novisnick
EmoPhile
CEO Secret Monoblock Society
Posts: 27,223 
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Post by novisnick on Apr 28, 2014 23:49:27 GMT -5
Or did I miss something again?  ? Ya know at times I miss stuff. Me too Yep, im learning all the time. No you didnt quote me,,,,,,,,,, Yep, Im learning all the time. Did you miss my pair of XPR-1s? They realy are , all that and a cup of butter. : ) I was just noting that the recomendation of the bridged XPA-2 was 8 ohms only,,,,,,no I havnt seen an amp with multi- taps for different rated speakers. Did I mention that I miss stuff and that Im learning,,,,,he,,,,,he,,,,,, Thanks for the info,,,,,and yes Im having fun as well! After all,,,life is way too short not to enjoy the trip. Always enjoy your posts Gary, its late and I have to get my BEAUTY sleep,,',,,,,,he,,,,,,he,,,,,,,,,Il need to sleep a long time to get any benefits from that. Nick |
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Post by deltadube on Apr 28, 2014 23:49:40 GMT -5
nothing like membership in the monoblock society Gary!!! you can vertical bi amp an xpa 2 but it still wont be a fully balanced quad differential signal!!!!! if you use the xpa 1 with its quad binding post very easy to use 2 sets on speaker cables as well and no rca y adapter needed to save some cash!!! the big power reserves of the xpa 1 and the quad differential signal path is by far superior to the xpa 2 imho.. cheers So in order to be classed as a monoblock it has to be "fully balanced quad differential"? Does that mean that an XPA-100 isn't a monoblock? Or does it mean that an XPA-1 with input via RCA's is no longer a monoblock as it's not using its "fully balanced quad differential" circuitry?
Power reserves I dealt with in the post above, one example was an XPR-2 which arguably has more "power reserves" than an XPA-1, does that make it a "better" monoblock?
Cheers Gary
Gary what are you yacking about ... it makes no sense to what I wrote.. xpa 1 is by far superior too xpa 2 and xpr 2.. |
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Post by Gary Cook on Apr 28, 2014 23:53:18 GMT -5
Or did I miss something again? ? Ya know at times I miss stuff. Me too Yep, im learning all the time. No you didnt quote me,,,,,,,,,, Yep, Im learning all the time. Did you miss my pair of XPR-1s? They realy are , all that and a cup of butter. : ) I was just noting that the recomendation of the bridged XPA-2 was 8 ohms only,,,,,,no I havnt seen an amp with multi- taps for different rated speakers. Did I mention that I miss stuff and that Im learning,,,,,he,,,,,he,,,,,, Thanks for the info,,,,,and yes Im having fun as well! After all,,,life is way too short not to enjoy the trip. Always enjoy your posts Gary, its late and I have to get my BEAUTY sleep,,',,,,,,he,,,,,,he,,,,,,,,,Il need to sleep a long time to get any benefits from that. Nick It's only 3 o'clock in the afternoon here, I'm just warming up, nearly time for a glass of red  Cheers Gary |
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novisnick
EmoPhile
CEO Secret Monoblock Society
Posts: 27,223
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Post by novisnick on Apr 28, 2014 23:54:35 GMT -5
Blah,,,blah,,,,blah,,,,,buy a set of XPR-1s,,,,,,,,blah,,,,,,blah,,,,,,blah,,,,,,,,,
Blah,,,blah,,,,blah,,,,,buy a set of XPR-1s,,,,,,,,blah,,,,,,blah,,,,,,blah,,,,,,,,,
Blah,,,blah,,,,blah,,,,,buy a set of XPR-1s,,,,,,,,blah,,,,,,blah,,,,,,blah,,,,,,,,,
Blah,,,blah,,,,blah,,,,,buy a set of XPR-1s,,,,,,,,blah,,,,,,blah,,,,,,blah,,,,,,,,,
Blah,,,blah,,,,blah,,,,,buy a set of XPR-1s,,,,,,,,blah,,,,,,blah,,,,,,blah,,,,,,,,,
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Post by Gary Cook on Apr 29, 2014 0:18:24 GMT -5
Continuing the education............. I havnt seen an amp with multi- taps for different rated speakers.
Multiple impedance taps are most commonly found on transformer coupled tube amps. I was doing a bit of rewiring on an Onix SP3 a couple of weeks ago, it's a stereo amp with 4, 8 and 16 ohm outputs.
