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bottleneck
05-23-2005, 05:51 AM
Hi!

Ive just sold my 8w 300B amp that I was using to drive a pair of valencias.

It clipped at loud volume.

Im thinking of going for an accuphase amp, and have the choice of going for something low power (like 20w p/ch - all class A), or higher power (like class A for 10w then another 150w class A/B).

Just wondered if anyone who has these speakers (or similar) could share their experiences on trying different amplifiers -

perhaps to suggest models that they thought were a good sonic match,

or to give advice on the amount of power these things really need to be powered properly.

NB
I dont really want valve amps again.

doodlebug
05-23-2005, 03:55 PM
I've driven my Valencias - all original except for upgraded caps in the crossover.

My favorite amp is the Harmon-Kardon Citation II tube amp. This does about 60wpc. It has been upgraded with Jim McShane (the HK guru, IMHO) caps and tubes. This amp drives them quite loudly in my office system and the meters on my Mac preamp, a C2200, tells me that they're not being driven that hard either.

I've also used a Mac MC-225 with similar results. Actually, I've got 2 of them and have also driven the Valencias with them strapped for monoblock operation.

One thing to consider is that with tube gear, you'll be able to adjust the impedance to best match your Valencias. Mine are 16 ohm drivers/crossover but I've found that they do sound difference on different taps.

I've got some 100wpc Hafler DH-220s that have been extensively modded but they do not do the horns in the Valencias justice. My old tube amps seem to work best.

Cheers,

David

Tom Loizeaux
05-23-2005, 04:41 PM
I drive mine with a B&K Mosfet power amp and they sound good, but I'm sure the Valencias sound great with class A tube amp!

Tom

speakerdave
05-23-2005, 06:44 PM
I listened to my 604's for years with the MC250 or the Citation II depending on mood, season and the maintenance requirements of the tube amp, but when I switched to the MC2200 second generation McIntosh solid state I found that the benefits of headroom were definitely audible even with very efficient speakers (101 dB, 1 watt at 1 meter), especially on those occasions when you really want to just crank it. The vast majority of my listening was done at lower volumes (my neighbors are grateful) and the 6550 push pull was plenty of amp, certainly better than the 50 watt solid state A/B; an EL34 or even a 6BQ5 would probably have been OK. But I speak of old designs, and there are probably a lot of amps of all types in all power ranges out there now that would beat any of the ones I'm familiar with. (I don't want to know about them.) I know you are perfectly aware of the trade offs when giving up the 300B, and I would think a Class A solid state amp of about 25 watts would be the logical thing to try. But I think the benefits of class A amps are realized at low power. I don't know if they are any better when overdriven. Ian will probably speak to that.

David

Mr. Widget
05-23-2005, 09:57 PM
Im thinking of going for an accuphase amp, and have the choice of going for something low power (like 20w p/ch - all class A), or higher power (like class A for 10w then another 150w class A/B).

If 8 watts didn't cut it then you probably need to go to 80 watts for an appreciable change. The type, brand etc. is a personal choice thing, but don't consider getting a really great 25 watt amp as that is only about 4db of additional headroom and if you are in need of more power I would recommend getting at least 10dB of additional headroom if not even more!

Widget

bottleneck
05-24-2005, 12:14 PM
Thats interesting.

Traditional logic (elsewhere) says that high efficiency speakers can be paired with SET amps, and in fact I thought it would be a good match.

It seems that maybe the bass units on the valencias like to see more current (is that why they clip?).

Interesting that 25w+ seems to be reccomended, and many people are using 80w+ with high efficiency speakers.

It looks like the sensitivity figures arent the yardstick I thought they were!.

Perhaps the bigger integrated which is 180w p/ch is the safer bet, despite it not being class A.

Thanks
Chris

Mr. Widget
05-24-2005, 12:32 PM
A 2.5 watt SET may be enough for one person and not for another. If you want playback at realistic SPLs for rock, you will need more power than someone who listens to chamber music at 80dB...

Widget

Robh3606
05-24-2005, 01:28 PM
"Traditional logic (elsewhere) says that high efficiency speakers can be paired with SET amps, and in fact I thought it would be a good match."

I think it's a common misconception and if your not careful you can underpower them. You still need decent power reserves and even at over 100Db sensitivity once you factor in your distance from the speakers, where you will loose at least 6dB, the headroom your were counting on is simply gone. I agree with Widget always try to have at least 10dB over average with the listening distance factored in. Ideal is at least 20dB for reproduction at realistic levels if that's your cup of tea.

Rob:)

louped garouv
05-24-2005, 01:45 PM
I have been running with about 250WPC (EV 7300a) with my 19s for the past few months.... dramatic improvement over the 14WPC 6BQ5 tube amp I had been running them with before.......


the 19s did sound acceptable for folk/jazz/blues on the tubes, but the bass would sound real muddy (like it couldn't keep up) when playing modern dance music..... with the EV the 19s got really fast (good transients) -- guess they just wanted more power.......

prcinka
01-20-2008, 04:06 PM
yes, I am using Mactone 40w a channel with the Altec Santiago and it is great.....better then my previous 13w a channel Shindo....some people say the Santiago is not very "high" efficient, but the horn is the same as the Valencia, just the woofer is sealed unit. I did upgraded all the parts in the Santiago's, though....drivers been re-done and crossovers updated with close tolerance parts....

