Valve amp for speakers - enough power?

[philv]

Hi

I have some kef 104/4 speakers.
Sensitivity 92 db into 4 ohms.
So after adjustment this is equivant to 89 into 8 ohms.
So a comparative sensitivit of 89 db.
They are rated for amplifiers between 25 and 200 watts per channel.


I habe bought but not receved yet an audio innovations 700 valve amplifier.
Now this is rated as follows -

5.5 w - 20 hz
23.5 w. - 1 khz
6.5 w. - 20 khz
Figures are the same more or less for 4 and 8 ohms.

Am i going to have problems?

I dont play music loud - jazz, not rock.

I think the speakers are reasonably efficient?

Should the power at just under 25 woc be ok?

Thanks

[Pupp]

It'll be fine

Great thing about valve amps is you can drive them hard without them decending into any horrible harmful clipping (and I doubt you'll drive it anything like hard enough to worry it). Connect up, sit back, enjoy...

[NDA]

The 700 is Class A isn't it?

Should be perfect and lovely for jazz.....

[philv]

And the kefs are gorgeous for it aswell.

It's like waiting for christmas morning - waiting for the amp to arrive in the post!

[NDA]

What sort of Jazz?

Chick Corea kind of jazz? Steely Dan kind? Coleman Hawkins type?

[0a]

I'm using a less powerful valve amp at the moment for harder to drive speakers, I was surprised how good it sounds!

[philv]

To be honest -iistening to all sorts at the moment.

Haven't realy listened to much in the past so i'm experimenting.

I'm open to suggestions if you have reccomendations that HAVE to be listed to.

Cheers

[NDA]

Well I guess there'll be a thousand recommendations along any minute now..... But from a fellow audiophile and jazz/music fan I'd try this little selection!

Steely Dan - Aja

John Abercrombie - Current Events

Keith Jarrett - The Koln Concert

Jeff Beck - Live at Ronnie Scott's

Gregory Porter - Illusion

Donald Fagen - The Nightfly

Miles Davies - Kind of Blue




That should keep you going and would be an interesting spread of styles.

[philv]

Much appreciated.

I'll look into thoses tomorrow.

Thanks

[Pupp]

Take Five - Dave Brubeck
The Sidewinder - Lee Morgan

Both will make it breathe

[telecat]

I use a Series 500 into Impulse Lali Speakers which are rated at 89db into 8ohm. It gets a bit loud Beyond 25% of the volume/gain so I shouldn't worry about it. The S500 has three Pairs of Speaker Outputs. 4OHM 8OHM and 12OHM and I expect the S700 should be similar. I use the 8OHM with no problems. One thing that you can look at is uprating the valves. All mine are Mullard types but some find them a little "soft". I'd look around the forums to see what's popular. Last thing is that many replace the EL34 power valves with 5881's. It's due to the EL34's damaging Amps when they "blow". More info and some interesting advice can be gleaned from Border Patrol's Website.

Edited by telecat on Monday 6th February 14:12

[philv]

Thanks for the replies.

Might seem like a silly question - but how are the valves removed/inserted?
Do they just push in / out?

I thought i should check they are inserted correctly before using for the first time.

I did say i was a novice with valve amplifiers!


Oh and did you make any upgrades to the 500?
are they worth doing?

Thanks

[Speedracer329]

philv said:

Thanks for the replies.

Might seem like a silly question - but how are the valves removed/inserted?
Do they just push in / out?

I thought i should check they are inserted correctly before using for the first time.

I did say i was a novice with valve amplifiers!


Oh and did you make any upgrades to the 500?
are they worth doing?

Thanks

Yes, just pull them out, & push them in. Make sure when you push them in that you have the pins at the bottom aligned correctly to the holes on the base unit.

[philv]

Thanks.

[thesyn]

Valve power amps always seem to produce "stronger" watts in output than solid state!

[telecat]

The Power valves have a "Bump" that aligns with a recess on the socket. The Pre, (little) valves have pins that will align with the holes in the socket. They do just pull out and push in. Don't do it unless the amp has been switched off for at least 5 minutes and I always use a clean cloth or glove so as not to leave finger marks on the Glass envelope. The sound changes depending on the valves used. I also found that some valves last longer than others and that some are really inferior to others. Sylvania/Philips ECC82's caused me problems. As for upgrades if you do find the "bug" hits you talk to Border Patrol. The ultimate upgrade is their PSU which is £1000. Most people love it but I have heard some thought it changed the sound too much. One last tip. The amp needs to warm up. I find it is at it's best after an hour but is pretty close after 15 minutes.