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tjm001
02-02-2015, 01:22 PM
What are some good amp choices to power a JBL L300 or equivalent system without going off the deep end? Thanks.

hjames
02-02-2015, 01:39 PM
What are some good amp choices to power a JBL L300 or equivalent system without going off the deep end? Thanks.

Do you like the tubes, or silicon powered amps?
I have a home brew L300 type clone and have run it with a 60w/ch Jolida Tube amp, and in the past I ran them
with some transistor amps that were more overkill - JBL/UREI 6260, Adcom GFA555, and B&K ST202+
All 3 had more power than needed (est 200w/ch) but did allow for a tight bass response.

Doc Mark
02-02-2015, 01:52 PM
Hi, tjm001,

We usually use an Harman/Kardon HK870 amp with our L300's, and love the sound. The amp is just rated for 100 WPC, but being a "high current" capability amp, it can deliver more clean power, when needed. I've also tried our Crown DC300A amp with it, and the sound is most excellent, and in truth, a bit tighter, and with more snap. Last, I did hook up a huge brute of a Peavey amp the CS1200X, and also thought that amp sounded great with the L300's. Didn't like the fan noise of the Peavey, though. I hope that helps you. Take care, and God Bless!

Every Good Wish,
Doc

tjm001
02-02-2015, 01:56 PM
I don't have a bias either way. I know a lot of people are tube purists. I was trained in electronics way back in the 60's both ways. I guess my main consideration is not going over around $500 or so if that's possible.

BMWCCA
02-02-2015, 05:05 PM
I always take the opportunity to mention what has worked well for me for the past four decades.

My 4345s are bi-amped using Crown PS400 and PS200 amps. They're inexpensive, bullet-proof, and have a consistent resale value that makes them a no-brainer purchase, even if you somehow don't end up liking them. Alternately, I previously used the slightly older design (though their timeline actually started earlier but ended later) DC300A-II and D150A-II.

The L300A tech sheet shows a value for the maximum amplifier power of 300wpc for the L300 and 400wpc for the L300A. With a sensitivity spec of 93dB @ 1-watt, you won't need that much to make you happy. The PS400 is nearly 200wpc and the PS200 around 100wpc. Expect to pay around $300 for a nice PS400 and around $200 for a nice PS200. If you're looking for aesthetic and cosmetic perfection, add another hundred to those numbers. Those price haven't changed much in a decade, though the same can't be said for the L300!

I also have a Soundcraftsmen Pro-Power-Four that sounds great. I know Fred Sanford and HJames here have had great success with Adcom amps on their similar systems.

And $500 will buy a brand-new Emotiva XPA-200 rated at 150wpc at 8ohms.

ivica
02-03-2015, 04:57 AM
What are some good amp choices to power a JBL L300 or equivalent system without going off the deep end? Thanks.

Hi tjm001,

May be Rotel RA-980BX would be acceptable.

Regards
ivica

Dave_72
02-04-2015, 05:29 AM
A used Bryston 4B SST would be nice. Or an old (or older) Krell, McIntosh, or Threshold in good shape. None of those are bank breakers and they're top notch amps despite their vintage. I know many would disagree with me here, but I would stay away from pro stuff...well maybe just on the woofers if you were to bi-amp (providing those are bi-ampable to begin with!) I'm one of the few ocd audiophiles around here, you see. Now where did I put my room tuning magic pebbles. heh. :D

BMWCCA
02-04-2015, 05:56 PM
A used Bryston 4B SST would be nice. Or an old (or older) Krell, McIntosh, or Threshold in good shape. None of those are bank breakers and they're top notch amps despite their vintage. I know many would disagree with me here, but I would stay away from pro stuff...well maybe just on the woofers if you were to bi-amp (providing those are bi-ampable to begin with!) I'm one of the few ocd audiophiles around here, you see. Now where did I put my room tuning magic pebbles. heh. :D

Those are great amps, but likely will require 4-times the OP's stated budget.

I'm not really sure what gets everyone's panties in a wad about "pro" amps. The Crown D-series and P-series have been sold for home hi-fi system use for decades. They don't have fans, they sound very musical, they are very robust, and they fit the budget.

Can't tell you how many times I've mentioned my first Crown was purchased new from a dealer that also sold McIntosh. I bought the Crown on their recommendation to replace a Fisher SA1000 tube amp. I brought it in during one of their Mac Clinics with the C20 I had paired with it and the Crown guys could not have been more complimentary about its performance in their tests. It wasn't really a cheap amp back then, either. My original receipt from 1974 shows my D150 at $399 which subsequently went up to $499 on a price list for the D150A.

