KG-2.5.... which amp?

[tpg]

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[Deang]

Ya know, I really hate reading your posts with all those floppydoodle guys jumping around. It's annoying as hell, and I can't think straight.f>s>

I have the ProMedia 5.1's, and was hoping to be able to hook the KG-2.5's to the outs on my PM5.1 amp and use it with the sub and my computer. Well, the amp is 4 ohm per channel, and the speakers are 8 ohms.f>s>

Let me get this straight. You are going to hook up 4 KG 2.5's to an amp designed to push itty bitty little computer speakers? It should actually work. Your impedence issue is a non-issue. The PM5.1 amp is rated at 4 ohms because it is designed to drive multiple sets of speakers -- which is exactly what you are doing anyways. Hooking two sets of 8 ohm speakers gives you 4 ohms -- which is what the amp is rated at.f>s>

Also, the PM5.1 amp only puts out 60 watts per channel, and the KG-2.5's need 75-375. If I was to bi-amp them using two channels for each speaker, tis would correct the impedence issue and help with power... right?f>s>

The power handling specification for the KG2.5 is 75 watts (maximum) and 375 watts PEAK. They don't NEED 75 watts. 75 watts is the most they can take. You have 60. We already dealt with impedence. You have 4 channels at 60 watts each. Also, I don't really understand your concept of biamping. Best not to try any bizarre wiring schemes with an amp already designed to run 4 speakers.f>s>

Also, when the time comes for me to get a reciever, which one would suit these best? I guess it would have to be a 5.1 reciever, since I do have 2 pairs. How many watts per channel should I look for? What are some good ones that are fairly cheap... <$150f>s>

Sorry, but this Sony is the best I can do for you.

Good luck!

f>s>

------------------

Deanf>s>

AE-25 Super Amp DJH * S F Line 1 * S9000ES * HSU x-over * SVS CS+ * Klipsch RF7s f>s>

Psalm 122:6f>c>s>

This message has been edited by deang on 06-23-2002 at 11:58 AM

[tpg]

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[Deang]

The KG series are NOT shielded.

There are several ways to biamp - your way is not one of them.

Horizontal Biamping: You have a set of speakers with birwiring capability. That is, each speaker has four 5-way binding posts on the back -- 2 for the high frequency driver (1 positive and 1 negative), and 2 for the low frequency driver (1 positive and 1 negative). You then use two amplifiers, and use one for the highs, and the other for the lows.

Vertical Biamping: Same as above except you use one amp for the left channel, and the second amp for the right channel. You use two separate sets of speaker cables for each speaker, and then join the inputs of the amps together using "Y" connectors.

Pro-Biamping This is where the frequencies going to the drivers are "split" in front of the amps. That is -- electronic crossovers are used in front of the amps and then the amps feed the drivers directly.

HT-Biamping Simply adding a sub does this. The low frequencies are sent to the sub and the crossover sends everything else to the mains.

Your Promedia system is a form of biamping, simply because it uses a sub and splits the signals. All biamping involves the idea of splitting the signals and moving them to the appropiate drivers.

What you are describing is not "biamping". Whatever one chooses to call it -- I don't think it sounds like a good idea.

Your Promedia system's amp resides inside the sub right? It is a 500 watt digital switching amp. There is ONE amp with dual power supplies. One feeds the sub and the other feeds the remaining 5 channels (you actually have 50 wpc). The nominal impedance of the SYSTEM is 4 ohms.

What I believe is happening here is that the Promedia satellites are probably 8 ohms speakers, and when they are all hooked up to the amp -- the impedance drops to 4 ohms. It's what happens whenever you hook up multiple sets to an amp -- the impedance is halved.

Now, if you hook up all 4 KG's -- you will still be at 4 ohms as far as that 2nd power supply in your sub is concerned.

If you hook up just 2 KG's, your impedance will be 8 ohms, but your usable POWER will drop to around 34 wpc.

So, if you hook 8 ohm speakers to an amp rated at 4 ohms, your power rating drops by about 1/3 -- and if you hook 4 ohm speakers to an 8 ohm rated amp, your power goes up about 1/3 of the rated power.

