Any Seas H1212 designs?

**JonMarsh** · 04 August 2005, 17:24 Thursday

Well, stay tuned, because I'm workling on something similar for a friend, and adapting it to the H1212 is pretty trivial. Same woofers and midwoofers.

~Jon

**Jim Holtz** · 04 August 2005, 17:58 Thursday

You are the man!

Hi Jon,

Excellent! I'm building the Natalie P. for a temporary solution but I'd really like to do the 3-way with the RS drivers using the H1212 for my daughter. I think the Natalie P. will be a good companion to a very nice Shiva sub sitting in my store room that I've been unable to sell individually. The Natalies should integrate nicely. I also need something new and different to take to the Fall DIY events too.

I'm looking forward to seeing what you come up with. Thank you for the pro bono contribution you make to the DIY community! I do appreciate it!

Best regards,

Jim

Originally posted by JonMarsh

Well, stay tuned, because I'm workling on something similar for a friend, and adapting it to the H1212 is pretty trivial. Same woofers and midwoofers.

~Jon

**JonMarsh** · 04 August 2005, 21:29 Thursday

Thanks for the kind words, Jim. Now all I've gotta do is another hat trick!

:B

**JoshK** · 05 August 2005, 10:24 Friday

Is the H1212 the new budget king? Trumping the H1189? I've seen Jon mention it a few times lately but it is the first I am hearing of this tweeter.

**JonMarsh** · 05 August 2005, 16:06 Friday

Well, it's even a skosh lower in distortion than most RS28A or 27TDFC, it's flatter than the 27TDFC (doesn't have the slight upperend emphasis), and it's pretty much a drop in.

What's not to like? Those with the 27TDFC shouldn't run out and replace their tweeters in a frenzy, but if you're doing a new system, it's something to think about. I am a hard dome fan, personally, so I may "upgrade/Sidegrade" my 27TDFC speakers. Already did that with the origninal Modula MT.

~Jon

**JoshK** · 05 August 2005, 16:18 Friday

Then do you see the Arvo Part using the H1212 instead of hte RS28a?

**DearS** · 05 August 2005, 19:46 Friday

what does the Arvo project look like nowadays.

**JonMarsh** · 05 August 2005, 21:29 Friday

Originally posted by JoshK

Then do you see the Arvo Part using the H1212 instead of hte RS28a?

For now, no. I already have crossovers built suited to the SS98000 and RS28A, and the impedance of the H1212 is different, and would require a complete rebuild. It's advantages are NO where near that siginficant to justify that kind of expense and effort- in most cases, I think even pretty good listeners would be hard put to hear much difference in an A/B comparison.

The only thing I plan to evaluate yet for the Arvo's are the 830884's. Then, if I want to be really annoying, I might also get some W18's to try. But the crossover impelmentation will also be completed (I think it essentially is now, anyway) for the M8a. I like what I've heard with the M8a and RS28a combo quite a bit.

~Jon

**LNeilB** · 06 August 2005, 00:06 Saturday

It's superb

The most relaxed, accurate and transparent tweeter I have heard (though I've not heard the megadollar tweets). It doesn't have the usual nasty metal dome sound. I'm guesing this can be attributed to the extremely low distortion and energy storage specs.

Buy them.... :T

**JonMarsh** · 06 August 2005, 10:44 Saturday

Agreed. :T

And welcome to HTGuide.

~Jon

**Mark K** · 06 August 2005, 15:45 Saturday

While we're all gushing over the H1212 I think a couple of comments are in order.

Comment #1-Objectively, my tests don't statistically distinguish a winner between the H1212 and the RS28A. But remember, my tests are not the be all and end all of testing.

Comment #2-The RS28A has the more advanced motor and I'm sure I could find some tests to prove this... :W Perhaps this offsets the early QC issues of the RS28A.

All that to say that both are outstanding tweeters. There might be some audible differences between the two, but I doubt there is a clear winner.

I will look at the 1212 and an RS28A in more detail sometime down the road, when I get a chance, to see if I can ferret anything out.

As far as budget solutions, the 1212 wins because it's cheaper. Of course, the silver grill is a bit uglier than the RS28A.

**DearS** · 06 August 2005, 16:28 Saturday

zaphaudio.com has an MT using this tweeter, along with the L18 seas mid.

**DearS** · 08 August 2005, 12:58 Monday

So this tweeter can be dropped in to the Modula to make an aluminum set.

how does the RS180 stack up against the L18 in detail? like to see how it compares to the L18/seas MT in this area.

**JonMarsh** · 08 August 2005, 15:43 Monday

Why don't you try it and let us know?