Mr. Widget
02-04-2015, 06:50 PM
Can't tell you how many times I've mentioned my first Crown was purchased new from a dealer that also sold McIntosh.Too many? Just kidding.

I remember in my home town there was an older stereo shop that sold the Crown D-Series amps and preamps... but they also sold Klipschorns. :D


Widget

Dave_72
02-04-2015, 08:00 PM
Those are great amps, but likely will require 4-times the OP's stated budget.

I'm not really sure what gets everyone's panties in a wad about "pro" amps. The Crown D-series and P-series have been sold for home hi-fi system use for decades. They don't have fans, they sound very musical, they are very robust, and they fit the budget.

Can't tell you how many times I've mentioned my first Crown was purchased new from a dealer that also sold McIntosh. I bought the Crown on their recommendation to replace a Fisher SA1000 tube amp. I brought it in during one of their Mac Clinics with the C20 I had paired with it and the Crown guys could not have been more complimentary about its performance in their tests. It wasn't really a cheap amp back then, either. My original receipt from 1974 shows my D150 at $399 which subsequently went up to $499 on a price list for the D150A.

Au contrare, the OP did not state his budget. Just stated "without going off the deep end."

Anyway, why do you say 4 times the price. I don't think that this is so.

As far as Crown is concerned, I heard the Macro Reference a long time ago. It was ok, but it had a "dark" almost shut-in sound. It wasn't lively or with enough clarity. Just my opinion here. But, there's a lot of other brands that share that characteristic. Of course I'm not questioning the Crown's ability to put out power. It does. Very much so. But is it very musical? Not in my opinion. And you can't listen to measurement graphs, you have to use your ears! :D

BMWCCA
02-04-2015, 08:15 PM
Au contrare, the OP did not state his budget. Just stated "without going off the deep end."

Anyway, why do you say 4 times the price. I don't think that this is so.

As far as Crown is concerned, I heard the Macro Reference a long time ago. It was ok, but it had a "dark" almost shut-in sound. It wasn't lively or with enough clarity. Just my opinion here. But, there's a lot of other brands that share that characteristic. Of course I'm not questioning the Crown's ability to put out power. It does. Very much so. But is it very musical? Not in my opinion. And you can't listen to measurement graphs, you have to use your ears! :D

Maybe not in the first post:

I guess my main consideration is not going over around $500 or so if that's possible.

I'm not talking mega-power amps, though I do own a Crown Studio Reference-II. I'm talking 90-to-200wpc. Can I assume you've never listened to a Crown D- or P-series amp?

Dave_72
02-05-2015, 12:42 PM
Maybe not in the first post:


I'm not talking mega-power amps, though I do own a Crown Studio Reference-II. I'm talking 90-to-200wpc. Can I assume you've never listened to a Crown D- or P-series amp?

Oh ok. I stand corrected! No, no I have heard a D- or P- series Crown amp. I did not intend to judge the whole make. Sorry if it came off that way. I was just merely relaying my experience with a Crown amp.

Anyway, if he can stretch his budget, here's a decent amp. Plus, he can send it to Bryston for a check up, and they probably won't charge him much...

http://app.audiogon.com/listings/solid-state-bryston-4b-power-amp-788-2015-01-21-amplifiers-10012-new-york-ny

speakerdave
02-09-2015, 11:53 AM
Most of us have been assuming you meant power amp. Do you have a preamp?

The problem I have with used pro amps is that my experience with buying them on eBay was not positive enough to recommend it.

With the budget you mentioned (and if you have a preamp) you might consider a Harman Citation series amp, the Twenty-Two being the preferred one, just for the power.

Understand--ANY used amp should be checked out before hooking it up to your valued speakers.

In my more trusting days I joyfully connected a Crown D300A to a pair of AR3's, but the joy turned to horror as I watched the smoke curl up from the center of the woofers.

BMWCCA
02-09-2015, 12:41 PM
The problem I have with used pro amps is that my experience with buying them on eBay was not positive enough to recommend it.

With the budget you mentioned (and if you have a preamp) you might consider a Harman Citation series amp, the Twenty-Two being the preferred one, just for power.

Understand--ANY used amp should be checked out before hooking it up to your valued speakers.

