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JBLAddict
11-15-2008, 08:36 AM
silly question, but have only owned integrated, looking to buy more power for my "new" L5s

if I pickup a used crown/soundcraftsman so regarded here, can the CD signal be connected directly and amplfied or is a pre-amp required for signal processing prior??

thanks

johnaec
11-15-2008, 09:12 AM
Without a preamp all you'll have control over is the volume, assuming either the CD player or the amp has a volume control. It can be done if that's all you want, (like for testing, etc.), but you'll have far from optimum capabilities, and that's assuming the levels are somewhat compatible. You'll have no tone adjustment, etc., but it should at least function.

John

Mr. Widget
11-15-2008, 09:36 AM
You'll have no tone adjustment, etc., but it should at least function.None of the better preamps I've owned have had tone adjustment either.:D



...if I pickup a used crown/soundcraftsman so regarded here, can the CD signal be connected directly and amplfied or is a pre-amp required for signal processing prior??In the old days you needed a preamp as you could not run a power amp directly from a turntable or even a tape deck if you travel back in time far enough. :) These days most amps can be driven directly from a CD player. However depending on the input requirements of the amp, you may not have enough voltage to drive the amp to full power. You also need a CD player with a variable output... or an amp with pots on the input. Most amps do not have these controls (many do though) and most CD players do not have variable outputs.


Widget

porschedpm
11-15-2008, 11:01 AM
silly question, but have only owned integrated....

Many integrateds have the capability to split their pre-amp and amp sections. look for 'Pre-Out' jacks on the back of your integrated and if you have them you can use your integrated as a pre-amp.

spkrman57
11-15-2008, 11:19 AM
But I found using passive preamp (Potentiometer) to vary the level to the amp would sound very bright and thin.

I find using a preamp adds body to the sound.

This is especially noteworthy using tube amps.

To each his/her own though, YMMV!

Regards, Ron

BMWCCA
11-15-2008, 11:36 AM
Or you could over-complicate the issue: I'm currently listening to L7s through a CD player to a Soundcraftsmen Pro-Control Four pre-amp, looped through "loop 1" to a Soundcraftsmen Pro EQ 44 third-octave equalizer, then to a Soundcraftsmen Pro Power Four (probably around 300 wpc at the L7's 6-ohms). Whew! I think the cables cost more than the electronics. Sounds great though. Between tracks I'm a bit sensitive to the Soundcraftsmen's constant low-speed fan which the D-series and PS-series Crowns don't have and don't need. Sound-wise they're both excellent though you probably have a better chance finding a serviceable old Crown than a Soundcraftsmen. And Crown still supports them; Soundcraftsmen products are very much orphans these days.

I believe some here who've hooked a Crown power amp to the pre-out from some consumer integrated amps have complained about the low output, mostly because of a mismatch in the consumer pre-out level versus what the Crown really wants. Works fine, just most then think they're getting less power than what they had before. They're confusing power with volume though. Adjusting the Crown input attenuators to where your integrated amp's volume control is near 12-o'clock at normal listening level is all you should need to do. My L5s love the Crown PS-400, though with two pairs of L7s, I hardly even listen to the L5s anymore. ;) The Soundcraftsmen amp's whacked! The Pro Control Four volume control starts about 7-o'clock and by 8:30 or so it's too loud for my wife and the amp's LEDs are telling me I'm not even using the whole first watt yet.

Still I think you'd want a bit more control over the inputs and maybe some EQ that a good pre-amp will allow you. The wonderful thing about many Soundcraftsmen pre-amps is they were built for the consumer market and combined an octave EQ with normal pre-amp controls. A good late-model DX4200 is not very expensive. Even a DX4000 is a fine unit usually available for around $100. I only mention such brands because that's what I grew up using. I have very limited experience to guide me otherwise—and even less reason to change! Unlike my car choices where I sold Audi and Porsche for twenty years and wouldn't own either of them, certainly not over a good BMW. ;)

JBLAddict
11-15-2008, 11:41 AM
thanks for the answers, my situation is I have a 100WPC integrated Kenwood AVR, and I'm marveling at the L5 balance compared to my L100A, but keep hearing here that "a >200WPC amp of brand name X will make big difference", and I want to experience those heights

However, I don't want to redo my entire system having to buy/pair a preamp+amp, and wanted to see if by investing a few hundred in just an old amp, I could use this for optimal music, and go back to the integrated for HT.

the other thing that has me thoroughly confused is a brand new "reference line" amp from eg Marantz is over $5K but the RMS are still in the 110WPC range, about what I have now? So, assuming the signal cleanliness is orders of magnitude better than my current system, what happens to the wattage level being ultra critical as is stated on these boards ad nauseum? :blink:

