRM-1. They look bigger and more powerful. Does more power mean more bass? All I want is just to get more bass on L300 and I'll call it the end game for myself.

More power doesn't necessarily mean more bass.
The only way to improve L300's bass is to use the L500 pads (with the trade-offs described above).

 

[arnaud]

More power doesn't necessarily mean more bass.
The only way to improve L300's bass is to use the L500 pads (with the trade-offs described above).

While the pads are critical part of these headphones voicing, for estats, can’t deny beefier amps benefits in terms of bass control. Not clear myself if this comes from more power / headroom, use of regulated power supply, constant current sources in 3rd party amps though .

You surely are managing to keep things on a budget though

 

[tabness]

L300 with L500 pads ARE L500 No?


I hoped you would have a different answer How much power SRM-253S has? Also it costs around $500. For $500 you can get 353x, T1, SRM-1. They look bigger and more powerful. Does more power mean more bass? All I want is just to get more bass on L300 and I'll call it the end game for myself.

STAX confusing Advanced Lambda series:

start with L500
• L300: same sound element in L500 but different (thinner) pads and headband assembly and cable
• L700: L500 with "009 sound element technology" and different (thicker) pads and cable
• L300 Limited: L700 sound element (or maybe stators only and not membrane? conflicting information) and L300 cable/headband assembly/housing and L500 pads with glossier finish with gold badge
• MK2 (L500/L700): matte finish on housing and removable cable and metal headband assembly

AIRBOW 253 has the exact same specs as the 252S (280 Vrms blah blah blah) with "audiophile" parts. You can also buy the PAC 253 power supply instead of the wall power supply for a bit more power (never tried it but want to). Whether it sounds better than the 252S or not I've never compared directly to say. I had a 353X to compare with and the 253S and 353X sounded incredibly similar (identical?). 252/3 and 353 should have the same circuit, 353 obviously has a beefier power supply.

In usage, I never needed the extra power of the 353X for my L500 or 009S. Pretty much between 11-1 (clock) on the dial, usually closer to 11 on the 253 itself for those two phones.

For "more bass" depends on what you mean. If you want more bass extension, there are mods to seal the new Lambdas as they are by design not sealed for a midbass hump (I never did them someone else might be able to help more). If you just want more bass like midbass, I'd use another amp like the new 500 amp (T1/S/W/006t/S/II line) which is tuned for that rather than the linear 252/3/353/400 line. I found the T1S to be nicer with the Lambda anyway because it was a bit too bright for me.

 

[AudioCats]

.....
..... 252/3 and 353 should have the same circuit, 353 obviously has a beefier power supply.

....

according to people in the know, "The 353 is a srm717 with all of the extra transistors removed". (Google that sentence to see the original posts.)



by looking at the schematics.... 252 is a lower power version of 313; 323 is very similar to 313.

 

[BenF]

While the pads are critical part of these headphones voicing, for estats, can’t deny beefier amps benefits in terms of bass control. Not clear myself if this comes from more power / headroom, use of regulated power supply, constant current sources in 3rd party amps though .

You surely are managing to keep things on a budget though

This is one of the few threads where a ~5000$ setup can be called "keeping things on a budget"

...
AIRBOW 253 has the exact same specs as the 252S (280 Vrms blah blah blah) with "audiophile" parts. You can also buy the PAC 253 power supply instead of the wall power supply for a bit more power (never tried it but want to).

Airbow does have their own power supply - PAC-253, but it's 300$ and single output.
I use this LPS with dual output instead - https://www.aliexpress.com/item/DC5...-noise-DC-linear-regulated/1000004386010.html
I asked them to reverse polarity, provide second cable and upgrade to Talema.
Measured it with a multimeter - 12.06v

Whether it sounds better than the 252S or not I've never compared directly to say.

Using the LPS, couldn't hear any significant difference between 252 and 253.

 

[Menkau-ra]

Airbow does have their own power supply - PAC-253, but it's 300$ and single output.
I use this LPS with dual output instead - https://www.aliexpress.com/item/DC5...-noise-DC-linear-regulated/1000004386010.html
I asked them to reverse polarity, provide second cable and upgrade to Talema.
Measured it with a multimeter - 12.06v

Why do you need second output? Does the plug fit the 252S power socket?
Will my 252S with this LPS unit sound on the same level as 353x?

 

[BenF]

Why do you need second output?

I plug two amps into it.