If you use all 4 KG's in your situation, the danger is playing the system too loud and going into clipping and frying a tweeter. If you use 2 KG's and you drive it too hard, you risk melting down the amp in the sub.

Either way, be cool and don't crank it too loud -- and scrape that money together for the receiver!!

f>s>

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Deanf>s>

AE-25 Super Amp DJH * S F Line 1 * S9000ES * HSU x-over * SVS CS+ * Klipsch RF7s f>s>

Psalm 122:6f>c>s>

This message has been edited by deang on 06-23-2002 at 06:06 PM

[tpg]

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[Deang]

The speaker determines the impedence.

Most receivers are rated for 8 ohm speakers.

The situation with a multi-channel receiver is a little different. There are 5 separate and distinct amplifiers inside, and each is designed to run a set of 8 ohm speakers.

f>s>

------------------

Deanf>s>

AE-25 Super Amp DJH * S F Line 1 * S9000ES * HSU x-over * SVS CS+ * Klipsch RF7s f>s>

Psalm 122:6f>c>s>

[tpg]

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[Deang]

Well, as recently as six months ago I would have said you can never have too much power, and then I got sucked into this tube thing.

Still, more speakers are blown by having to little power than too much. This is because a lower powered amp will go into clipping sooner and clipping will destroy a tweeter right quick. With more power, you have more headroom and can avoid clipping.

Notice the KG 2.5's take 375 watts peak. The peak rating is closer to what music actually does. It goes up, it goes down -- the input signal is never 'continuous'. It would be tough to get 375 watt peak with a 75 watt reciever.

So, you got these pretty nice speakers. You are probably going to want to do HT and multi-channel sound. More power would be good, but more power costs more money, and you are on a budget.

Also, you need to know that not all watts are created equal. It's an odd principle to explain, but a receiver using discrete outputs instead of IC op amps will sound better and have more headroom for any given power rating.

I would take 40 watts of Onkyo or Sony ES over 100 watts of Pioneer or JVC. I still think NAD comes to the top as far as receivers go.

Why don't you buy a used unit. You can save big time money and get more receiver?

You posted this in the 2-channel forum. Are you doing the HT thing with your next reciever and multi-channel sound?

How about a 2-channel receiver with a 4 ohm rating so you can stack those babies and make some noise.

f>s>

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Deanf>s>

AE-25 Super Amp DJH * S F Line 1 * S9000ES * HSU x-over * SVS CS+ * Klipsch RF7s f>s>

Psalm 122:6f>c>s>

This message has been edited by deang on 06-23-2002 at 08:17 PM

[Deang]

Check these out. You can probably talk them down.f>s>

http://cgi.audiogon.com/cgi-bin/cl.pl?miscrcvr&1029691234&class&3&4&

http://cgi.audiogon.com/cgi-bin/cl.pl?miscrcvr&1029421997&class&3&4&

http://cgi.audiogon.com/cgi-bin/cl.pl?miscrcvr&1028928142&class&3&4&

http://cgi.audiogon.com/cgi-bin/cl.pl?miscrcvr&1027876203&class&3&4&

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Deanf>s>

AE-25 Super Amp DJH * S F Line 1 * S9000ES * HSU x-over * SVS CS+ * Klipsch RF7s f>s>

Psalm 122:6f>c>s>

This message has been edited by deang on 06-23-2002 at 08:27 PM

[tpg]

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[mobile homeless]

Dean, it's the type of power as well. Also, the way an amp handles clipping. The quality Single-Ended Triode amp handles clipping better than most designs. Low power can provide tremendous sonics when implemented correctly. I have heard no triode wired pentode come near a directly heated triode amp in purity, detail, openness, without stepping on musicality and creeping into HIFI.

kh

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Phono Linn Sondek LP-12 Valhalla / Linn Basic Plus / Sumiko Blue Point

CD Player Rega Planet

Preamp Cary Audio SLP-70 w/Phono Modified

Amplifier Welborne Labs 2A3 Moondog Monoblocks

Cable DIYCable Superlative / Twisted Cross Connect

Speaker 1977 Klipsch Cornwall I w/Alnico & Type B Crossover

system one online / alternate components / Asylum Listing f>s>

[Deang]

What in tarnation is a triode wired pentode? Let me guess -- my AE-25?