Cheers Gary |
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Post by Gary Cook on Apr 29, 2014 0:19:47 GMT -5
Blah,,,blah,,,,blah,,,,,buy a set of XPR-1s,,,,,,,,blah,,,,,,blah,,,,,,blah,,,,,,,,, Blah,,,blah,,,,blah,,,,,buy a set of XPR-1s,,,,,,,,blah,,,,,,blah,,,,,,blah,,,,,,,,, Blah,,,blah,,,,blah,,,,,buy a set of XPR-1s,,,,,,,,blah,,,,,,blah,,,,,,blah,,,,,,,,, Blah,,,blah,,,,blah,,,,,buy a set of XPR-1s,,,,,,,,blah,,,,,,blah,,,,,,blah,,,,,,,,, Blah,,,blah,,,,blah,,,,,buy a set of XPR-1s,,,,,,,,blah,,,,,,blah,,,,,,blah,,,,,,,,, Too bad they aren't available for shipment to Australia  Cheers Gary |
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Post by deltadube on Apr 29, 2014 1:09:27 GMT -5
Or did I miss something again? ? Ya know at times I miss stuff. Me too Yep, im learning all the time. No you didnt quote me,,,,,,,,,, Yep, Im learning all the time. Did you miss my pair of XPR-1s? They realy are , all that and a cup of butter. : ) I was just noting that the recomendation of the bridged XPA-2 was 8 ohms only,,,,,,no I havnt seen an amp with multi- taps for different rated speakers. Did I mention that I miss stuff and that Im learning,,,,,he,,,,,he,,,,,, Thanks for the info,,,,,and yes Im having fun as well! After all,,,life is way too short not to enjoy the trip. Always enjoy your posts Gary, its late and I have to get my BEAUTY sleep,,',,,,,,he,,,,,,he,,,,,,,,,Il need to sleep a long time to get any benefits from that. Nick It's only 3 o'clock in the afternoon here, I'm just warming up, nearly time for a glass of red Cheers Gary drinking is not much an excuse Gary... your xpa 100 will only get you a jr membership in the monoblock society  need to have a pair of quad differential fully balanced mono blocks for senior membership with full benefits... cheers eh.. |
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Post by Gary Cook on Apr 29, 2014 1:58:40 GMT -5
It's only 3 o'clock in the afternoon here, I'm just warming up, nearly time for a glass of red Drinking is not much an excuse Gary... Your xpa 100 will only get you a jr membership in the monoblock society need to have a pair of quad differential fully balanced mono blocks for senior membership with full benefits... cheers eh.. I haven't started drinking yet, still have a couple of hours of work to do  I've been considering a pair of XPA-1L's for while, they're fully balanced, fully discrete and quad differential. Might see if the Gen 2's are worth the extra over the Gen 1's. To be totally truthful I couldn't care less if my amps are fully balanced, fully discrete or quad differential as I've never been able to hear any difference with my ears using my speakers in my room. Cheers Gary |
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Post by boomzilla on Apr 29, 2014 2:25:24 GMT -5
...To be totally truthful I couldn't care less if my amps are fully balanced, fully discrete or quad differential as I've never been able to hear any difference with my ears using my speakers in my room. Cheers - Gary And again, Mr. Cook is completely correct! The advantages of fully balanced, fully discreet, and quad differential are certainly there theoretically. Does it mean that those advantages are actually audible? I guess it varies with the listener. One can claim the technical superiority of the Xxx-1 amps over the Xxx-2 ones until the cows come home. Unless I can hear the difference, though, it isn't worth any extra $$ to me. |
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Post by deltadube on Apr 29, 2014 2:43:36 GMT -5
...To be totally truthful I couldn't care less if my amps are fully balanced, fully discrete or quad differential as I've never been able to hear any difference with my ears using my speakers in my room. Cheers - Gary And again, Mr. Cook is completely correct! The advantages of fully balanced, fully discreet, and quad differential are certainly there theoretically. Does it mean that those advantages are actually audible? I guess it varies with the listener. One can claim the technical superiority of the Xxx-1 amps over the Xxx-2 ones until the cows come home. Unless I can hear the difference, though, it isn't worth any extra $$ to me. boomer you can hear a difference its like night and day eh... you will never get into the monoblock society with that attitude... you have to pay up to hear the difference you know... no mono blocks for sale at the local garage sale? cheers |
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Post by boomzilla on Apr 29, 2014 2:57:53 GMT -5
In fact, I've heard numerous mono blocks in my system, including:
VTL Compact 100 tube amplifiers
Quicksilver tube amplifiers
Emotiva XPR-1L amplifiers
Marantz MA500 amplifiers
Nelson Pass amplifiers
They've all sounded fine, but not that different to my ears than equivalent stereo amplifiers. The only stereo amplifiers that I've tried in vertically bi-amplified mode are the Crown PS400s. They were superior with some speakers, but not with others.
