xavionics

Hey Kurt, Greg is exactly right. We get no free ride in this world. High efficiency High power handling High accuracy Pick any two... There's a phenomena in electric motors (and a dynamic driver is a motor) where the more physical resistance you apply to its motion, the more current (and less impedance) it will require to keep driving. OTOH, if you spin a motor externally (say, via a drill), the electrical power applied to the motor will require minimal current. As Greg stated, at around 50 Hz it seems common for a woofer to peak in resistance. If I have this correct, the reason for this is at this frequency, the mechanical desire for the driver to return to its neutral position is around 180 degrees out of phase with the electrical motors desire to move the voice coil. Think of it this way - a pulse pushes the cone outward. As the cone returns to rest, another pulse tries to push the cone outward at the same time. This second pulse needs more power - not only to produce the movement intended, but to counteract the opposing momentum the cone's mass has stored. OTOH, when the pulses are at such a frequency that they get the cone to 'bounce' - less power is required to create the cone's movement because the cone is already moving ahead of the pulse. So, very little effort is required and the impedance (resistance to the pulse) becomes less. This is the frequency where the driver's impedance dips to minimum. Unfortunately, you cannot engineer the driver/cone/motor/suspension/etc. to manage all parameters optimally. Gain, Like Greg stated, you gotta work with what ya got. There are other things going on as well. I think this would be a fun conversation over some adult libations. To illustrate all this: I bought a stereo 8-track player when I was in the 6th grade. It didn't take me long to build some external speakers with parts bought at Radio Shack. I know nothing of series or parallel connections. Two 7" full range drivers per enclosure were likely wired in parallel and connected to the internal amp outputs. There were certain musical passages that would put the speakers into resonance. It drew so much current that the power supply couldn't keep up and the tape drive would sag and slow down. I listened to one of these albums yesterday while working in the shop. I kinda chuckled to myself, remembering those days so long ago.

Time to clear some cobwebs out of that old part of my brain and see if I can put together an explanation…🥱 In an AC circuit, impedance is the total of resistance, capacitive reactance and inductive reactance. Resistance is just that - straight up, one value, resistance to the flow of current. Capacitive reactance and inductive reactance can be thought of as resistance that varies with frequency. Capacitive reactance varies inversely to frequency. Inductive reactance varies directly to frequency. There’s a nice little read here on this: https://byjus.com/physics/reactance-and-impedance/ Add to this, in the case of a dynamic loudspeaker: The woofer voice coil is an inductor. It’s “impedance” (inductive reactance) varies with frequency. Add to this mix, though, are other properties of physics introduced by the movement of this inductor within the magnetic field, the mechanical resistance to movement of the whole piston (VC, its former and the cone), resonances, etc., and the impedance becomes a curve rather than a simple value. Throw a passive crossover with capacitors and inductors into the mix, and, well, you have a system impedance with a “nominal” impedance rating that varies with frequency. That’s my simplistic view anyway. Hope it helps. Feel free to add and/or correct if needed.

Good morning Ron and welcome aboard! All manuals we have available can be found under the “Manuals and Specsheets” tab above. At the bottom of the window that opens, you will find tabs linking the brands available. Click on the Sunfire tab and look for what you need.

Welcome to The Carver Site Don! Looks like you had a bug of OCCD (Obsessive Carver Collecting Disorder) back in '87. It appears it's been dormant for entirely too long. We'll fix that! Pull up a chair and sit a spell. You'll fit in here just fine...

Cool story! My first real system was pretty good. Or at least I thought so, until I happened to enter a high-end shop in Hong Kong many years ago. The notion that you can actually hear a difference between different amplifiers was eye opening! Been chasing more accurate sound ever since. Nice system! 👍👍

Kinda like an audio equivalent to a Picasso. Thanks for the introduction! I've heard of this album but have never listened to it. Maybe one day when I have the house alone... My only previous exposure to Beefheart is on the Zappa Live album Bongo Fury I received as a Christmas gift from my older brother. I just read the lyrics to all the songs on Bongo Fury, to refresh my memory. 1975 was one helluva year...

