2 way design around Seas 27TFFC

Jump to Latest
P

peterpaan89

Member
Joined 2020
#1
Dear DIYers,
I have the desire to build my first speaker and have some Seas 27TFFC lying around. I didn't find many DIY projects with this tweeter (some Troels) and was wondering if anyone can recommend something or has an idea:

  • 2 way standmount
  • up to 300 Euros for woofers and xover

Happy for any feedback or advice!

Johannes
 
#3
 
Last edited:
  • Like
Reactions: peterpaan89
#6
Thank you for all of your suggestions! My problem is that I have not the slightest idea (as always in DIY) what the speaker will sound like in the end. My goal is a speaker that is not too revealing and will play all kinds of music well, not only audiophile recordings. Is any of these you named known for this quality? Attributes I am looking for are engaging (makes me want to dance), warm (very sensitive to harshness in the treble) and easy for long listening sessions. I know it's all the clichés at once but that is at least my goal.
 
#7
Yes this indeed is the problem. To me it is how will this speaker sound in my living room. I seem to enjoy speakers that mimic the Harmon house curve which has the response decreasing as the frequency increases. These designs have about a 5dB difference from low to high. In the design i linked to the second crossover would be more to my liking, but it is diy and the padding resistors can still be changed to please your ear. What a design does is integrate the drivers well.
 
#8

Attachments

  • 2 ways.jpg
    2 ways.jpg
    341.6 KB · Views: 66
#10
I used the Seas 27TFFC tweeters and a Silver Flute 6 1/2 inch 8 ohm drivers years ago and made a two way for my dad.
I did a rear ported box. It’s floor standing with sealed stand chambers on the top and bottom of the cabinet. It’s really heavy for this small floor standing speakers. They still are playing sound after 14 years of kid abuse. Little fingers are a monster to control. No grills on them. The drivers were routed flush mount close to each other. Crossover is at 2,700 hz? I can’t remember what place I did the crossover at. I used all caps and no air coils. Eric from parts express designed the crossovers and box for me so you know these are special to me. Jeff
 
#11
peterpaan89 said:
My problem is that I have not the slightest idea (as always in DIY) what the speaker will sound like in the end. My goal is a speaker that is not too revealing and will play all kinds of music well, not only audiophile recordings.
Click to expand...
This is an issue with any speaker, be it retail or DIY; it's a very rare store in Oz which will let you borrow a speaker to see how it sounds in your room.

The best suggestion is to find a design which has been widely and well reviewed, such as the Tritrix or Classix II (only mention these as I've built them based on those criteria). Usually, the DIY designer's write up will say something about the speakers' character or 'voicing' and sound level output.

If you didn't have the SEAS I'd suggest something like the Classix II or 2.5 which would fit your listening requirements.

It will need some google translating, but you could search for reviews about the designs in Post 3 and see how you go.

Here's an extract from the write up for the Dutch design with the Peerless 830657, done with Google translate

"Floorstand - aka LBVS

A homegrown classic from home

The self-built loudspeaker also has its classics. The Rogers Monitor, the Needle, the Reference Monitor, the Hatt, just to name a few. Recently a design has been added that is fast becoming such a classic: the Low Budget 2-way Floorstander (also affectionately called the LBVS) designed by Edo van der Laarse. This design combines a set of low priced parts into a high quality speaker.

By slightly adjusting the values of the tweeter's “L pad” resistances, the treble can be adjusted to suit personal taste and listening space. A relatively small change can already have a clearly audible effect here

Conclusion

Everyone who has been allowed to listen to this speaker will agree: a good speaker does not have to be expensive. With this design, Edo van der Laarse has made a clear statement in the budget class that many self-builders who preceded us already enjoy it, and I am sure that many more self-builders will follow who will be proud and satisfied with their self-built LBVS ."

The web page has full build details, but unfortunately doesn't talk about the 'character' of the sound; but you might find some reviews on line or on a Forum.

