Sensitive bookshelf speakers for Tripath

[kiteohoi]

I am making a tripath amplifier, and I would like to build a pair of bookshelf speakers for them.

I understand that they need to be sensitive, and I have googled around a bit without really luck.

Does anyone have a good recommendation for elements and drawings (In the £100+ range)?

These are the specs for the amp:

• Class-T architecture
• Single Supply Operation
• Audiophile Quality Sound
• 0.03% THD+N @ 10W 4Ohm
• 0.1% THD+N @12W 4Ohm
• 0.18% IHF-IM @ 1W 4Ohm
• High Power
• 13W @ 8 Ohms, 10% THD+N
• 23W @ 4 Ohms10% THD+N
• 38W EIAJ* VDD=14.4V @ 4Ohm
• High Efficiency
• 88% @ 12W 8Ohm
• 81% @ 20W 4Ohm
• Dynamic Range = 103 dB
• Up to 2X25Wrms @ 4Ohm, VDD=14.6V
• Mute and Sleep inputs
• Turn-on & turn-off pop suppression
• Over-current protection

Thanks

[ssportclay]

Originally Posted by kiteohoi

I am making a tripath amplifier, and I would like to build a pair of bookshelf speakers for them.

I understand that they need to be sensitive, and I have googled around a bit without really luck.

Does anyone have a good recommendation for elements and drawings (In the £100+ range)?

These are the specs for the amp:

• Class-T architecture
• Single Supply Operation
• Audiophile Quality Sound
• 0.03% THD+N @ 10W 4Ohm
• 0.1% THD+N @12W 4Ohm
• 0.18% IHF-IM @ 1W 4Ohm
• High Power
• 13W @ 8 Ohms, 10% THD+N
• 23W @ 4 Ohms10% THD+N
• 38W EIAJ* VDD=14.4V @ 4Ohm
• High Efficiency
• 88% @ 12W 8Ohm
• 81% @ 20W 4Ohm
• Dynamic Range = 103 dB
• Up to 2X25Wrms @ 4Ohm, VDD=14.6V
• Mute and Sleep inputs
• Turn-on & turn-off pop suppression
• Over-current protection

Thanks

If you are looking for the most efficiency, a back loaded horn based on the Fostex FE126En or FE166En would be about the best you could do. One of the Fonken bookshelves would also work but you would some efficiency.

[planet10]

As Mr Clay says.

Of the drivers i am familiar with, FF125wk, FF165wk would be the most efficient in a bookshelf size, the former may be the only one that does not exceed your budget.

5-9 litre reflex would be good. My boxes for these are under development or in beta.

dave

[kiteohoi]

Thanks guys. I will have a look!

[KyleinCowichan]

I have been running some CHR-70 and EL70 based speakers on a Dayton dta-2 amp, 15wpc tripath and it handles them very well. Lots of power in a decently sized living room. I barely make it past 3oclock on the volume knob with input from my airport express (it's a little hotter than straight from my iPod) and they get loud.

[kiteohoi]

I passed by a DIY speaker shop today here in Holland, and they claimed that you cannot make small/bookshelf speakers with high sensitivity for a tripath amp, because there will be no bass...

Now, that can be a fact or just their opinion. What are your experiences?

[KyleinCowichan]

I had some CHR-70s in some planet 10 enclosures and the bass was most certainly present. I used the DTA-2 amp mention above, definitely on the cheap side of ta2024 amps. I am about to buy a TA2020 based amp to replace the DTA-2 (sister finally got to take it home). Some people in for forum have said the 2020 has better bass but to 2024 has better detail.

http://homepage.mac.com/tlinespeaker...703-300611.pdf

The enclosure I was using is linked above.

KM

[planet10]

Originally Posted by kiteohoi

I passed by a DIY speaker shop today here in Holland, and they claimed that you cannot make small/bookshelf speakers with high sensitivity for a tripath amp, because there will be no bass...

Now, that can be a fact or just their opinion. What are your experiences?

You do have both hoffmann's iron law, and the fact that, given there is an Sd term in the efficiency, a small driver in a small box will be challenged to be efficient and have deep bass. Something has to give.

And any small driver will be limited as far as dynamics in the bass are concerned

EL70 in 13 litre box (Mar-Kel70) can produce midboggling bass (given its size). Put it in a 4.5 liter box (mMar-Kel) and it still produces some bass (but you get the feeling the driver is being held back), but somehwere around 85 dB/1w (the 4 ohm impedance gives it a 3dB advantage with T-amps over the other usual candidates).

In the "same" box, the FE127e in the mFonken is ~90 dB, will produce less bass (but it sounds less constrained and perhaps has a bit better balance). With the same driver in the 13 litre Fonken some claim bass into the 40s in room,i estimate mine, in my room more like into the low 60s)

dave

[BHTX]

Might want to consider a 4 ohm driver for that amp.
I can't really think of a sensitive one off the top of my head.
Just a thought.

[stoc005]

4 ohms is a good idea and you might find some 6 ohm specimens if you look hard.
Try this:High Efficiency Speakers. His search for high efficiency speakers. His designs are very good.