I'm personally convinced that the synergy (or lack of) between the amplifier and speaker makes more difference to the sound than the particular circuit topology. My DefTech SM65 speakers, for example, were slightly dull sounding in the treble with most amplifiers, but the Crown PS400 amps, being a bit more dynamic in that range than most, worked very well with the DefTechs. My current Technics by Panasonic speakers really like the laid-back sound of the XPR-2 amplifier. And so it goes... Since amplifiers are both physically small and relatively inexpensive compared to speakers, it seems to me that amplifiers are the things to swap in and out until one finds a good match to the preferred speakers.
Others may choose otherwise, but with the amps that I have in house, I can usually find at least one to match just about any speaker pair. I may, one day, go for some used mono block amps again, but I'm seriously doubting it at this point.
Boom
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KeithL
Administrator 
Posts: 9,929
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Post by KeithL on Apr 29, 2014 10:10:38 GMT -5
A "monoblock" just means that it's a one-channel power amplifier.... of course there are different "levels" of monoblocks  In general, you do want to avoid loads below 8 ohms with the XPA-2 in bridged mode.... (But we specifically tell you not to use it that way with 4 ohm speakers because sometimes they go down to two or three ohms. An "8 ohm" speaker that dips down to 3.7 ohms at only one place wouldn't be a problem.) In your specific situation, though, using both channels in a vertical-biamp configuration is probably going to get you more overall performance than bridging the amp, and then NOT bi-amping it. nothing like membership in the monoblock society Gary!!! you can vertical bi amp an xpa 2 but it still wont be a fully balanced quad differential signal!!!!! if you use the xpa 1 with its quad binding post very easy to use 2 sets on speaker cables as well and no rca y adapter needed to save some cash!!! the big power reserves of the xpa 1 and the quad differential signal path is by far superior to the xpa 2 imho.. cheers So in order to be classed as a monoblock it has to be "fully balanced quad differential"? Does that mean that an XPA-100 isn't a monoblock? Or does it mean that an XPA-1 with input via RCA's is no longer a monoblock as it's not using its "fully balanced quad differential" circuitry?
Power reserves I dealt with in the post above, one example was an XPR-2 which arguably has more "power reserves" than an XPA-1, does that make it a "better" monoblock?
As for "saving some cash" an XPR-2 costs less than 2 x XPA-1's 
Cheers Gary
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KeithL
Administrator
Posts: 9,929
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Post by KeithL on Apr 29, 2014 10:22:44 GMT -5
Exactly correct. Tube amps need to use an output transformer anyway, so adding multiple impedance taps is rather trivial. McIntosh also included output transformers on many of their solid state models (and so they also had multiple impedance taps). In general, though, solid state amps do NOT use transformers - because the disadvantages of transformers far outweigh (and, yes, that's a sort of a pun there ) the advantages. When you bridge an amp, each of the two original channels sees HALF of the load impedance... so, when you put an 8 ohm speaker on a bridged amp, each channel sees a 4 ohm load - which is fine. However, if you put a 4 ohm speaker on a bridged amp, each channel sees a 2 ohm load - which is too low for most amps. Continuing the education............. I havnt seen an amp with multi- taps for different rated speakers.
Multiple impedance taps are most commonly found on transformer coupled tube amps. I was doing a bit of rewiring on an Onix SP3 a couple of weeks ago, it's a stereo amp with 4, 8 and 16 ohm outputs.
Cheers Gary |
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Deleted
Deleted Member
Posts: 0
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Post by Deleted on Apr 29, 2014 10:50:02 GMT -5
Bob..Novi!...I see you guys are still kicking it around?..and Big Kieth still keeping everyone on the right track..Sorry I been out of the loop but I am in the middle of "cleaning" up a few last things in my life. should all be done in the next few months.My Son Adrian has done some wonderful things with all the gear I sold him..I hope he comes in here and open an account to share with everyone. He is totally loving his EMO gear, plus I learned a lot from him.. like inputting a "EQ" in the loop alone with the Parasound 2100 he has them LSi's sounding better than I ever could get them too sound, well they sound like "Audiofile" speakers should now. Maybe I should have read a lil more up on setting gear up?..lolo that's what I get for being too "old school" two channel guys are a little too old school sometimes. Rock on Bros!
Mike
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Post by leonski on Dec 27, 2014 4:20:39 GMT -5
2 DPOLMAN:
I run a PAIR of Parasound amps with my Maggies. They are setup for easy biwiring or biamping. However, I don't consider it biamping when you still have the speaker level crossover involved. Follow this: When you remove the speaker level crossover AND add a Line Level crossover BETWEEN the amp and preamp, you can gain as much as 3db in amp power. That's like DOUBLE the amp power. Your amps are currently called upon, as are mine, to deal with 'out of band' signals which take power for NO audible benefit.
