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ooppalla
09-27-2004, 05:15 PM
I am running a pair 4425s I just bought from Ebay with my Yamaha 850 receiver, 80 RMS.
The sound is a whole new demension of Quality, brings me back to my recording studio days of the 70s, but they seem a little harsh in the upper mid ranges.
I have an opportunity to buy from the same seller a Hafler P-3000 (150 rms) or a QSC USA900 (225 or so rms)
They have more power, but I do not think power is the issue as the speakers are in the bedroom and I don't listen much above 90-95 DBs
Do either of these amps have anything special? Are expensive Tube amps the answer, any suggestions?
Is there an amp that I should look for that best matches the 4425s?
Thank you for your input

dancing-dave
09-27-2004, 05:40 PM
My first instinct is to suggest the Yamaha P2200. They are used widely in studios for main monitors and may work to bring the most of your new speakers.

still4given
09-28-2004, 08:35 AM
I'm pretty new to my 4425's but I'm running them with a Hafler DH200 and I think they sound great! I'm using a Bryston .4B preamp and a Denon CD player. These things have some serious bass kick, but in my room I have the L-pads turned pretty low.

Blessings, Terry

Tweak48
10-01-2004, 08:28 PM
4425s are extremely revealing near field monitors, and not the most efficient (91db). They sound great with my VTL ST-85 tube amp (EL-34s push-pull at 85 watts @ 1kHz), unless pushed real hard. If you're pushing a s/s amp which is rated at about the same power, it's no wonder that things are getting a little nasty. Tube amps tend to degrade more gracefully when pushed into overload.

Actually, my 4425s sound better with my solid state 125 watt Conrad Johnson, with greater headroom, and is more laid back; to the point where it requires bringing the mid-tweet levels up a bit. The VTL is actually brighter than the s/s amp. The ConnieJay is half the price of the VTL.

I believe your solution is a high quality s/s amplifer with sufficient headroom to keep the 4425s out of touble.

Good luck.

Bryan

Robh3606
10-01-2004, 08:34 PM
Hey could you tell the dog to turn his high beams down!

Rob:)

Nice looking room and dog!

ooppalla
10-01-2004, 09:37 PM
Sure the dog is smiling he is in a beautiful room surrounded by 4425s, powered by Conrad Johnson... :bouncy:
Great input... I think I need some more time playing with the L pads with lots of different sources ... what amazes me is that when I was a lad I was told power amps were all the same (specks taken into account of course) ... and hard clipping Crowns ruled the studios ... later I learned about 2nd and third harmonic distortion so I understand the tube thing, and now with the 4425s I am hearing everything.
Bryan is right on the money when he wrote,
"4425s are extremely revealing near field monitors"
So I may infact be pushed to the last thing I thought I would need... a pricey amp. Great input, More please :p

Zilch
10-01-2004, 10:11 PM
Naw. 6230 or 6260. Both under $200 on eBay nowadays.... :-)

Robh3606
10-02-2004, 10:49 AM
Well not really E-Bay can get you some bargains. I use Crown PS-200's' Nice amps and they can be had for very little money. Just watch the Pro Section they come up often enough. Get a pair and strap them you will have plenty of power.

Rob:)

Ken Pachkowsky
10-02-2004, 01:28 PM
May I suggest if the space is large enough, that the left speaker be put on the other side of the hearth and pointed in the same general direction as the right?

This would have a very positive effect on the imaging of your system. The soundstage would much deeper as well.

Just a thought.

Ken

Tweak48
10-02-2004, 04:26 PM
Good suggestion, Ken. It certainly would be easy enough to try, as the cable comes right out of the lower corner of the cabinet. I wondered about placing it there, but always dismissed it because I didn't think I would get enough channel separation with the speakers only about 6 feet apart.

I must admit the imaging is not great with the current setup, but with the 4425's dispersion of 100X100 degrees, the sound stage is pretty good. It's actually a rather large room, "L" shaped with an eating area, opening to a kitchen via a cooking island, so there is a lot of acoustic space to fill.

I'll give it a try and report back.