In my more trusting days I joyfully connected a Crown D300A to a pair of AR3's, but the joy turned to horror as I watched the smoke curl up from the center of the woofers.
Yeah and I'm sure we'll hear about some Phase Linear fire, too. Everyone has their sob story but it's never happened to me. Notice I did not recommend the D300A. Isn't that a DC300A anyway?

speakerdave
02-09-2015, 12:59 PM
Yeah and I'm sure we'll hear about some Phase Linear fire, too. Everyone has their sob story but it's never happened to me. Notice I did not recommend the D300A. Isn't that a DC300A anyway?

It's not about you, and it's not a general indictment of Crown. I have a PL 2 which I like, and I gave my son a 150A which has been very good. My story was told as a cautionary tale for the benefit of the OP and was not meant to put anybody's panties in a bunch. It just happened that it was that amp and, yes, I did mention the brand because being Direct Coupled there is that particular risk.

BMWCCA
02-09-2015, 08:12 PM
It's not about you, and it's not a general indictment of Crown.

But it is about the Original Poster who asked for an amp under $500 and hasn't gotten a lot of help. I have three PS400s and probably six PS200s, and none of them has blown up anything in several decades of use.

The poor OP just wanted some suggestions and he got two posts saying why he shouldn't choose "pro amps" and two posts specifying problems with two different specific Crown amp models, neither of which where in my original recommendation and only one of which even met the OP's price limits.

I'm just trying to help answer the guy's questions, but if y'all wanna use me as the straight man for your war stories, be my guest! :)

Not that any of this makes much difference since the OP is currently a one-post wonder and has yet to return.

And he's in Virginia, where (if we only knew where) he could probably get a lot of help—and maybe even the loan of an amp to try.

martin2395
02-10-2015, 12:23 AM
No one has mentioned yet that a separate power amp will probably need a preamp ;)

Old Bryston 4B could fit the bill but we are speaking about 30+ years old gear that could've been abused and even though it will most probably need some TLC.
The thing with those vinage JBL's is that the horn-lens combination is painfully revealing (way more than most of the modern gear) and requires careful matching. With a grainy, brutal sounding amp like the Phase Linear they will sound just nasty.

It's not the easiest task to find a suitable amp for them when you're on a budget. The big "15 loves powerful transistors but at the same time it must have enough finesse and smoothness for the mid and high region.

audiomagnate
02-10-2015, 10:51 AM
Mine sounded wonderful on my old Nak PA-7 (usually over $500) but also with a BGW 620B (same power but well under $500). No fans and plenty of current capability are what I look for in an amp.

Dave_72
02-10-2015, 01:44 PM
No one has mentioned yet that a separate power amp will probably need a preamp ;)

Old Bryston 4B could fit the bill but we are speaking about 30+ years old gear that could've been abused and even though it will most probably need some TLC.
The thing with those vinage JBL's is that the horn-lens combination is painfully revealing (way more than most of the modern gear) and requires careful matching. With a grainy, brutal sounding amp like the Phase Linear they will sound just nasty.

It's not the easiest task to find a suitable amp for them when you're on a budget. The big "15 loves powerful transistors but at the same time it must have enough finesse and smoothness for the mid and high region.

Yeah, true. So are you saying to get an integrated?

Well, the Bryston would be the smallest risk as you can send it to Bryston and have them check it out and/or fix/update it for a small fee. An old Aragon or B&K might work too.

I personally would stay away from Adcom, Rotel, and NAD just to name a few. They are cheap, but they really don't sound that great, imo. It's not the real stereo sound where you can't discern any sound coming from the speakers.

I see. Yeah, I guess bi-amping would be a good idea. That didn't dawn on me until now.

martin2395
02-10-2015, 02:26 PM
For $500 I would probably go for a integrated as finding a decent pre/power combination for $500 may be tricky but you can always go bargain hunting ;)

I think that Rotel is an 'OK' brand, NAD not really because even though they may sound decent (I liked the C372, lively sound and punchy bottom) they are full of very cheap parts and overall their build quality is low.

A Denon PMA-1560 could fit the bill if you can find one for sale. I delivers a healthy 150W @ channel at 8 ohms and has great control on the bass.

BMWCCA
02-10-2015, 06:16 PM
No one has mentioned yet that a separate power amp will probably need a preamp ;)
If someone says "amp", I assume they mean amplifier. If they're asking for an amp, I assume they already have a pre-amp. If they have a pair of L300s I assume they know enough about hi-fi to know the difference between an amplifier and an integrated amplifier. But then I almost went out of business once underestimating the stupidity of the general public.