Hey, you know what I just found out? The DJH version of the Super Amp is class A/AB. What's up with that?

f>s>

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Deanf>s>

AE-25 Super Amp DJH * S F Line 1 * S9000ES * HSU x-over * SVS CS+ * Klipsch RF7s f>s>

Metal drivers make metal music shinef>c>s>

[mobile homeless]

Dennis probably configured this amp to slide into AB mode to achieve higher power ratings.

Hey Dean ole boy, one day you're going to try a quality vintage amp and go....

Ohhhhhhhh.

Heh...

Or attemp the SET route and never be the same.

kh

------------------

Phono Linn Sondek LP-12 Valhalla / Linn Basic Plus / Sumiko Blue Point

CD Player Rega Planet

Preamp Cary Audio SLP-70 w/Phono Modified

Amplifier Welborne Labs 2A3 Moondog Monoblocks

Cable DIYCable Superlative / Twisted Cross Connect

Speaker 1977 Klipsch Cornwall I w/Alnico & Type B Crossover

system one online / alternate components / Asylum Listing f>s>

[mike stehr]

Anyone have much exposure to any 6BQ5 SE amplifiers?

[mobile homeless]

Quite a few have. The infamous Decware ZEN amp is very close to a EL-84 single-ended application. IT relies on the Svetlana SV-83 tube which is very close. EL-84 can be used in this amp. There have been a host of EL-84 based SET offerings (these are not true Directly Heated Triode amps as they are pentodes connected in triode).

You will find some very good things here but you WONT find a lot of power. In fact, you will be lucky to get 1.5w from these beasts. You will need EXTREMELY sensitive speakers here, and even then, many find the EL-84 SET to not have enough.

Audio Note does a few designs with the EL-84 run in Parallel SET configuration. I dont think the EL-84 SET compares favorably with the 2A3, 300B, 45 or any of the true triodes though. They do some things VERY well however. But limitations are realized earlier.

kh

------------------

Phono Linn Sondek LP-12 Valhalla / Linn Basic Plus / Sumiko Blue Point

CD Player Rega Planet

Preamp Cary Audio SLP-70 w/Phono Modified

Amplifier Welborne Labs 2A3 Moondog Monoblocks

Cable DIYCable Superlative / Twisted Cross Connect

Speaker 1977 Klipsch Cornwall I w/Alnico & Type B Crossover

Links system one online / alternate components / Asylum Listing f>s>

[tpg]

.

[mike stehr]

Okay, So I visited the local audio guy I met in town here last Saturday.

He has this SE El-84 2 channel integrated amp, he was listening to this alone when I showed up.

We are guessing it is some Japanese vintage.

We test out some tubes, I get some caps and some Bugle

Boy 6DJ8's, and a Mullard 12AX7 to go with the one I have.

Then he breaks out his breadboard and his tube power supply and we proceed to listen to a whole box or two of tubes.

He has various output trannies on this breadboard, but he just used a (Sholtz?!!) brand trannie.

We listened to a Marconi ST 45, a Cunningham 45, A Sovtek EF-86? I think, I dunno, we listened to so many tubes I forgot half of them.

I don't remember any black plate RCA 2A3 tubes, but he had a pair of USN 2A3's (A GT tube with a lighter brown bakelight bottom), this 2A3 sounded NICE.

It had a nice sweet top end kinda like the 45's.

He had some other 2A3's we compared them to, but I can't remember what brands.

I think that Sovtek was a Pentode, I dunno.

Bottom line all tubes have thier own little signature of sound, IMO.

I would guess the tube's I remember are most favored.

Yes, granted this was a breadboard amp and wasn't no boutique gear, but you still get a pretty good idea of what these tubes sound like.

After this box of tubes, he mentioned that we will listen to the EL-84 SE before I leave.

That little SE EL-84 amp is right up there with all those tubes we listened to.

(He bypassed the volume and tone circuits and regapped the trannie, BTW.)

Yes, you do need some really sensitive speakers.

He has some english 10 inch fullrangers, Whiteley?

(I think.)