Does the plug fit the 252S power socket?

The plug is the same as in 252/253, you just need to ask to reverse polarity - or buy this cable https://www.ebay.com/itm/201485015842

Will my 252S with this LPS unit sound on the same level as 353x?

Don't know about 353x comparisons, but with the P10 tube pre-amp, it gets me damn close to Blue Hawaii.

 

[codimension1]

The 3.6 ohms resistance is probably the DC resistance. According to spritzer, Stax used 1:25 step-up transformers, which means the impedance is reduced by a ratio of 1:625. Since the headphone load is largely capacitative, nominally around 100 pf, the impedance ranges from around 80 megohms at 20 Hz to 80 kilohms at 20 kHz, so through the transformer, the amp sees an impedance between 128 kilohms and 128 ohms - this means the tap you use is non-critical. Another way of looking at it is that the amp sees a capacitor of around 63 nf. You need an amp that is stable driving a capacitative load - most tube amps qualify. Stax recommends a maximum input of 30 watts (presumably into 8 ohms), so pretty much any amp will work. Note that this will produce nearly 1100 volts peak-to-peak into the headphones, or nearly 112 dB SPL at 1 kHz given the common rating of 100 dB output for 100 VRMS. If you don't want to exceed the max rating, you could choose the tap depending on the amp power rating. For example, for a 15 watt amp you could use the 16 ohm tap, for 30 watts use the 8 ohm tap, and for a 60 watt amp, you could use the 4 ohm tap.

The 30 WPC amplifier that I am using with the SRD-7 Pro distorts a bit on high frequency transients, but sounds great through the SRD-7 at other frequencies. Likely it does not appreciate the high (and capacitive) load resented by the transformer. Would it help to place something like a 10-ohm wirewound resistor across the taps on each channel (in parallel with the SRD-7 load) so that the overall load seen by the amplifier becomes more resistive (and lower impedance overall)? Since this will essentially also become a component of the step-up transformer circuit, I wonder if the change to the input impedance in this compound circuit would alter the tonality appreciably. (For example, I wonder if the impedance curve engineered into the SRD-7 is designed to compensate for some frequency response aspects of Stax headphones, and by altering this impedance curve, this change might alter that frequency response compensation.) Also, might the different time constant for the parallel resistor as compared to the transformer affect the phase relationships of the signal ?

 

[BrintaVett]

I'm trying to find posts where xlr input for SRM-1 driver is explained/discussed but having a hard time finding them. Anybody who can point me in the right direction?

 

[JimL11]

The 30 WPC amplifier that I am using with the SRD-7 Pro distorts a bit on high frequency transients, but sounds great through the SRD-7 at other frequencies. Likely it does not appreciate the high (and capacitive) load resented by the transformer. Would it help to place something like a 10-ohm wirewound resistor across the taps on each channel (in parallel with the SRD-7 load) so that the overall load seen by the amplifier becomes more resistive (and lower impedance overall)? Since this will essentially also become a component of the step-up transformer circuit, I wonder if the change to the input impedance in this compound circuit would alter the tonality appreciably. (For example, I wonder if the impedance curve engineered into the SRD-7 is designed to compensate for some frequency response aspects of Stax headphones, and by altering this impedance curve, this change might alter that frequency response compensation.) Also, might the different time constant for the parallel resistor as compared to the transformer affect the phase relationships of the signal ?

I don't know if putting a 10 ohm resistor in parallel with the SRD-7 will fix your distortion problem or not, but it probably won't hurt. There are a few amps that need an output load to be stable, and their manufacturers often recommend that they not be powered up without a speaker load connected. As far as I know the SRD-7 doesn't have any frequency response compensation for the headphones - that would imply that all their headphones have some common deviation that needs compensation.

Loudspeaker amps in general are designed to be voltage sources, more or less, which means their frequency response should be independent of load, since there is no way for an amp designer to know what loudspeaker it is going to be used with. Similarly, loudspeakers are generally designed to be (more or less) flat when driven by a voltage source amplifier. Of course this is all in theory, in practice it's a different matter, which is one reason that amps and loudspeakers can sound different when matched, or mismatched, with one another. And of course, for example, not all loudspeaker designers have the same idea of what sounds "flat." Not to mention, not all listeners have the same idea of what sounds flat either - some think the SR-007 Mk I sounds flat, others that the SR-007 Mk II sounds flat, others that the SR-009 sounds flat, and still others think the SR-009S sounds flat. And that's just among Stax flagships - they all sound a bit different.

