What headphone amp to buy-Sennheiser HD 600?


Well, thanks to the kindness and patience of my fellow A'gon-izers, the hook-up "problem" for the headphone amp I have is solved. The amp is a Ramsey SHA 1. The phones are Sennheiser HD 600. I had remembered that amp sounding great. Now I'm spoiled by the new speakers I have, and even though the signal path to the amp is thru the Dodson DAC, I still think it sounds........not so great. Decent I suppose, but harsh on the upper end, yet without the mitigating detail, and you know, just.....unsatisfactory.

OK, OK, so here's the question(s): What's a great, fairly cheap (like, at LEAST less than a grand) headphone amp? Sonically, I want EVERYTHING!!!! (Except soundstage, that has never happened for me with any headphones, ever, I'm pretty sure not even with the expensive Stax I heard a few years ago).
It MUST have: Tight, deep, fast, smooth, tonally correct, musical bass, shimmering, non-fatiguing, emminently smooth yet ultra detailed highs, great midbass punch with no boom or softness whatsoever, midrange that is totally natural, smooth, detailed, and lacking any hint whatsoever of grain or electronic amplification artifact in the upper registers. It should sound great on ALL program material, from classical to rock to bluegrass to new age to jazz, anything and everything.

Other than those relatively modest criteria, there are no other performance demands. :)))

So, fire away!
mdhoover
I like my Portal Audio Panache headphone amp the best out of anything I have heard with my Senn 580s.

But mind you I have never heard a dedicated headphone amp.
I like my Portal audio Panache headphone out with my Senn. 580s. I know it is an integrated but I have heard it can compete with the big boys.
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Stay away from SS. Try the EAR Max or EAR Max Pro. Wonderful with the Sennheiser!
I would also recommend the CI Audio VHP•1 & VAC•1 combo. I recently purchased this setup after reviewing what was out there in that price range. An excellent headphone amp for the $$. And, I'm also using Senn. HD 600's.
You might want to try the Berning
It drove our Klipschorns with a beautiful, engaging sound, and when I listened on headphones, it was sensational. No, I don't work for Berning. I just want one!
The Gilmore amps sound great with the Sennheisers:

http://www.headamp.com/home_amps/index.htm

I was very impressed. Like the combo more than with the Berning MicroZotl (which I have). See if you can read more on other forums. Also consider a cable upgrade, if there is any $$ leftover.
Thanks for all the responses so far. Checked out all the above links and may make some calls too.

Forgot (!) to mention that remote control would be really nice, if at all possible. Any ideas for that? Also, not absolutely locked below 1 K, but not interested in going totally insane either. Would only go above that level if the product offered VALUE, i.e., sound was worth the price.

Any additional ideas are appreciated.
I have the Earmax and I think it sounds great with the HD600's. For your price range you can upgrade to the higher output Earmax Pro (not that you need it with the HD600's). The bigger advantage of the Pro is that it has a more common tube set making it easier to delve into tube rolling. FWIW, I have not felt the need to change the tubes on my Earmax at all, i.e. very satisfied!!!
I suggest you check out the website Head-Fi.org for all things headphone, found here. Lots of good info along with the ususal bits of noise.

Bob
I'm VERY happy with my WooAudio3 driving my HD-600 cans.

Here are some other folks who like 'em too:
Audio Review WooAudio 3 reviews

Sorry, no remote, but you can use it as a preamp too. Not as good as my BAT VK-51SE, but it doesn't embarass itself either. That's saying something when comparing a $470 'preamp' with a $9000 one.

Have fun,
John
Another happy CI Audio VHP-1/VAC1 user with Senn 600s and Cardas cord.This is really great for the $$$. Previous was a Maxed Out Home Headroom amp.
After lots of experimenting I've landed on the Berning ZOTL. Nothing else came close, and when I rolled tubes it got even better. Enjoy.
Joe
Just to add a bit to the input above: I have a Portal Panache, and a Berning Micro-Zotl. I don't use your cans, but a pair of Sony MD3000's. The difference between the two amps is not subtle, and though the Panache has a decent headphone section for an integrated amplifier, it just doesn't approach the smoothness and refinement of the Berning. Listening to the two A/B I do not want to listen to the Panache very long, and it doesn't take golden ears to hear the difference (love it as an integrated amp though). I cannot speak to the synergy with your cans specifically, but if they are the same cans Peter brought over (one of the Senn cans I'm sure) I didn't much like them in comparison to the Sonys, for whatever that is worth. The Senn's I heard sounded much less lively and dynamic than the Sonys on the Berning. Peter can say which model they were. So, as Peter indicates, it may be a matter of Synergy...or? Peter has both Senns and Sony so he could speak more to that.