I have no clue how much wattage we were listening to with this amp, but it had plenty of power and bass without a pre-amp.

On those speakers however.

It made my Eico's sound like solid state, but that's my opinion.

I think Eico and Klipsch seem to work well together.

My mono Eico's sound pretty damn good on my Chorus II's, but didn't fair to well on his speakers.

I think SE EL-84 done right, compares favorably to triodes.

But there is something about no feedback that I seem to really favor.

I'm confused.

TPG,

A 100 watt reciever would be probably fine, just make sure it's not too cheap.

THANX!

This message has been edited by mike stehr on 06-25-2002 at 10:37 PM

[mobile homeless]

Do you realize how different that same 2A3, 45, 300B, 6BQ5 tube will sound when run at different operating points and in different circuits? To say you cant get a handle on which tube sounds the best via this kind of test is really problematic.

Wander over to the DIY Tube Asylum or the SET Asylum and read up on EL-84 SE use and you will see plenty of experimentation. Yes, it can sound very nice. But if you say the EL-84 compares favorably with true triode tubes like the 300B/45/2A3 when run in SE format then you are in a very, very small minority, a minority that is usually lead by manufacturers of EL-84 SE amps. Yet, there are some great SE 6BQ5 amps out there, many better than the ZEN.

Indeed, the EL-84 is one of my favorite tubes. In fact, I like it better now than my previous favorite EL-34 for pentode. However, I dont think I would ever go so far as to say the EL-84 compares favorably to triode tubes like the 2A3/45 in SET amps. While you might be able to optimize the EL-84 in an amp and have it sound better than a poorly used 2A3, given both at their best, I think the 2A3 comes out ahead.

But almost any tube can be made to sound quite nice if run in a circuit that is excellent and in it's sweet spot. These kinds of tests are very misleading because you can rarely pick up the countless variables.

kh

ps- In general, SET configuration will sound more open, more alive, and more magical then even the very best pentode configured amp, even when wired in triode. I will say that with your EICOs, I have found that I tend to prefer the EICO optimized as a whole unit. That being said, when you take the Single ended configuration and compare it to most pentode or triode wired push pull, you will favor the SE if run within its zone (and the zone widens considerably with different amps and within the right set up). No feedback via the SE amp is REALLY preferred for superior sonics. In general, I have always preferred amps, when they have this capability, switched in no feedback mode.

Phono Linn Sondek LP-12 Valhalla / Linn Basic Plus / Sumiko Blue Point

CD Player Rega Planet

Preamp Cary Audio SLP-70 w/Phono Modified

Amplifier Welborne Labs 2A3 Moondog Monoblocks

Cable DIYCable Superlative / Twisted Cross Connect

Speaker 1977 Klipsch Cornwall I w/Alnico & Type B Crossover

Links system one online / alternate components / Asylum Listing f>s>

This message has been edited by mobile homeless on 06-26-2002 at 05:59 AM

[mobile homeless]

T-guy, it is not the amount of power but the quality of power and the use and implementation. On the whole, I think less power done well tends to sound better than more power but, once again, this all relies on implementation and the circuit. There were more mediocre 100 watt solid state receivers made than anything in existance. And 200w of the same circuit, parts, and implementation can even sound worse, depending. There are so many variables here it is hard to draw conclusions. Higher wattage can potentially sound more effortless, especially if done well. But it is far easier to do a sublime 20w amplifier than a sublime 200w amplifier. Again, it is hard to talk in generalizations here. The quality of the watt is far more important on the whole, however.

When moving into the upper end of amplifiction, I have found less watts to actually surpass high wattage if trying to get within the performance and touch the emotional content. AGain, however, the implementation is all important, as well as the use. Pearl Harbor done on a 1.5w 45 amp is not going to push the home theater crowds' buttons.

This is a complex topic that would be hard to cover in 30 posts... And the answer is really dependent on your speakers sensitivity, impedance, listening tastes, room variables, etc. But power is always a complex subject. The great thing about easy to drive, high sensitivity speakers is that you dont NEED the power, which tends to corrupt, just as in other ways...

kh

This message has been edited by mobile homeless on 06-26-2002 at 05:51 AM

[tpg]

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