I was planning to pick up a Inspire EL84 amplifier to power my B&W 640i.
My room is relatively small but I like to listen to music pretty loud. I also watch movies with these. Right now they are hooked up to a cheap 20 watt tripath amplifier. The speakers are rated at 4 ohm nominal Impendance and 91db spl(2.83V 1m).
Would the 5 watt Inspire EL84 satisfy my needs?
My room is relatively small but I like to listen to music pretty loud. I also watch movies with these. Right now they are hooked up to a cheap 20 watt tripath amplifier. The speakers are rated at 4 ohm nominal Impendance and 91db spl(2.83V 1m).
Would the 5 watt Inspire EL84 satisfy my needs?
Five watts can be louder than you think.
Try this to get an idea,
http://www.diyaudio.com/forums/mult...much-voltage-power-do-your-speakers-need.html
Try this to get an idea,
http://www.diyaudio.com/forums/mult...much-voltage-power-do-your-speakers-need.html
Your speaker specs is a bit odd. 2,83 V to 4 ohms is 2 watts.
Isn't the the sensitivity usually specified at 1 watt ?
5 watts produce 4 dB more sound pressure than 2 watts, i.e. 95 dB spl.
I'm picking the speaker has a pretty vertiginous impedance curve that would decimate any hope of an EL84 amp providing reasonable drive.
Power may not be a problem - impedance match will be.
Power may not be a problem - impedance match will be.
Ripped right out of the B&W website. DM640i
46Hz – 20kHz ± 2dB on reference axis
91dB spl(2.83V 1m)
4 ohms
30W – 200W into 4 ohms on
undistorted speech and music
programme
IMO/IME it is highly unlikely that a 5 WPC tube amp will prove satisfactory, when mated to the B&W speakers. The "true" sensitivity of the speakers is 88 dB., as 2.83 V. into 4 ohms is 2 W., not 1 W. 😡 Paul Joppa's 102 dB. rule suggests you need a minimum of 32 WPC.
I would not mate the B&W speakers to tubed power amplification, except for a Harman/Kardon Citation II, which (for a tube amp) has a gargantuan damping factor. The "Deuce" works very well with AR-3s and AR-9s, which (I suspect) have much in common with the B&Ws.
Then the sensitivity of your speaker is 3 dB less than a 8 ohms speker with 91dB spl (at 2.83V 1m), but this may not be any problem.
SE EL84 will give You 4-5 Wt with distortions. For Your 90 dB speakers is suitable PP EL84 /12 Wt/ or more cheep PP ECL /PCL/82 or 86 /8-10 Wt/, only two tubes per channel, instead 3 or 4 tubes per ch. in PP EL84. You can find the treads with schematics on the forum. I'd like advice You.
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PHILIPS H4F 74 A/01 / ECL82 / 6BM8
"En sa Fonction PP delivrant 10 Wt" - this schematic. You can add input poti 50-100kohm. PS is next schem.
"En sa Fonction PP delivrant 10 Wt" - this schematic. You can add input poti 50-100kohm. PS is next schem.
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I recently built a direct-coupled SE 2A3 amp, about 3W per channel. Barely loud enough for me on ~96dB speakers.
You might want to re-think your decision if you like your music loud.
You might want to re-think your decision if you like your music loud.
I had a Pass AmpCampAmp with 5 Watt perCh. with my 92db/8Ohm Speaker.
In this constellation it was perfect for normal listening.
But if i want to listen louder with this amp, the bass becomes weaker and the music dosn`t have so much attack.
So i always took the bigger amp for louder listening.
In this constellation it was perfect for normal listening.
But if i want to listen louder with this amp, the bass becomes weaker and the music dosn`t have so much attack.
So i always took the bigger amp for louder listening.
Thanks guys for your input!
I guess I will be getting a PS Audio HCA 2 instead.
I might build a pair of monoblock gainclones later!
I guess I will be getting a PS Audio HCA 2 instead.
I might build a pair of monoblock gainclones later!
More than 1 GOOD sounding rig has been put together with a nice tube preamp driving a quality SS power amp.
System synergy is the name of the game. Match the power amp and speakers very carefully.
I do not think you will have enough power from EL84 SE for your speakers. Even for acoustic type of music you need 15-20W with them. I use 15W amp with 845 tubes driving B&W802D, and it is barely adequate for small scale music. For anything else I have Bryston with 300W on each side - speaker switch rules.
B&W speakers are generally bad for tube amplifiers. A good chuck of power is wasted because of their highly reactive load (not converted into sound).....regardless of their claimed sensitivity (or effective efficiency) they are anything but the ideal load for tube amps.
Seems that not all B&W speakers fail with tube amps... I have adequately driven (for me, in my listening room) B&W 705 with a 1W tube amp. But, I do listen rather quietly, I suppose...
Yes, you are right. Some bookshelf types might not be bad except their effective impedance being some 5-6 ohm rather than 8. Mainly the bad ones are the tower speakers, especially those with 2 woofers....
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