Marco
I have a pair of HD600 and I'm running them through a Bottlehead SEX amp. If you have any interest in DIY, I would HIGHLY recommend this amp. It's hard to beat @ $369.

Even if you're a little hesitant of DIY, the Bottlehead community is extremely helpful. The build is well documented and straightforward and Doc is def. one of the good guys out there. The amp has almost unlimited upgrade potential if you're so inclined.

Cheers,
Hat

Here's a link...
http://www.bottlehead.com/et/adobespc/S.E.X./SEX.htm

Cheers,
Hat
Sorry for speaking out of turn here, as I heard Marco's Berning amp with his Sony headphones, not with the Sennheisers. Loved that combo, however!
I had the Sens 600 and sold them to buy the Sony/Berning combo. The Sony/Berning combo is quite good, very lively and dynamic. Later I heard the Sens with a Cardas cord and the Gilmore amp I mentioned and it was great too - more neutral than the Sony/Berning combo. The preference was a matter of taste. However, we did a headphone shootout with several Gilmore amps and the Berning, and the Senns definitely sounded better on the Gilmore: have them upgrade it with stepped attenuators for the volume control, keep the circuit as simple as possible (i.e. if the model has a preamp out, you may want them to build it without that). I only say that because that is the configuration that I heard that sounded best with the Gilmore.
I love my Grace Design 901 headphone amp/dac. I'd suggest looking into the newer m902. it's probably a little more than you are looking to spend (I think list price is 1600), but it is the best headphone amp I've heard.

for easy reference:
http://www.gracedesign.com/
Before you spend a lot on an expensive amp, swap the HD600s for 650s. It is a night & day difference, a much more open sound with far better separation of musical components. The 650s are about $350 (street price from a Google search), an incredible bargain. Then,
get a good headphone cable like the Zu Mobius.
I use an old Headroom Max with fine results. It competes favorably with my tubed Stax Omegas -- not quite the same midrange purity, but a fine combination of relaxed, refined sound with just the right amount of detail, very comfortable and great for long-term listening with no fatigue or bordeom.

Interconnects make a big difference, with Kubala-Sosna Emotions the best I found for the Max but Cardas Golden Refs performing well for the price.

There is a new Max out for $3K I have not heard (with good reviews on Head-fi), but I think Headroom has some of the old ones left.
Rgs92:

It's funny that you should mention the Stax line. I MAY have a line on some older but well cared for Stax Lamda Pro's, complete with a Stax vacuum tube amp ON THE CHEAP. Or, maybe not. Not totally sure yet.

So..........No remote, but I COULD buy reeeeeaalllly long Jaguar RCA's (5 meters) for 800, and MAYBE get these "earspeakers". Never thought I'd be able to afford high end Stax. Had been totally off my radar screen (I'm NOT Bill Gates, ya know....).