 

[AudioCats]

I'm trying to find posts where xlr input for SRM-1 driver is explained/discussed but having a hard time finding them. Anybody who can point me in the right direction?

I don't think the srm-1 (either the old old version or the mk2 ) have XLR inputs....?

 

[JimL11]

I'm trying to find posts where xlr input for SRM-1 driver is explained/discussed but having a hard time finding them. Anybody who can point me in the right direction?

Perhaps that is because the SRM-1 never had XLR inputs to begin with. Prior to the SRM-T1S, all of the Stax amps had single ended RCA inputs only. Based on the schematic, the SRM-1 MkII has a diff amp topology input section (but used single-ended) so in theory it could be modified to take XLR inputs. But you would need to install XLR jacks in place of the RCAs, and you would also need to replace the dual pot volume control with a quadruple pot such as is used in the T1S and later amps (assuming there is enough room to take the additional depth of the quad pots. Then you would need to wire the volume pots to the diff inputs (one of which in each channel is normally connected to ground in the SRM-1 MkII).

Note that the Stax pots, whether single-ended or balanced, use concentric shafts to control right and left channels so the quad pot would need to have the same shaft arrangement - specifically, two of the four pot sections would have to be connected to the larger shaft, and the other two to the smaller shaft, in order to allow for balanced R and L channel inputs. I believe that Stax special ordered these from Alps, and that they are not available for the typical consumer, which means you would have to cannibalize one from a broken Stax amp. If it's a working amp, it's going to be a more recent design than the SRM-1, and already has XLR jacks as stock, so is likely a better choice than modifying an old SRM-1 anyway.

 

[tjlindle]

Freely admit this is a pretty silly question - assuming I get a good seal and swap the detachable cables, does wearing an L700mk2 backwards otherwise screw up the intended sound?

I've got the L500 and L700 on hand, I was going to post impressions vs. a couple vintage Lambda but I've just had a really hard time with the L700 pads. L500 is completely fine but the L700 gives me a pressure point right on my cheekbone that transforms into a headache after 30 mins to an hour. Wearing it backwards eliminates this completely.

I'm no stranger to this type of debauchery, I should post some pics of my Nova Classic. From what I can tell, it had had the yokes replaced...and the drivers were put on the wrong sides or something, which was "fixed" by reversing the contoured pads and putting them on the opposite driver. So it must be worn with the driver marked "left" on the right ear and vice versa (and this is fully correct - sounds intended to come only from stereo left or right will come from the appropriate driver), and as far as I can tell the pads are also backwards.

But it is actually very comfortable and it sounds good!

 

[DougD]

Freely admit this is a pretty silly question - assuming I get a good seal and swap the detachable cables, does wearing an L700mk2 backwards otherwise screw up the intended sound?

....

But it is actually very comfortable and it sounds good!

You have the headphones and ears. If it doesn't sound worse wearing them backwards TO YOU ... what else matters?

I find that wearing a baseball cap with headphones changes the head feel. (For me.) That's an easy thing to try.

 

[tjlindle]

You have the headphones and ears. If it doesn't sound worse wearing them backwards TO YOU ... what else matters?

I find that wearing a baseball cap with headphones changes the head feel. (For me.) That's an easy thing to try.

Well I agree 100% with that, if it sounds good then stop asking questions...but I'm curious if there is anything specific from a technical angle that actually gets messed up if you flip them around.

Re: a baseball cap, I already have a small washcloth folded twice-over that I put under the headband, otherwise the cups won't rest on my ears and will instead sink too low even on the lowest headband adjustment.

I guess I just have a smaller head than all of the Stax engineers

On the positive side the L700 are definitely the most detailed headphones I've ever heard. If the tonality here is halfway between the 007 and the 009, I'm not sure I'd want to go further towards the 009 though. At this point the only reason I'd do so is out of sheer curiosity at the level of resolution and clarity. I mean as far as I'm concerned, I can't imagine needing more than this. (EDIT: But that was also what I said after I heard the Nectar Pollinators lol, and look at me now...)

Also, even though it can drive the L700, the 353x is definitely showing some of its shortcomings. The bass in particular is pretty flabby, even after EQ it is more present but the flabbiness is still there.

I read that one thing the mafia amps really help with is bringing the bass under control - I can totally see that now.