Zilch
01-22-2008, 10:45 PM
You're missing out on what I consider the best option: Biamp.

For less than $150 you can set up with an active analog crossover and run your horns on wimpy tubes and the bass on SS.

You'll also be able to try CD compensation on the HF (Valencias and Santiagos need it,) and delay on the woofer (they need that, too).

Behringer CX3400 was on sale at Guitar Center for $99 recently. Tell them you want that price.... :yes:

SMKSoundPro
01-22-2008, 11:23 PM
I agree.

After all of the stuff that everyone added to the Valencia thread, and if I still had them in my kit, I would have biamped them!

(I have not been to the pawn shops, lately. Probably time to make the rounds and see if he dumped them yet for a score of drugs.)

I have a Rane AC22 crossover with delay on it that would have perfect!

I guess I am glad they're gone. Know I don't have to think about trying biamping!

Give it a try and let us know what you think.

Scotty.

diamondsouled
01-25-2008, 02:04 AM
I'm running my Valencias on VAS Citation Sound mono blocks with the New Sensor KT88 Gold Lion remake tubes. They sound awesome.

I also have some JBL UHF 2404s hooked up with the Valencias which makes quite a difference.

Many people don't realize that to double your db you need to increase your power by a factor of 10. Thus to double the sound of your 8W amp you'd need to go with a 80W amp. This is where SET amps just don't have the juice even with an efficient speaker like the Valencia.

I've used a Nad SS amp on my Valencias as well and it sounded quite good.

Lar

jblnut
01-28-2008, 07:38 PM
I believe the correct formula is that to increase the sound level 3db (which is perceived as "doubling") you need 2x the power, not 10x.

jblnut



I'm running my Valencias on VAS Citation Sound mono blocks with the New Sensor KT88 Gold Lion remake tubes. They sound awesome.

I also have some JBL UHF 2404s hooked up with the Valencias which makes quite a difference.

Many people don't realize that to double your db you need to increase your power by a factor of 10. Thus to double the sound of your 8W amp you'd need to go with a 80W amp. This is where SET amps just don't have the juice even with an efficient speaker like the Valencia.

I've used a Nad SS amp on my Valencias as well and it sounded quite good.

Lar

Mr. Widget
01-28-2008, 09:57 PM
I believe the correct formula is that to increase the sound level 3db (which is perceived as "doubling")... :no:

Perceived doubling is 10dB... at least that is what the experts say... personally I think it is another of those subjective things about audio...

The idea is that 1 dB is the smallest increase in wide band noise that an average listener can perceive... and 10 of these units (10dB) is perceived as "twice as loud". 3dB however is clearly audible but not really twice as loud sounding but is twice the power and 10dB is ten times the power. Therefore to reach a level that is perceived as being twice as loud, whatever that means, does indeed require ten times the watts.


Widget

diamondsouled
02-01-2008, 01:14 PM
:no:

Perceived doubling is 10dB... at least that is what the experts say... personally I think it is another of those subjective things about audio...

The idea is that 1 dB is the smallest increase in wide band noise that an average listener can perceive... and 10 of these units (10dB) is perceived as "twice as loud". 3dB however is clearly audible but not really twice as loud sounding but is twice the power and 10dB is ten times the power. Therefore to reach a level that is perceived as being twice as loud, whatever that means, does indeed require ten times the watts.


Widget

Thanks for the explanation Widg. It is a pretty subjective thing as you point out though.

It is cold here by anyones definition though. It has warmed up to -49 F from a cold of -58 F this morning.

It is so cold out that my farts have a wind chill factor. It is 49 below but they smell like it's 70 below!:p

Lar

Ian Mackenzie
02-01-2008, 03:21 PM
Save them for internal heating. If you dont blow the bottom out of your world you may blow the world out of your bottom.

Some of these small valve amsp tend to soft clip so they sound more powerful than they should.

I will go with 6 db more power to benefit from any useful headroom over 8 watts ie 32 watts.

spwal
02-16-2008, 07:15 AM
how come noe one has suggested keeping the 8 wpc and biamping with an inexpensive external active 2 way and SS amp?

Nipper
01-31-2009, 09:25 PM
Hi!

Ive just sold my 8w 300B amp that I was using to drive a pair of valencias.

It clipped at loud volume.

Im thinking of going for an accuphase amp, and have the choice of going for something low power (like 20w p/ch - all class A), or higher power (like class A for 10w then another 150w class A/B).

Just wondered if anyone who has these speakers (or similar) could share their experiences on trying different amplifiers -

perhaps to suggest models that they thought were a good sonic match,

or to give advice on the amount of power these things really need to be powered properly.

NB
I dont really want valve amps again.

If there is any way possible, try a Sansui AU-9500 with your Valencias.
You will remember me. ;)

Triumph Don
02-02-2009, 01:37 PM
As his post was almost 4 years ago, I'm sure he already got an amp. Wonder if he even still has the Valencias?

Nipper
02-02-2009, 09:01 PM
As his post was almost 4 years ago, I'm sure he already got an amp. Wonder if he even still has the Valencias?

Others searching on the thread subject may benefit some day. :)

bigstereo
03-24-2009, 02:49 PM
Others searching on the thread subject may benefit some day. :)

QFT. I just acquired a pair of Altec 848A and will power with a McIntosh MC2300. 300wpc. That oughta be about right.:D

RJ