Any thoughts, IF it even materializes? Everyone, please, feel free to chime in.
p.s. to all kind and helpful A'gon-izers posting to this thread (which is HIGHLY appreciated, by the way): I didn't hear about this Stax steal "possibility" until today (12/23/05), AFTER starting this thread, and it may or may NOT be true (seeing is believing). So that's why this Stax question is added to the thread just now.
I found that the Stax phones which are circum-aural (they totally go over your ears and "seal" to your head to make my ears and head sweat! YMMV. The 650s are better than the 600s and the aftermarket cords are a real value. If you do end up with the Stax (which sound lovely), and want an extension headphone cable, drop me a line.
Give P.S Audio a listen.Normally I would say "TUBES" given they need almost none and one can roll them to there hearts content.But reading the Stereophile review of the new Intergrated and seeing there web site if you have then nearby give then a shot.Sounds like some pretty cutting edge tech going into more than there power conditioners.If theye made a table I might do a linn,Naim,Rega,thing with them and go with a one brand system since it's voiced together.but might go with the cebter and stick to Sony/VPI and something as the ultimate transducer at the speaker end.
Happy Holidays
Chazzbo
Wow, given so many opinions it sounds like alot is left to personal taste or not alot of comparative listening. You may have to do the comparitive listening yourself, or go to the headfi.com forum and see what the total headphone geeks say!
I do like Headfi.org as a resource too. My only reservation about it, and this is a gross generalization (I hope), but in reading many posts there it seems to be a much younger crowd, and or a crowd that has different musical tastes than my own. I'm sure there are exceptions, but I don't read them much. It seems to be a much smaller crowd than Audiogon, which is understandable given the narrowed scope of the subject. The types of music used as resources for Headphone reviews there are often nothing I'd listen to much myself. Just to be sure, I just went over there and right away found this recent thread on what folks there used as source material to test out their new cans. There are currently 47 responses, so it is a pretty wide sampling, yet the general trend is toward music I rarely listen to (rap, electronica, pop, the occasional typical audiophile recordings...Krall, DSOM, blah, blah...but mostly much more dynamic, poppy, rock electronic stuff). Is this a fare reflection of headphone use in general at this level, or just those who choose to spend time writing about it on online forums do you think? BTW, I mean no offense at all to those who have different musical tastes, they simply are not mine. Speakers/Headphones that sound great with Electronica, Pop and Rap are not necessarily going to sound superior with Accoustic, Folk, Vocals, for example. Bottom line is, like with what I read here, I take what I read with a large grain of salt and do try to read as much as I can elsewhere as well. I still would not hesitate to recommend Headfi.org as a good resource. But it is a different crowd in general than those I see posting here. I'm sure there's crossover, but I get a strong impression that it the two camps are quite different nonetheless.

Marco
Quick update: Stax Lambda Pro headphones and some sort of a matching Stax Tube headphone amp to be dropped off at my house for auditioning on Monday evening, 1/9/06. Swampwalker, or anyone else--->any thoughts? Thanks.
I had the Lambda Pros with a Stax 006t and liked it very much, except for the aforementioned sweating problem. Be aware that if you tube-roll the 006t, the biasing is a rather complicated procedure that involves iterative adjustments. If you decide you like it and want a near new hp extension cable, let me know. I can't remember why, but I think I preferred the Lambda Pros to the newer 404 series phone. I prefer my AKG K1000s driven by a Cary 300sei, but thats quite a bit more $. You will find the Stax to be more detailed and more forward than the Senns, but I found the Senns to be much more comfortable.
Swampwalker,

Hey, thanks for the quick reply! You said:

Be aware that if you tube-roll the 006t, the biasing is a rather complicated procedure that involves iterative adjustments. If you decide you like it and want a near new hp extension cable, let me know.

I know this is an ignorant question, but what the heck is TUBE ROLLING? I'm assuming it's different than "cow tipping"......
Cow-tipping-- you're not from CT are you? that was rumored to be a hoot of a prank back in the 50s at UCONN! a bit b4 my time, but not that much. Tube rolling is switching to different brands of the same type of tube (and there are often numerous "equivalents" that may or may not be exact matches, to try and tailor the sound to your liking. In a power amplifier, that often requires manually adjusting the voltage to the tubes because they have slightly different electrical characteristics. NOS (New Old Stock) tubes are often considered superior in sonics and longevity, and command a high (sometimes exorbitant) price. There are many counterfeit/rebranded tubes out there so sometimes, it is a bit of a crap shoot.
Swampwalker:

Tube rolling sounds like a pretty intense undertaking. I may have to wait a while before going to those lengths. Checked out the Cary site and tried my best but couldn't figure out what the Cary 300sei is. Any further hints would be appreciated. Another A'gon-izer has ALSO recommended the AKG 1000's, so it may necessitate a look-see.
Tube rolling sounds like a pretty intense undertaking.

Hey if you can tip cows over at night, then tube rolling ought'a be a breeze! No meadow muffins to look out for either!

Because you are talking about a headphone amp that will likely use only a few, smaller tubes, you may be making it seem more complex and expensive than it actually is. Headphone amps are mostly auto-biasing so you don't have to worry about constantly adjusting the bias. With a tube amp it is basically a plug-and-play scenario with swapping the tubes. As Swampwalker indicated, some of the NOS tube prices are as out-of-hand as real estate in Manhattan. But you really don't need to go there to get satisfaction and great results from trying different brands of tubes. Once you choose and amp and are familiar with the tubes it uses, just do some reasearch here and on other Internet forums as to what others with the same amp have preferred. There are a few really excellent sources of new and NOS tubes to consult as well (The Tube Store, Vintage Tube Services, VTV, Upscale Audio, to name a few). You don't have to spend a fortune on NOS tubes - there are current production tubes that arguably have the potential to perform just as well if not better. Anyway, just don't rule it out...on a headphone amp it's no big deal.

