The vintage Ortho thread

I couldn't settle back down with old flabby bass, so sealed cup grills with micropore tape.

Switched to 95mm pads because smaller pads are too uncomfortable for extended listening (85mm pad foam is narrower with less surface area for spreading pressure).



Like with the Yamahas adding more damping makes more apparent the treble peaks. In exchange I get faster transients and tighter more extended bass until eventually bass starts to stiffen and fall off. Another side effect of damping is shifting upper mids dips. The T30 treble peaks are not problematic yet, so I'm going to see how much more damping I can add before it does become an issue. Before hadn't explored too much damping limits because I removed that front felt filter circle and it made treble peaks unbearable. Now I can go full ahead damp.

Next, seal cup grills with electrical tape. Front baffle still tiny bit leaky though so not a full-seal which is probably for the best.

 

Sealed grill. Extra damped bass is extra interesting but now there is a 2kHz hump. Not sure if its overdamp or reflection. Didnt expect to work anyway - just curious. Had to switch to high gain on Vali2 to get measurements. You can see the micropore left from yesterday’s experiment which sounded pretty good.

 

I just noticed user bucketinabucket from HF is @Ariamella here. Aria sold me their spare RP18 (HF classifieds). Hey!

I just messaged @purr1n for his participation in a vintage ortho tour. Headphones provided by me, @dBel84 , and @rhythmdevils (?). Maybe you'll see your RP18 Aria. @Vtory , @Hands , and @cskippy also welcome. Tour still to be organized but please contact if interested aforementioned users. Sorry others, keeping this tour concentrated to most prolific reviewers and measurebators @Merrick you can at least get my stuff afterwards and keep YH-1 if you like - I don't want.

 

Just got my stock YH-1 re-terminated to balanced. This thing still rocks.

 

^ Fostex T30 drivers in HFM HE400s enclosure @YMO @ext1


^ NAD RP18, drivers moving to Beyer DT880 Premium enclosure next.


^ YHD-2 (bottom left) belonging to @dBel84 . I got lucky with a nos YHD-1 (at top left and below pic). Fostex TH500RP (at top right). Speaker to headphone adapter by dBel84

 

Nice transpant @Philimon ! Does the T30 driver sound better in the Hifiman frame?

And does your RP-18 have a rattle? It might not show up until modded because it only shows up with certain frequencies. The more bass the worse it is.

 

T30 now sounds much more open with a larger soundstage. The larger HFM focus-a pads have a big influence as well.

I’m surprised RP18 didnt blow me away compared to T30. @takato14 describes his favorite headphone the Sansui SS100 (king vintage ortho) as an amalgam of T30 + T50 drivers, so T30 maybe has some characteristics that RP18 kapton does not necessarily better. I’d say the T30 is slightly bassier and more linear and smoother sounding overall. RP18 has a tiny upper mids bump that doesnt appear to go away even with transplant mods. RP18 does have a slightly bigger driver and larger stage.

RP18 still hasnt been modded yet though besides pads. I tried moving to the DT880 today but the stock screws on RP18 driver baffle are a little in the way of sitting flush in Beyer enclosure, so Im going to replace with some countersunk screws.

RP18 does not have bass rattle! It does have another issue though: one of the drivers has a couple tiny indententations on the membrane. Measurements show an earlier bass roll off on this driver vs the other channel. The earlier roll off starts around 50Hz, while the other channel doesnt start to roll off until ~30Hz. Do you have an extra working kapton driver?

My T30 now has the exact same issue too described above. When I was soldering I splashed a droplet onto the membrane which left a tiny indent. So now that one channel rolls off a little bit earlier. I tried googling if a small bass imbalance would be terrible, but gave up searching because most discussion was about speakers and a lot of points didnt apply to headphones and then I got bored.

I tried test tones and thought I could hear the measured imbalance, but I may just have a too easily influenced mush brain. Listening to a few hours of music and testing specifically for bass and I could not determine there being an imbalance with familar music (maybe I didnt listen to the right music). I bet it has an effect on the sound even outside bass response but I couldnt tell from listening.

 

Waaaait @rhythmdevils . Your RP18s only show rattle post mods? But stock they are fine? Why not put them back stock and enjoy or sell?