Seriously, if both drivers are operating within their pistonic range, and midband distortion is similar, I suspect that for similar LF alignments they will sound, well, for want of a better word, similar.

Then, I guess it just comes down to which you think is cooler looking, or which you find more affordable- the RS180 seems to have a marked edge in the US in that regards, by about 35-40%. Still, I'd say, whichever floats your boat.

**DearS** · 08 August 2005, 16:06 Monday

thanks....they both are pretty interesting. although I would like to try them both, but there are many current DIY projects going around online to try.

**LNeilB** · 08 August 2005, 22:39 Monday

Great driver

The L18 is a complete winner. It costs a bit more, but you still get amazing performance out of it. For a few bucks more it might be worth a try. And Seas is known for consistency. My one concern with Dayton drivers is the history of production variations...

**DearS** · 09 August 2005, 00:02 Tuesday

thanks for the input.

Any negatives about the speakers you hear?

**capslock** · 09 August 2005, 06:59 Tuesday

Tdc, Tdfc

My personal opinion is that the TBC would tend to be even better than the TBFC. You can "upgrade" any TD(F)C to TB(F)C by buying the H9932 replacement voice coil. The motors are identical, according to Björn Magne of Seas.

The thing I don't like about the TBC is the diffusor (a thin piece of transparent plastic) underneath the grille. Anybody figured out how to remove the grille without doing damage?

And I tend to agree with Mark that it is likely that the RS28 has lower high order distortion, it having a doubly shielded motor and the Seas having no shielding whatsoever. The only thing that might make the Seas as good as it is is careful design of the pole piece geometry. It has a 1.8 T field in the gap, according to the datasheet. If this is true (usually those numbers are too optimistic), it operates its iron near saturation, which has much the same effect as a Faraday shield.

**JonMarsh** · 09 August 2005, 08:39 Tuesday

Originally posted by LNeilB

The L18 is a complete winner. It costs a bit more, but you still get amazing performance out of it. For a few bucks more it might be worth a try. And Seas is known for consistency. My one concern with Dayton drivers is the history of production variations...

I can understand your concerns, and I do think also that the L18 is good value for the money compared with most drivers available.

I haven't seen or heard of any consistency issues with the Dayton RS series woofers. Something to remember is that Darren sources the "Dayton" drivers from a lot of vendors, but specific models generally just from one source.

~Jon

**JoshK** · 09 August 2005, 12:16 Tuesday

Originally posted by capslock

Anybody figured out how to remove the grille without doing damage?

I too way interested in whether the Seas or the Dayton RS tweeter could have the grill removed for cosmetic reasons. Is it doing anything other than protection? Its for diffusion?

**tktran** · 09 August 2005, 12:40 Tuesday

Well, SEAS may have the consistency/reputation factor (perceived or real) but there's no denying that in terms of value for money, Parts Express really turned things upside down when they acquired the Reference Series drivers, and sold em to DIYers for peanuts. Imagine the cost price coming out of Taiwan!

The RS180 is a giant-slaying 7" incher in my book.
It tests and sounds almost as good, equal, or better than the top bunch, yet you can can buy FOUR, yes FOUR, for the price of a single ScanSpeak 18W8535/45 or SEAS W18E/EX001, and have enough money left over to cover the postage costs. Maybe TEN for the price of a single Accuton...

:

I'm not surprised that Parts Express doesn't carry SEAS, and has dropped the entire ScanSpeak line...

ops:

In http://206.13.113.199/ncdiyaudio/mar.../L18vRS180.htm
The L18 has very slight LD advantage, but the midrange NLD measures significantly better. Even if we couldn't decide if there's a clear winner- you can still buy TWO RS180 for the price of a single L18RNXP!

I'm a bit envious of you guys- If I was in the US, I'd buy and hoard a whole crate of these babies (it costs me more to ship than to buy any RS woofer, plus a 6-8 week wait without tracking via UPS Surface)...

**Mark K** · 09 August 2005, 15:48 Tuesday

I've not really seen any significant QC issues with the woofers and midwoofers. Some production variability in TS, but nothing unusual.

**jdybnis** · 09 August 2005, 20:11 Tuesday

Originally posted by capslock

My personal opinion is that the TBC would tend to be even better than the TBFC.

Can you elaborate on this. What is the difference without the ferofluid?

**capslock** · 10 August 2005, 07:25 Wednesday

well, just go back to Mark's test of TDC vs. TDFC

**Mark K** · 10 August 2005, 23:37 Wednesday

Originally posted by jdybnis

Can you elaborate on this. What is the difference without the ferofluid?