Marco
From your description, you're describing the SinglePower headamps. Especially the MPX3 model with the Slam modifications.I've tried it in my main system and it sounds as you describe. Different tubes change the sound instantly.
The 6SN7 and 5687 tubes are a good mix and give you a taste of tone and transparency.
My profound ignorance regarding tubes is becoming increasingly apparent to me. Yikes! This is downright embarrasing! I know nothing about this topic--->NOTHING.
My profound ignorance regarding tubes is becoming increasingly apparent to me.

No call for embarrasment at all. That's pretty much where most of us started. If you've read the responses so far, then at least you know SOMETHING. Besides, with much of the plug-and-play, auto-biasing circuits designed into most headphone amps, preamps, and many power amps, you really don't need to get much beyond Big Bird and Ernie to enjoy what the potential of tubes are in audio gear. Just use the two ears you've got and make your own decisions. Who knows, you may prefer SS...stranger things have happened. Seriously, there's plenty of folks who go that direction. For me tubes, at their best, have an ease and a natural, lifelike presence that SS can only strive for but never quite reaches the same mark. Yet I've heard SS amps I've really enjoyed for what they have to offer that tubes cannot. Or perhaps a hybrid solution that utilizes both tube and SS technology. Go out there and listen. Pick your poison and enjoy the music. Another option is that many of the head amps are available on a short trial period (7-30 days usually) from either manufacturers or dealers. You may be able to get a few and compare in the comfort of your own home. The only drawback there is that the sound may change, either subtley or profoundly, as the circuits burn in with use. Tubes also change after an initial burn-in. So you may be missing out on some aspect of performance without a burn-in period. If you are in a vast metropolis, just find a local dealer who might have some examples and bring your cans and your music. A local audio club may be another option. Or plead here on this forum for other members in your area who may allow you to come listen to their gear. I'd bet you'd find one or two who might be willing, since you are an established member.

Have fun!

Marco
Marco:

Thanks for the advice. There will certainly be a learning curve with this, that's for sure! Duane had me try a tube preamp a little over a year ago on my system that had a B&K ST 140 amp, Paradigm Studio 100 V3's, and the Rel Storm 3. The tube amp was anemic in the bass with that setup, so I returned it. (See footnote) Anyway, I haven't tried tubes since, but will be doing so with these Stax Lamda Pro's, and their associated vacuum tube amp.

FOOTNOTE: It's the ONLY time I can remember Duane not correctly predicting whether I'd like or dislike some audio thing--not a bad track record for Duane, huh? This has been true even for things he didn't personally sell!
Duane sounds like a good friend to have. I had a B&K EX140 which is the dual-mono version of yours. It is most definitely a kinder gentler version of SS with a softness that many folks like to call "tube-like" while still delivering the SS goods (you mention that tighter bass line). There are SS amps that can do all that even better. I'm really enjoying my simple Portal Panache, which puts out the same amount of power. Though I wouldn't call it soft or warm, it is very engaging and enjoyable. So I haven't given up on SS stuff altogether. I've never heard the Stax, but I know they have a reputation of being a very unique headphone. Let us know what you think.

Marco
Md- The 300 sei is a 300b-based, single ended integrated amp with a headphone jack. The 300b output tubes are expensive but it has great midrange and since I mostly listen to acoustic instrumentation and voice, its a good match. The AKGs have a very unique "form factor" that some people cannot abide and which generally are driven straight off speaker outputs of low power amplifiers (4-10wpc) due to their very high impedence.
Ah, sorry I missed that you might be rolling 300B's. WhooHaaa, then you are talking some bucks. Still many amps using those tubes are auto-biased as well. Actually I've recently been doing a bit of rolling in my 300B amps and have really been initially very impressed with the new Svetlana tubes that are only around $240 pair from CONUS in Canada. They offer more detail, clarity and impact in the midrange on my rig, at the expense of some of the overall balance, and do-everything-right of the WE 300B's that I've grown accostomed too. I wasn't at all fond of the TJ meshplates...just overall too soft. I could happily live with the Svets. WE's still rule to my ears, but not such a clear winner in comparison with the new Svets. Yes, rolling tubes in a 300B amp can be an expensive endeavor.

