8-ohm DIY high sensitivity speakers for 300B tube needed

Jump to Latest
P

Pegasus123

Member
Joined 2014
#1
The 300B tube amplifiers that I want only have a single 8 ohm tap. I find it to be quite a chore trying to find a high sensitivity 8-ohm speaker.

So far I have looked at Klipschorns (used), pi speakers kits, and diysoundgroup Titan 615 (no longer sold?)

Are there any other designs I am missing with at least 95db sensitivity at 8 ohms?
 
#3
My two speakers which I already own are:
91-92 db with a 5-6 ohm impedance, too insensitive
96db with six ohms up to 200hz, 4 ohms from 200hz-3,000hz, and six ohms above that.

While this is not the tube amp I will be using this picture attached shows the impact of using a 8 ohm speaker on a four ohm tap. I'm a little concerned that I will quickly eat the 300b's and not get the full SET experience with a four ohm load.

20hz-20khz on an 8 ohm tap. 8 ohm is red and blue. 4 ohm is cyan and magenta.
119ATM300fig09.jpg

On the other hand at 1khz on an eight ohm tap:
100mW=.12%, 1W=.4%, 5W=1.4% distortion

1khz with a 4 ohm load on an eight ohm tap:
100mW=.25%, 1W=.8%, 5W=4% distortion
 
#4
You could build an Altec clone, like a 620 cabinet with a GPA 604E-II or 604-8H-III coaxial driver. That will be very expensive altough as those drivers and the filter for it are very expensive. And original Altec 604's are even more expensive. the drivers are 98dB sensitive.

A much cheaper option is a fullrange cabinet with an Fane Sovereighn 12-250TC (98dB sensitivity). This is a pro audio mid-top driver but on low power (<15w) it works great as a fullrange driver. 80L sealed works great if you don't need to much bass. A very big (300L) ported should also work and would easely hit an F3 of 30Hz , but again on low power.
 
Last edited:
#5
Thank you waxx. I am looking for something more like a kit or a speaker well detailed plans and foolproof.

@ multitask. I have seen Crites's site before for upgrades to Klipsch La Scalas & K-horns. For the speaker you linked how are they when it comes to horn-honk? The Seos waveguides were the first I have heard that didn't sound shouty.
 
#8
Pegasus123 said:
@ multitask. I have seen Crites's site before for upgrades to Klipsch La Scalas & K-horns. For the speaker you linked how are they when it comes to horn-honk? The Seos waveguides were the first I have heard that didn't sound shouty.
Click to expand...
they do have the 2380 horn which some attribute to horn coloration. i did not find them harsh in any way in my demo though (style A). big mids and lots of bass. (i would not expect them to dig very low in freq).
the tweeter driver/crossover isnt that great in the high-end.
 
You must log in or register to reply here.
Top Bottom