Geoff
 
Last edited:
  • Like
Reactions: peterpaan89
#12
Peerless 830657- different boxes (in German ?)
Use the edos filter seas 27tff & 830657 &-

http://web.archive.org/web/20090320034817/http://www.vifa.de/bausatz/starter/kit1/SAKdocu.pdf

Tower
http://web.archive.org/web/20130514033207/http://www.vifa.de/bausatz/starter/kit2/BVSAK2S.pdf

Bookshelf
http://web.archive.org/web/20111005072529/http://www.vifa.de/bausatz/starter/kit1/BVSAK1R.pdf

and Edos LBVS MLTL
https://zelfbouwaudio.nl/forum/viewtopic.php?f=59&t=15285

Parts Express
https://www.parts-express.com/Peerless-830657-6-1-2-Paper-Cone-SDS-Woofer-264-1088

�

Optimum Cabinet Size (determined using BassBox 6 Pro High Fidelity suggestion)​

Sealed Volume0.4ft³
Sealed F389Hz
Vented Volume1.27ft³
Vented F345Hz
 
Last edited:
#13
Don't get fooled by the (relative) low price, the Seas is a very good tweeter that you can use in commercial constructions with a 10.000$ price tag. If you find some DIYS kit that uses it, it should be something you will be happy to own and listen to.

So if you do not know how to do the x-over, better don't try. Even the best speaker components can only be as good as the construction of x-over and cabinet allow. Changing a driver or modifying the box will always need another frequency divider network. There are no two interchangeable speaker chassis from different brands on the market.
Follow instructions and do not get creative in changing components. That is a rule for any quality loudspeaker kit you will build.

If you have a lot of experience, you can design a new speaker around this tweeter. There are easily a hundred mid bass units that will work, but any one with a very different x-over and cabinet construction.
 
  • Like
Reactions: peterpaan89
#14
Thank you for all of your suggestions. I should have written in the topic that a floorstander is not an option. Also have made some bad experiences using a similar driver for a build and in the end I lost a lot of money, so I won't be doing that again. 27TDFC seems to be the same but it isn't, otherwise it would say so. I don't want to f*** around with xover tuning problems anymore. It does not seem as if there is such a project out there, at least none of the above meet my requirements: proper build plans, 2 way stand mount, x-over for woofer + 27tffc. Thank you anyways for all your effort.

Cheers
 
#15
peterpaan89 said:
Attributes I am looking for are engaging (makes me want to dance), warm (very sensitive to harshness in the treble) and easy for long listening sessions. I know it's all the clichés at once but that is at least my goal.
Click to expand...
'Toe tapping' speakers were my primary DIY 'career' and it's about non audiophile (billiard table flat) frequency response, so in theory basically any speaker can be EQ'd to be one, though historically an 800 Hz/2nd XO two way horn/woofer was the first TTBOMK and most popular to date.

Measured response of the original
 
#16
Have you seen this project? The cabinet's made from granite (!) but you could make it from wood; stand mount size, uses your tweeter:

https://diyaudioprojects.com/Speakers/Seas-Granite-Speakers/

Stated specs;
External box dimensions 240 x 350 x 280 mm. Internal box dimensions 200 x 310 x 240 mm. Box material 20 mm thick black granite (Nero Assoluto). Weight 35 kg. Enclosure volume 14.9 L. Bass reflex enclosure tuned to 45 Hz. Port length 160 mm
Input power 80W. Sensitivity 87.5 dB. Transmission bandwidth 40Hz - 20kHz. Impedance 6 ohm.

Geoff
 
  • Like
Reactions: peterpaan89
#19
Thanks Geoff. I'm not going with anything similar anymore. Either the drivers are available or I choose a different design. No need for doing the same mistake twice and building a whole speaker and in the end not being satisfied with the result as something is just a tiny little bit off. But thank you for your efforts🙂
 
You must log in or register to reply here.
Top Bottom