Marco
Consider also the Singlepower range of headphone amps or the headroom amps for a lower budget.
If you have those high demands get the AKG K1000. I own Grado RS-1 and Senn hd600 (heard the 650) - I heard the K1000 and end of story it was in another league altogether while creating a soundstage outside of the head (by a little bit). If you can hear them do so before centering a system around the Senns. I wished someone would have told me about the AKG's before I went down that road.
I highly recommend the Singlepoweraudio.com tube amps for the Senn. headphones. I have owned or heard the PPX3, MPX3, SDS, and the SDS-XLR balanced amps. The base models are the best headphone amps I've used, and the owner will custom build any amp to your phones or needs.
Robm321, and everybody else who has contributed to this thread so far:

Thank you all very much. Headphones are a whole new realm for me.
Sugden Headmaster, it fits all of your requirements I guess: solid state with tube-like sound, built with HD600 in mind, remote, excellent line stage as well, Stereophile Class A headphone amp (for what it is worth), about $700 used. Only issue is to find one second-hand. I had been looking for one for over a year and found one on Agon...I was read number 8 on the Ad and bought it right away! I sold it since (no time for headphones) to someone who had been looking for one for 18 months...no depreciation, I can tell you this!

http://www.onhifi.com/product/sugden_bijou.htm
Quick Update, and request for additional opinions:

I just listened to a Stax Lambda Signature Pro System using the Stax SRM T1 dedicated vacuum tube amplifier. The signal is routed to the headphone amp thru the same player, dac, and preamp as the Intuitive Design Summit Loudspeakers and the Rel Storm 3 sub bass unit are.

The phones don't express the bass as well as the speakers driven by the Odyssey Extreme monoblocks and supplemented with the Rel Storm 3, but my guess is that I shouldn't expect that. They aren't BAD in the bass and it's certainly tolerable. There appears (on initial listening) to be a touch more detail, but not nearly as much more as I had expected: the difference is not that impressive. Furthermore, the high end is not as sweet as the Summits', but it isn't TOO harsh, and my guess is that the vacuum tube output stage is helping in this regard. Midrange proficiency seems overall similar between the Stax and the Summits; there MAY (or may not, I can't be sure yet) SLIGHTLY better midrange detail with the Stax, but timbre and tonality MAY (or may not, again) be SLIGHTY better on the Summits.

I'm sort of (but not really, I guess) surprised that the Summits hold up so well against these esoteric electrostatic headphones, and in fact, the Summits plus the Rel are CLEARLY the preferred listening mode, especially when soundstaging and bass reproduction are factored in. However, in the other areas mentioned, these seem to be at least close to the Summits, so they should be listenable in the long term (at least during the short interval between when my wife makes me turn off the Summits after 9:30 pm on school nights and when I go to bed).

All of the above having been said, here's the decision to be made: whether or not to purchase the Stax Lambda Signature Pro Earspeakers plus the SRM T1 vacuum tube headphone amp for the price of $850, all inclusive. I'm told that this 10+ year old system (which is in very good condition, by the way), originally retailed for about $2500.

So, what do you guys think? In the absence of strong advice against it, I'm about to pull the trigger.
Marco:

You said:
...the new Svetlana tubes that are only around $240 pair from CONUS in Canada.

Holy guacamole! "only" 240 clams, for a pair of TUBES?? Just how long can these tubes be expected to LAST (I'm reeeaaally hoping you say at LEAST a year or more)?

Are tubes really that expensive? GOLLY!
Holy guacamole! "only" 240 clams, for a pair of TUBES?? Just how long can these tubes be expected to LAST (I'm reeeaaally hoping you say at LEAST a year or more)?

Well, yes, they should last at least a year. I don't know about the Svets, but the WE's are rated for around 10,000 hours. But if you think the $240 price tag is pricy, you don't wann'a go there! The Svet's are aiming to be, at least structurally, a copy of the very popular WE's. In terms of sonics they sound different indeed on my amps. The Svets have a crystalline mid-range, striking in that effect...almost etched. The WE's give up a bit of that kind of sharply focused clarity for a better overall balance throughout the range (IMO and in my amps) reaching a bit more into the lower registers and delivering better detail there as well as in the highs. But that Svet midrange is pretty amazing...I was very impressed with them.