BMWCCA
11-15-2008, 12:05 PM
thanks for the answers, my situation is I have a 100WPC integrated Kenwood AVR, and I'm marveling at the L5 balance compared to my L100A, but keep hearing here that "a >200WPC amp of brand name X will make big difference", and I want to experience those heights

However, I don't want to redo my entire system having to buy/pair a preamp+amp, and wanted to see if by investing a few hundred in just an old amp, I could use this for optimal music, and go back to the integrated for HT.That should work fine. Half the Crowns I'm talking about aren't rated any more powerful than your Kenwood but if you spend a hundred or two on a Crown PS-200, PS-400, D150A-II, or DC300A-II and don't like what you're hearing, you can always find someone who will pay you what you have in it. Your Kenwood's power rating may well be like comparing apples and oranges with even a Crown PS-200 which is also rated 100wpc at 8 ohms. I have several PS-200s and Crown D150A-IIs loaned out and no one's complaining, or even in a hurry to repair their broken amps. I'm just happy to have them getting some exercise!


the other thing that has me thoroughly confused is a brand new "reference line" amp from eg Marantz is over $5K but the RMS are still in the 110WPC range, about what I have now? So, assuming the signal cleanliness is orders of magnitude better than my current system, what happens to the wattage level being ultra critical as is stated on these boards ad nauseum? :blink:No comment. I've seen $10,000 18-watt amps though. My 34-year-old Crown still works great! ;)

Hoerninger
11-15-2008, 12:16 PM
But I found using ... (Potentiometer) to ... the amp would sound very bright and thin.

This indicates that the value (in Ohms) for the potentiometer was too low. The output impedance of source and the input impedance of the amp often perform a highpass. When dimensioned right the potentiometer is closest to a piece of wire :thmbsup: .
____________
Peter

JBLAddict
11-15-2008, 12:55 PM
Your Kenwood's power rating may well be like comparing apples

No comment. I've seen $10,000 18-watt amps though. My 34-year-old Crown still works great! ;)

point taken, thanks.....

Mr. Widget
11-15-2008, 06:11 PM
thanks for the answers, my situation is I have a 100WPC integrated Kenwood AVR, and I'm marveling at the L5 balance compared to my L100A, but keep hearing here that "a >200WPC amp of brand name X will make big difference"Every AVR I have heard has disappointed me. Also realize that if your Kenwood actually produces 100 watts, a 200 watt anything will only be 3dB more powerful... not really all that much of an improvement in headroom. This is not to say that a really good amp won't improve your system, but finding one that is really good for ~$200 is unlikely in my opinion.

There are those who like old Crowns or the old JBL /Ureis etc... you might find them better than your Kenwood, but then again maybe not.


...but if you spend a hundred or two on a Crown PS-200, PS-400, D150A-II, or DC300A-II and don't like what you're hearing, you can always find someone who will pay you what you have in it.True enough.


Widget

JBLRaiser
11-17-2008, 06:13 AM
silly question, but have only owned integrated, looking to buy more power for my "new" L5s

if I pickup a used crown/soundcraftsman so regarded here, can the CD signal be connected directly and amplfied or is a pre-amp required for signal processing prior??

thanks

Here are some completed listings;

http://completed.shop.ebay.com/items/Electronics__DYNACO-400_W0QQLHQ5fCompleteZ1QQ_dmptZVintageQ5fElectroni csQ5fR2QQ_flnZ1QQ_npmvZ3QQ_sacatZ293QQ_trksidZp328 6Q2ec0Q2em283

And if you want an excellent tube preamp, Dynaco made a good one.

http://completed.shop.ebay.com/items/Vintage-Electronics__PAS_W0QQLHQ5fCompleteZ1QQ_dmptZVintag eQ5fElectronicsQ5fR2QQ_flnZ1QQ_fromfsbZQQ_sacatZ14 998QQ_trksidZp3286Q2ec0Q2em283

Here are the specs:
http://home.indy.net/~gregdunn/dynaco/components/ST400/index.html

http://home.indy.net/~gregdunn/dynaco/components/PAS3X/index.html

These are extremely well designed units that have a huge following. Simple, reasonably priced and sound fantastic. These came as kits and factory wired. If possible, get a factory wired as they had the quality control in assembly. I have the ST-400 SS and a SCA-35 tube amp as well as a couple of PAS models and have enjoyed them very much.

boputnam
11-17-2008, 12:53 PM
(OT - apologies. But...)


... looped through "loop 1" ...I got confused.

Why use the "loop"...? It sounds like you've got the EQ in the signal path right where it should be - between the pre-amp and the amp.