And still the OP has yet to return. :dont-know:

Maybe you're right, and my assumptions were all about me. I guess I have about nine pre-amps around, if you count the Emotiva XDA-2, the Soundcraftsmen Pre-Tuners, and several Soundcraftsmen Pre-EQ combinations. I haven't owned an integrated or a receiver since I dumped my Kenwood back around 1968 and replaced it with a Mac C20 and a Fisher SA1000.

tjm001
02-11-2015, 02:10 PM
If someone says "amp", I assume they mean amplifier. If they're asking for an amp, I assume they already have a pre-amp. If they have a pair of L300s I assume they know enough about hi-fi to know the difference between an amplifier and an integrated amplifier. But then I almost went out of business once underestimating the stupidity of the general public.

And still the OP has yet to return. :dont-know:

Maybe you're right, and my assumptions were all about me. I guess I have about nine pre-amps around, if you count the Emotiva XDA-2, the Soundcraftsmen Pre-Tuners, and several Soundcraftsmen Pre-EQ combinations. I haven't owned an integrated or a receiver since I dumped my Kenwood back around 1968 and replaced it with a Mac C20 and a Fisher SA1000.

Thanks all. I was out of town and traveling the the last 10 days or so. I appreciate all the info. Yes, I am aware of the need for a preamp. Believe it or not I've been using an ancient Dynakit preamp that I built back in the 1960s. That was going to be my next post. Thanks again.
Tom

Dave_72
02-12-2015, 02:27 PM
For $500 I would probably go for a integrated as finding a decent pre/power combination for $500 may be tricky but you can always go bargain hunting ;)

I think that Rotel is an 'OK' brand, NAD not really because even though they may sound decent (I liked the C372, lively sound and punchy bottom) they are full of very cheap parts and overall their build quality is low.

A Denon PMA-1560 could fit the bill if you can find one for sale. I delivers a healthy 150W @ channel at 8 ohms and has great control on the bass.


Yeah, probably. I agree with you on Rotel and NAD. I'm not familiar with that Denon unit. But, I know, like Yamaha, Onkyo, Pioneer, etc. are capable of making great stuff.

martin2395
02-12-2015, 03:18 PM
Rotel is a strange bird because the older ones were built in Taiwan and somewhere in the mid 90's their moved the production to China and their quality dropped.

I had a Taiwan Made RA-980BX myself and it had amazing build quality, that thing was literally FULL of Rubycon Black Gate F caps and even the 4x 10.000uF PSU caps were sourced from BHC/Aerovox, custom made for Rotel.
Rotel specs it as 2x100W / 8 ohms and 2x 190W / 4 ohms (DIN) with peak current delivery of 80A.

The Denon I mentioned in my previous message was TOTL integrated at the time, I owned various models from the x60 range and they all sounded at least good.
I also like the older Sony ES amps a lot but they all suffer from cold solder joints, literally everywhere. The whole board has to be redone.

Dave_72
02-13-2015, 03:40 PM
Rotel is a strange bird because the older ones were built in Taiwan and somewhere in the mid 90's their moved the production to China and their quality dropped.

I had a Taiwan Made RA-980BX myself and it had amazing build quality, that thing was literally FULL of Rubycon Black Gate F caps and even the 4x 10.000uF PSU caps were sourced from BHC/Aerovox, custom made for Rotel.
Rotel specs it as 2x100W / 8 ohms and 2x 190W / 4 ohms (DIN) with peak current delivery of 80A.

The Denon I mentioned in my previous message was TOTL integrated at the time, I owned various models from the x60 range and they all sounded at least good.
I also like the older Sony ES amps a lot but they all suffer from cold solder joints, literally everywhere. The whole board has to be redone.

I see, very well then. Well, I guess it's not all Rotel, just most of it. I take it that amp was an exception to the rule so to speak.

That's cool about the Denon. I'm a big fan of Japanese high end like Accuphase and Luxman. But, most recently, Pioneer (mainly TAD) and Yamaha have shown what they can do as far as high end is concerned.

Audiobeer
03-04-2015, 12:00 PM
Yeah, true. So are you saying to get an integrated?

Well, the Bryston would be the smallest risk as you can send it to Bryston and have them check it out and/or fix/update it for a small fee. An old Aragon or B&K might work too.