Ken Pachkowsky
10-02-2004, 04:41 PM
Maybe the speakers would go on either side of the fireplace?

I have my HR1's in a very small room and only 5 feet apart and slightly towed in toward the couch. The couch is 9 feet back. The imaging is incredible and the soundstage is extremely deep. I wish the room was twice as big.

Anyway, its a great looking room!

Ken

Mr. Widget
10-02-2004, 05:07 PM
Originally posted by ooppalla
...but they seem a little harsh in the upper mid ranges.

I have an opportunity to buy from the same seller a Hafler P-3000 (150 rms) or a QSC USA900 (225 or so rms)


Either of those amps should sound better than the Yamaha receiver. I own a P-3000 and think it is a decent amp. I don't know anything about that QSC amp, but other QSC amps I have heard sound pretty good too. Neither of these amps are top drawer, but they may be all you need. I agree with you about not needing additional power.

The harsh upper midrange you describe could be transistor hash. Many Japanese designed amps use great amounts of negative feedback to lower distortion. While it reduces Harmonic and IM distortion it tends to sound hard and unnatural. It could also be due to diaphragm fatigue. Alternatively it may be that you are sensitive in this region and have an issue with the sound of the the 2416H driver.

I would borrow a better amp and see if that solves the problem. I expect it will help but may not completely alleviate it.

Widget

ooppalla
10-03-2004, 12:34 PM
Originally posted by Zilch
Naw. 6230 or 6260. Both under $200 on eBay nowadays.... :-) Sorry for my ignorance. I looked at the CJ web site and these models were not listed... Do they have a frist or last name?

Zilch
10-03-2004, 01:25 PM
Well recommended in this forum. Here's the brochure (pdf) from JBL Pro. (http://www.jblpro.com/pub/obsolete/6200ser.pdf)

6230 will drive 4425's nicely. For subs, use 6260....

They're clean, quiet (no fans) workhorses, and plenty of them available at reasonable prices lately....

Jontherev just bought some. Watch for his review of their performance in a week or so....

Zilch
10-04-2004, 12:27 PM
e.g.:

ooppalla
10-04-2004, 07:56 PM
Thank you. Nice speaker stand... what can you tell us about it?

Zilch
10-05-2004, 02:12 PM
Originally posted by ooppalla
What can you tell us about it? This help? [Heh, heh....]

4343mod
10-10-2004, 12:24 PM
Originally posted by Zilch
This help? [Heh, heh....]

Wow, that is a thing of beauty. Do you have 2 of them? *drool*

Zilch
10-10-2004, 04:18 PM
Originally posted by 4343mod
Do you have 2 of them?Not that I'd part with, alas.... :p

You can trust my amp recommendation, tho....

4343mod
10-10-2004, 07:56 PM
Originally posted by Zilch
Not that I'd part with, alas.... :p

Oh, I didn't mean to suggest that, just was wondering if you are fortunate enough to enjoy stereo bass using 2 of those. What model sub is that anyway? Are they ultra rare?

Zilch
10-10-2004, 08:30 PM
B460 (http://www.lansingheritage.org/html/jbl/specs/home-speakers/1983-b380-b460.htm)

See also. (http://www.lansingheritage.org/html/jbl/specs/home-speakers/1982-l250-b460.htm)

Build yer own. (http://www.lansingheritage.org/html/jbl/reference/technical/1983-subs.htm)

Maybe 10 or so here in the forum. Bunch more built their own, seems like....

Subwoof output usually sums the L & R. I've seen some recent literature arguing there's value in keeping them separate, tho. Gotta build me another BX63A to find out....

These big subs need LOTSA power. If you hook two in parallel, a bridged amp delivers more and can handle it.

e.g., 6260 delivers 150 WPC stereo, 600 Watts mono bridged into 8 ohms. It's not spec'd for 4 ohms, alas.

Mackie 1400i is 300 WPC stereo into 8 ohms, 1400 Watts mono bridged into 4 ohms.

Running two subs in close proximity confers an additional 3 dB SPL through mutual coupling, as well.

A single 6260 in dual mono has been plenty enough for me.