BMWCCA
11-17-2008, 01:02 PM
Why use the "loop"...? It sounds like you've got the EQ in the signal path right where it should be - between the pre-amp and the amp.A good question, normally. The Soundcraftsmen Pro-Control-Four also has a "direct" button that cuts out everything except the volume control. In effect a "straight-wire" connection. If I just stuck the EQ in between the pre-amp and amp even with the EQ defeated the signal path would still run through the EQ and two more patch cords. Also the Pro-EQ-44 apparently won't pass a signal unless it has power to it and is turned on, even if the EQ is defeated. That seems a bit odd. Regardless, the pre-amp has two loop circuits using C-Mos switching so it's a real easy way to hook up the EQ, and easy to bypass it cleanly when I feel like it. Does that make sense? I trust your opinion on this more than mine! :thmbsup:

The documentation is a bit light on substance even though I have the owner's manuals for everything.

boputnam
11-17-2008, 01:16 PM
Yeah, that does make sense. (although I must think that if you're seeking that pure of a signal path there will be higher level gear in your future... :)).


The documentation is a bit light on substance even though I have the owner's manuals for everything.I see the schematics are available for purchase. It'd be interesting to see that, if you don't already have them.

FWIW, when I'm scoping out a console for an upcoming gig - which I do regularly, as we play in all varieties of festivals, venues, and clubs with gear I may not have many hours on - I invariably go straight to the EOM's website and get to the Block Diagrams. Answers every question I have and solves all sorts of confusion over syntax... :p

Anyway, thanks for the answer.

BMWCCA
11-17-2008, 01:43 PM
Yeah, that does make sense. (although I must think that if you're seeking that pure of a signal path there will be higher level gear in your future... :)).

Don't forget: Three college tuitions to pay! Maybe I've been deluding myself, but I've been pretty impressed with the Soundcraftsmen stuff as pre-amp-EQs for now over 25 years. Over the past year I've been enjoying using the Pro-Control-Four in my daughter's room system (L20t, Crown PS-200). Then I replaced it with a Pre-Receiver PT3 or something like that. Now that I've been trying out my new Pro-Power-Four I've been impressed with the Control-Four in a more critical listening environment using the L7s so much that I bought another one. But remember, I grew up with an 030 so what do I know? :)


I see the schematics are available for purchase. It'd be interesting to see that, if you don't already have them. I've been spoiled by Crown's support of their legacy stuff. Before Ebay profiteers upset the enthusiast market, Crown would give you free documentation in hard-copy form and pay the postage. Now at least they still offer most of it as a pdf archive. I even have the original info for my Mac C-20, so I appreciate what you're saying. I've not looked for the Soundcraftsmen equivalent, but I will. Thanks.

boputnam
11-17-2008, 02:23 PM
Don't forget: Three college tuitions to pay! Maybe I've been deluding myself, but I've been pretty impressed with the Soundcraftsmen stuff as pre-amp-EQs for now over 25 years. Ha! and yessir to all the above!

But Widget reminds:

None of the better preamps I've owned have had tone adjustment either.:D


I've been spoiled by Crown's support of their legacy stuff. Before Ebay profiteers upset the enthusiast market, Crown would give you free documentation in hard-copy form and pay the postage. Now at least they still offer most of it as a pdf archive. Yeah, I've found very few of those currently in business that do not offer / maintain an archive of manuals, and schematics, free. I thrive on that stuff. Certainly builds brand loyalty!

eBayer's thrive off copies of OOP stuff... :baby:

BMWCCA
11-17-2008, 03:22 PM
eBayer's thrive off copies of OOP stuff... :baby:Years ago I bought a DC300A-II from a group liquidating the detritus from the remodeling of some Lowes theaters. They had tons of Crowns so I bought one. Being the early days of Ebay I was surprised that despite their throwing it in a bag inside a box full of "peanuts" it actually arrived in working order. When I went on-line to buy a manual for it (didn't need one, just wanted one) I found myself in a bidding war for it on Ebay. I got so pissed when someone outbid me and the price escalated to beyond reason that I called Crown. They told me they still had DC300A manuals but only for the Series-II (:)), and would I like them to send me one free of charge? I even told them what they were bringing on Ebay and suggested to them that they might want to ask for a serial number for the product when someone requested a manual. I doubt they cared but they sure made me happy that day.

In their praise also, I bought an early D150 brand new back in '74 and sometime around 1981 it developed a slight hum in one channel. So I sent it back to them fully expecting them to charge me for a quality repair at four-years out of its original three-year warranty. They returned it promptly with a list of what they did, who did it, a full test sheet signed by another tech, and a bill for "no charge". Gotta love that customer service.

More to the point of this thread, back in the late Eighties or early Nineties I wanted another Soundcraftsmen pre-amp-EQ but there were no longer any dealers nearby. I called Soundcraftsmen and they sent me a nice reply in the mail with a list of dealers but said that since I was so far from any of their dealers they'd simple sell to me direct at 25% off list price, and included a price list and catalog of their entire line. If JBL can't place their products in a retail environment, maybe they should try a similar marketing plan with their former customers who have previously purchased their L-series speakers brand new! :D