I personally would stay away from Adcom, Rotel, and NAD just to name a few. They are cheap, but they really don't sound that great, imo. It's not the real stereo sound where you can't discern any sound coming from the speakers.

I see. Yeah, I guess bi-amping would be a good idea. That didn't dawn on me until now.


Don't sweat it. I could bi-amp my pro version, the 4333's but not my L300s.

Dave_72
03-05-2015, 11:03 AM
Don't sweat it. I could bi-amp my pro version, the 4333's but not my L300s.

Ok, no problem. Thanks.

antoninus9
03-22-2015, 10:21 AM
What are some good amp choices to power a JBL L300 or equivalent system without going off the deep end? Thanks.

I would refer you to JBL's power requirements doc first: http://www.jblpro.com/ProductAttachments/spkpwfaq.pdf. The speakers will work with many amplifiers, but if accuracy is the goal, then the choices become easier. The L300 has very large woofers that perform more accurately when the dampening factor of the amplifier is high (500-1000). (See Bryston's FAQ on Dampening Factor http://www.bryston.com/pages/faq.html.)

You'll probably want to use 10 AWG wire (Belden is a good choice).

In this case the question becomes "which amplifiers meet this criteria?"

Please know that I am not recommending Bryston by referring to their FAQ. There are many amplifiers that will work well.

BMWCCA
03-22-2015, 04:28 PM
The speakers will work with many amplifiers, but if accuracy is the goal, then the choices become easier. The L300 has very large woofers that perform more accurately when the dampening factor of the amplifier is high (500-1000). (See Bryston's FAQ on Dampening Factor http://www.bryston.com/pages/faq.html.)

BTW, it's Damping Factor, not "dampening". Many would say it's an over-rated spec and that anything over 200 is enough. I have Crown amps where the Damping Factor is shown as >20,000. Does that make them 40-times more capable than the Brystons? :dont-know:

antoninus9
03-22-2015, 07:19 PM
Auto-correction doesn't always auto-correct correctly. :)

In the best case scenario about 100 damping factor is all you can expect, regardless of amplifier. It's true that the impact of damping can be overstated, especially with smaller drivers. My experience has been that higher damping amps have much better control over larger woofers. Many people claim it causes the system to sound "brighter," but I believe this perception is primarily related to woofer control. I agree with the engineers at JBL that high power amplifiers work better with these speakers, allowing them to reveal subtle details that are less apparent with less power. I've also noticed that the engineers at Harman International almost always build spec their best amps for high current, wide bandwidth, and high damping factor. This falls right in line with the white papers from JBL, and my experience using their products over the past 35 years.

This is why I provided the two links, instead of recommending any specific amplifier. In my opinion, the brand and model are irrelevant. To me, the most important factors are how the amplifier operates under real world conditions, and how that impacts the sound of my system.

If it makes you happy to believe that Crown are 40 times more capable than Bryston, or any other amplifier, then I'm happy to agree. I'm pulling my old Macro Reference out of the closet tonight! (Wow! I forgot how much it weighs. Better get the wife to help me.) :D

BMWCCA
03-22-2015, 10:17 PM
If it makes you happy to believe that Crown are 40 times more capable than Bryston, or any other amplifier, then I'm happy to agree. I'm pulling my old Macro Reference out of the closet tonight! (Wow! I forgot how much it weighs. Better get the wife to help me.) :D

Again, you seem to have missed the humor. I blame myself . . . and the medium.

We all know damping factor is important. We also have learned that the way the factor is stated varies widely by manufacturer. I could pull out my Studio Reference-II rated at >20,000 but the wimpy PS400 with its meager >400 damping factor sounds just fine to me on the 4345s. It seems to be quite capable of keeping the 18-inch woofer from sounding flabby.

Best wishes. :cheers:

ivica
03-23-2015, 04:06 AM
Again, you seem to have missed the humor. I blame myself . . . and the medium. We all know damping factor is important. We also have learned that the way the factor is stated varies widely by manufacturer. I could pull out my Studio Reference-II rated at >20,000 but the wimpy PS400 with its meager >400 damping factor sounds just fine to me on the 4345s. It seems to be quite capable of keeping the 18-inch woofer from sounding flabby. Best wishes. :cheers:

Hi,
If talking about the amp output impedance, not to be forgotten the internal (DC) driver's impedance ( Re) is "the player in the game" ,
as it has to be added to the amp output impedance (Rg).

regards
ivica