Welcome to the site @alf57! That’s a great way to jump back in to the hobby - buying two amp that need repair. Very well done, sir! And congratulations on both repairs. Pull up a chair and get comfortable - you’ll fit right in here. 😎

The sound of speakers, more than any other piece in the audio chain, is very subjective. As you just read two, differing opinions here. What I like may be different from what you like. And that’s a good thing! Google “stereo stores in my area” within whatever distance you’re willing to drive. Go listen to as many different brands as you can. Bring some music you know well. I was laid up after having knee surgery some years ago. I was bored, and drove an hour to visit a store I hadn’t heard of before. I came in on crutches. I spent about two hours there. Guys who work in these places love listening to music and discussing all things audio. Within a year, I bought a DAC from them. If you are looking to buy new, and find something you like within your budget, be sure to patronize the brick and mortar places who graciously allowed you to audition their wares. Above all, have fun!

I've been a fan of the Klipsch Heritage line for decades. Seems every time I hear them I like what I'm hearing. KG-4's have been part of my main rig since around '89. A single pair driven by a c-1 and m1.0t was a favorite, especially while I was still in an apartment. If buying used, it seems you can't go wrong in that if you don't care for them you can resell them.

Welcome aboard @Carverrocks! I don’t know what amp might be preferred, but I have a pair of ALSIII’s I have run with a stock m1.0t, TFM-25, Pioneer Spec 2 and Spec 4, and my Bob Carver RAM 285. Currently, they are in my basement system being driven by a PT-2400. Each of these amps have driven them well. But the PT-2400 has SO MUCH power that it really makes them sing! Enjoy those speakers, they really are something special.

Welcome aboard @Lovage, glad to have you! Mr @AndrewJohn will get you set up with some Carver gear - he is an enabler extraordinaire with a long, distinguished resume! 😁

Thats a good enough reason to me! I'm glad you got it sorted out and working. Thanks for sharing your journey.

It seems to me, the m1.0t (both) should be non-inverting (has the stereo/mono switch). In the non inverting model, the two negative (-) speaker leads are electrically tied together. The reason for this, in my mind, is that the negative (-) posts on the speakers are likely tied together. Personally, I see little advantage in doing it this way. Again, in my opinion, if you are going to use multiple amps, go with an active crossover and bypass the internal passive crossover completely. ***This, of course, creates a whole new world of trying different active crossovers…*** Ask me how I know. 🤔 P.S. All of my experience in this has been with two way speakers.

Welcome to the site @wicked1340! Damn, laundry AND grocery lists - nothing like a good hearty intro! 👍👍 Nice to have another car stereo aficionado on board. I have a pretty fair collection of a/d/s stuff, currently packed away for an upcoming move. My first Carver car amp awaits repair.

Good morning Roland, and welcome to the Carver site! I'm sorry to read about your circumstance. Odd that someone would take the transformer and not the whole amp! Anyways, I searched our database and a few online resources and could only come up with an Owners manual for your amp. This amp was made while Phoenix Gold owned the company. According to the back page of the owners manual, they refer to a phone number and a website - carver pro.com - which appears to be a dead site. Phoenix Gold appears to be in business. It looks like they are only into car audio but it may be worth reaching out to them. Maybe they still have literature on the Carver Pro stuff: https://archive.phoenixgold.com/pages/contact-us Good luck with your endeavor!

Listening to the AXPONA 24 playlist at my buddy’s place in Green Bay…

Good morning bigeyesteve and welcome aboard! There is a place where reputable PL service parts are available: https://www.whiteoakaudio.com And there is another site where PL fans share info: https://forums.phxaudiotape.com Enjoy your newly acquired gear!

Welcome aboard Dan! I love Hilton Head. Are you a year-long resident or do you “summer” there?

Yes, show us your gear! Don't make us throw beads... Oh, and welcome aboard!

Maggie MGIIa's in series for center channel - Holy crap, that's brilliant! Welcome! You'll fit in very well here...👍

Seems to be the case with the pro amps. Poor things take a beating!

Currently, my 'go to' track is Stalin Malone off the Elvis Costello Album Spike. From the snap of the snare to the textures of the brass to the pprrraatt of the tuba.... After the performance, they may remain (or may no longer be) my dream speakers.

Welcome aboard tankdcrank! This site is about Carver stuff, but all gear is appreciated. Pull up a chair, pour a cold beverage of your choice, and consider what your goals might be in a Carver system. You’ve found the mother-load of info here, glad you found us! You’ll be able to post pics after a small bit of activity. Please feel free to describe what you have and/or what you seek.

Patience and scouring eBay will eventually yield the Carver Autosound system dreams are made of. It took over two years to create the a/d/s system I used to have in my Odyssey…

I placed an order yesterday for new electrolytic caps for my ALS III’s. I went cheap on this event, not opting for higher-end caps. One of these crossovers has taken out a channel on two different amps…🤨