 

I'm not actually sure they don't rattle stock but the diagrams don't move the same way stock and they put out way less bass, I'm just assuming. I wish your pair was in good health, I'd mod it for you and we could try to figure out if this rattle is systemic or I just got unlucky.

It's amazing how good they sound compared to today's orthos, really not far behind despite being 40 years old.

 

Im a bit foggy but I thought I came across some posts in ortho roundup where someone shared pics that addressed the buzz/rattle by adding in some spacers. There wasnt much description and I didnt read much further around that post since I was searching* for some other information. The user didnt call them spacers, but thats what it looked like to me. Preventing two things from touching. Dont remember how or where spacer was placed. The RP18 was completely disassembled. *(I searched: “RP18”, “RP-18”, and “T50”.)

 

I'd put a tiny bit of tape to block the hole, it may help retain bass pressure.

 

iirc this was on the megathread on HF and addressed the newer T50RP ( but for those who know me and my very sporadic recall will know that this might be way off base )

..dB

 

Luckily, no hole, just a dent. Lesson learned: place tape over drivers before soldering wires to connection tabs.

They are amazing for 40year old drivers, but years though since Ive heard an Audeze or the OG HFM. If Verum owner wasnt an apparent dick Id buy again to try the updates since last. And Id love to try a new Audeze LCD2C or Hifiman HE6se sometime soon @rhythmdevils . Small budget audiphile though so have to go slow. I want to try that ETA Supra as well. The GenG bass was fantastic (apparently only for low volume listeners as distortion increases quickly with spl). Wonder how it compares to TH900 modded bass @E_Schaaf .

 

Started searching for buzz / rattle fix for you @rhythmdevils . First related post but not the one I was thinking about with spacer solution or maybe I wont find because dBel says I was probably remembering an old T50rp fix and not one for RP18 which I dont completely doubt because I do have meh mehmory.:
https://www.head-fi.org/threads/orthodynamic-roundup.111193/page-1679#post-13831323

 

Wrong. I only listen at high-ish SPL and those readings were done with old poorly cut foam with inconsistent seal so they are not indicative of the actual performance. I can virtually guarantee we'll get a better reading next time. There's a reason those readings weren't publicly posted and I'm sure 1.1 tweaks change the ballgame. The majority of those who have heard them have lauded the bass quality from a subjective standpoint including at high SPL.

TH900 bass I'd say is comparable. Supra bass rolls earlier but is more sub-localized. This is all off topic for this thread! Moving on...

 

My old MK1 (should be MK2 technically, but maybe MK1 ver. 2.0). Basically they look like normal T-20s of today, but have the circular orthodynamic driver, vs the square driver that is smiliar to the one in the T-50.



The only mods -

• modeling clay on the plastic housing in the back holding the driver
• polyfill in the rear cups
• bottom ports blocked with felt tape
• ZMF Ori pads

The biggest thing with these is getting clean bass without just killing the treble air and not being over-damped. Pads can really change things. I had Shure SRH840 pads on before because it has a substantial foam in front, but the bass was still not enough.

 

T30 bass imbalance was from bad pad seal. HFM pad mountung mechanism is the worst.

RP18 may not have an imbalance either! Previous owner reassembled the drivers backwards causing a gap between driver and front baffle. The gap is also asymmetrical…

@Azimuth Nice work. Keep going. And a comparison to T50RP please if you got em.

 

@Philimon i wouldn’t worry about a little measured imbalance in such deep bass. Channel imbalances are very hard to hear at any frequency but your music probably has no information down there anyways. If it sounds good don’t fret it.

 

! O.O !
The officially deemed lost by HK post RP18 @Aria sent to me 4months ago suddenly arrived. Package did not appear tampered or damaged. This RP18 is nicer condition than other. Not tested yet.





BTW I bought a parts HFM 4XX for other RP18. Much easier than Beyer Premium DT880 transplant mod and more secure since driver is held in with screws instead of friction.

 

Already modded by Aria (seller), don't know all the details. And the pads are old HFM velours. Imbalance in measurements is typical and normal... Not listened yet except to see if they work.