Well, the TDC seemed to have slightly better nonlinear distortion numbers. I emphasize the word slight so I still haven't made up my mind. It would be interesting to test the nonferro version of the tbfc/g...

**jdybnis** · 11 August 2005, 00:12 Thursday

It looks like the TDFC is more regular, for lack of a better word. There is that double impedence bump that the TDC has and another small irregularity higher up. I wonder if the back chamber on the TD(F)C is optimized for the TDFC and is sub-optimal without the ferro fluid. Maybe there is some resonance higher up supressed being supressed by the ferofluid too.

Anyways, can the TDC/TBC be crossed down as low as Jon's designs require?

**JonMarsh** · 11 August 2005, 07:37 Thursday

Originally posted by JoshK

I too way interested in whether the Seas or the Dayton RS tweeter could have the grill removed for cosmetic reasons. Is it doing anything other than protection? Its for diffusion?

This has been discussed before, and Dave's pages (DLR) show the "take down" steps for disassembly and removal of the original diffuser behind the grille in the RS28a. He then uses a felt diffuser on top of the grille.

Same process should be applicable to the Seas, IF the grille cover/front plate and VC assembly are seperate items- most likely the case.

~Jon

**LNeilB** · 11 August 2005, 09:04 Thursday

Should I?

Same process should be applicable to the Seas, IF the grille cover/front plate and VC assembly are seperate items- most likely the case.

~Jon[/QUOTE]

Do you recomend this tweak for the Seas Jon?

**JonMarsh** · 12 August 2005, 12:28 Friday

Yes. I've done it for virtually every hard dome tweeter I've ever used. I suggest listening without any diffuser, as well as with a felt donut diffuser like DLR made. Measuring doesn't hurt either, of course.

~Jon

**LNeilB** · 12 August 2005, 12:30 Friday

Help Me Understand

Originally posted by JonMarsh

Yes. I've done it for virtually every hard dome tweeter I've ever used. I suggest listening without any diffuser, as well as with a felt donut diffuser like DLR made. Measuring doesn't hurt either, of course.

~Jon

Measurements aside, what is the usual subjective difference, from the listening chair?

**JoshK** · 12 August 2005, 12:41 Friday

You know I did see/read the DLR pages but I don't see the diffusor in any of the pictures. Maybe I am just slow but am I missing something?

**TacoD** · 12 August 2005, 12:43 Friday

I think it is a transparant film behind the grill.

**JonMarsh** · 12 August 2005, 14:33 Friday

Taco's got it right- it's a plastic film behind the grille, shaped like a donut.

**capslock** · 12 August 2005, 16:48 Friday

Originally posted by JonMarsh

Same process should be applicable to the Seas, IF the grille cover/front plate and VC assembly are seperate items- most likely the case.

~Jon

Nope, I can tell because I have purchased spare TB(F)C VCs, in order to convert my TDFCs. Have a look at the pic in the Madisound online catalogue (H9932). You buy a new faceplate onto the back side of which is glued the surround. The front side has a groove into which the grille is glued. I now have a total of six Seas grille faceplates (4x TBC, 2x the new "22" model), and they seem to use varying amounts of glue, from a few beads to flooding the groove. Unless the glue is softened by either water or alcohol, only those with beads look like I might want to tackle them.

**JonMarsh** · 12 August 2005, 19:12 Friday

That's too bad. But, on the balance, we can probably live with it, especially still considering the price.

Besides, I've got a box full of RS28a's to play with...

**augerpro** · 27 November 2006, 02:38 Monday

Sorry for bringing this back to life but I'd like some clarity if I could. Considering how close the FF and non-FF versions of the TDC and TBC measure, would the main concern then center on power compression? I wonder if more stable performance is a better tradeoff to (mostly) less distortion displayed by the non-FF versions. Also, and I hesitate to ask this subjective question, does the FF affect "detail" at all?

One more question. So there is no way of removing the TBC's metal grid?

**augerpro** · 29 November 2006, 08:23 Wednesday

anyone?

**JonMarsh** · 29 November 2006, 10:34 Wednesday

I'd suggesting listening. Lower distortion in the non FF versions should give you some clues. I experimented a fair amount with FF back in the 90's, in the end decided not to retrofit drivers. In my opinion, FF is good if you want to extend power handling and durability under potentially abusive conditions, but for fidelity, just say no.

**Brian Bunge** · 29 November 2006, 15:14 Wednesday

Hey Jon! I sent you a PM a couple of days ago but have not heard back from you. Did you get it?