I forget how you got into 300B amps...was it you or someone else suggesting a Cary? This started out as a headphone amp thread....now if you are still looking at headphone amps that utilize tubes you don't have to worry as much about dropping that kind of coin on tubes, as most use smaller, less expensive tubes. If you are listening to your headphone amp to supplement your main system then I'm quite sure your tubes there will likely last you several years before having to change them. My MicroZotl takes 2 12AT7's and two 6SN7's. Total cost to retube is about $80 for some nice NOS stuff. You could spend more, and you could spend less depending on what you're satisfied with. Kind of like buying wine in a way. The tubes definitely have different flavors which can be more or less accentuated by the actuall circuit/component they are going into. There are tube amps that just use two tubes as well...even cheaper to retube, and not necessarily better or worse than amps using more tubes, bigger tubes or different tubes. Certainly they'll all sound different...but it is really up to you to decide which you prefer.

Marco
Marco,

It's beginning to look like I'll be using a Stax SRM T1 headphone amp to drive a pair of Stax Lambda Signatures, {{{{{although I now understand what Swampwalker meant about the "head sweating" problem!! }}}}}. I haven't read the manual yet, but they sounded better this morning after the amplifier, which has a vacuum tube output stage, was allowed to sit overnight plugged into my system with the "power" switch turned off, but the "pre-warm" switch turned on. I don't even know what kind of tubes it uses.

Stax questions:
--How expensive are these to get serviced, particularly with respect to the diaphragms?
--Given what I said (in the post before the tube sticker shock post) about their sound, does this seem like a reasonable way to go? {{Swampwalker?? Others??}}
I don't even know what kind of tubes it uses.

I believe it uses 6CG7 (also 6fq7) - fairly common and not expensive. My preamp uses (only) two of those tubes and I like it very much.

No experience with the Stax stuff to comment on.

Marco
Md- Only you can decide about the ergonomics. The 6fg7 aka 6cg7 tube the stax uses is inexpensive. the SRM-T1 amp, IIRC is an older amp as are the Lambda pros and you should know that b4 you buy; also that service is provided on properly imported Stax cans by an outfit in Canada that provides good service, but occassionally they have to go back to Japan which as you might guess is expensive and slow. Gray market goods have to go back to Japan. If the amp works on 110 VAC w/o a transformer, it is most likely an authorized US import.
The 300b tubes came into the conversation via my recommended amp for the AKG-K1000s which are a very high impedence, unusual form factor hp that requires a speaker level signal of 4-5 watts or more.
Swampwalker:

As for the "gray" areas of the Stax marketplace, the pair I'm coveting are offered from the original owner, who purchased them from an authorized US dealer, so that won't be a problem. It's a great heads up in general, though. Price of repairs still COULD be a problem, and that's why what you said about the 404's is so interesting.

You said:
I can't remember why, but I think I preferred the Lambda Pros to the newer 404 series phone.

How big of a difference did you discern, if you can remember? The 404's appear to be the successor in the Stax line to the Lambda Pro Signature, although maybe that's wrong. In any case, the 404's can be had NEW for $499 at AudioCubes. So they could be an alternative if the price tag for repair of the Lambdas gets out of hand in the future, UNLESS you can remember something really bad about them......which is why I so selfishly ask you to jog your memory.
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Robm321 and Swampwalker:

It sounds like both of you, and many others, are impressed with the AKG 1000's. Do you think they'd work with the Odyssey amplifiers I have? What about the bass response of these?

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Marco:

You said (and Swampwalker too, but these are your words quoted):
I believe it uses 6CG7 (also 6fq7) - fairly common and not expensive. My preamp uses (only) two of those tubes and I like it very much.

Not to sound like TOO much of a cheapskate, but how much is "not expensive" from your perspective? Also, what about "tube rolling" with THESE tubes???
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EVERYBODY:

Thanks a lot for sharing your knowlege and experience and your patience in doing so! Every single post to this thread has been helpful in some way! (See optional footnote, if you want to...)

{{{{OPTIONAL footnote: This thread is fun--at least for me, maybe not for some of you (!!!)--but also it's demonstrating to me how little I know about tubes, and it's a strange feeling to confront my own ignorance on this topic: Marco, your kind words regarding my confessed "tubal retardation" are very much appreciated.}}}}
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