My goal is to DELETE the speaker level crossover and connect EACH driver to its OWN amp. Between the amp(s) and preamp will be a crossover. And in doing my homework, I find I have a choice of 2 major types. The 'Passive' requires knowing the input and output impedance of the connecting gear and SHORT cable runs. The 'Active' crossover is generally opamp driven doesn't care too much about the impedance of anything AND can drive a longer run of cable. BUT, you need a very good (quiet) power supply and more engineering. Kits are available. Personally? I'm going passive. I can EASILY duplicate my speakers transfer function and locate the crossover right AT the amp. The run FROM the pre is no problem at <8 feet a side. Also, most active crossovers can be as great as 24 db/octave which I've never heard anything GOOD about, except maybe as a sub crossover. I'm not about to Re-Engineer and second guess the guys that designed and built my Maggies.
And Keith, Mc uses AUTOFORMERS on many SS amps. NOT transformers, as you correctly noted. If anyone cares, I'll do a little writeup on the Differences between 'em…….
If I remember correctly, Carver had an amp with both Current Source (similar to tube amps) and Voltage Source (the ideal SS amp) which basically inserted some additional resistance into the line. Some speakers Prefer one or the other.
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Post by moko on Dec 27, 2014 7:02:41 GMT -5
hi leonski, i can see that article about bi-amping has create a lot of confusions between bi-ampers. i believe that in figure 1 of that article about removing the passive crossovers in woofers is MAINLY to give the amps more easy load and more power to spare. what the article doesn't explain is that the RC (resistor-capasitor) circuits in the woofer's passive crossovers as part of low pass filter ARE the ones responsible for phase shift which can create big phase angle. this big phase angle at low frequencies is the one who makes amps suffer. so it is a benefit to remove passive crossover in the woofers, especially for small amps who cannot handle heavy load. BUT it also has disadvantages : 1. we have to guess the crossover frequency and the slope. not an easy task. guessing it wrong makes the speakers sound different. 2. if the low pass filter also include a notch filter (an LCR circuit maybe around 100 hz) to reduce the boominess, most active crossovers can't do that. 3. most woofers have break up frequency where the higher frequencies are peaking like hell. this also need a notch filter otherwise the midrange will suffer. so i agree with you about keeping the low pass filter in the woofer untouched. |
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Post by leonski on Dec 27, 2014 13:22:21 GMT -5
Yes, the 'big phase angle' is reactance. The speaker WITH its crossover looks like a capacitor or inductor to the amp. And various levels of either as the frequency changes. A line level crossover, one defined as being between the amp and preamp can net you as much as 3db additional power, based on the amps no longer having to reproduce 'out of band' signals. So, the bass amp now only is FED bass and nothing else to amplify. I'm heading that way right now. I'm working on a PASSIVE line level crossover which is just Caps and Resistors on a very small board. No OpAmps or other parts needing power. If you want to go Cost No Object for a crossover, Pass Labs makes the B5 which is $$$ but incredibly flexible. Here is an Article from Pass dealing with crossovers and the phase / amplitude issues raised by them. Pretty geeky, and detailed, but if you cherry pick, you can get some real nuggets. passlabs.com/articles/phase-coherent-crossover-networkswww.firstwatt.com/pdf/prod_b5_man.pdfThe user manual for the B5 may help, too. And yes, those 'notches', impedance matching, Zobels, and the rest turn a crossover into a major electronics and research project. That's why I think that Magnepan is such a DIY dream speaker. Many people report good results just duplicating the original crossover transfer function and much debate exists over WHICH generation crossover to use. The MMG for example, has had a couple different crossovers over its long run. Something called a 'Series' crossover seems to get the most play. I think the really dedicated DIY person could eventually drive themselves nuts with this. The question of 'is it better or just different' plagues these kinds of projects I'd expect the real over-achiever to have everything from a signal generator to a scope and 2 or 3 GOOD DVMs. It is beyond a quick post like this, but the Least Expensive Radio Shack speaker a long time had JUST a cap for its 'crossover' The other driver ran full-range and rolled off at its 'natural' rate, while the tweeter had lows excluded to save the part from burning up! |
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Post by boomzilla on Dec 27, 2014 13:41:54 GMT -5
I've had good results with both vertical bi-amping and with mono blocks. Since you already have the stereo amp, I'd recommend vertical bi-amping first.
My results were also better with long interconnects & very short speaker cables.
Your mileage may vary...
Boom
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Post by leonski on Dec 27, 2014 15:12:28 GMT -5
Amp power per 'way' is VERY dependent on crossover frequency. If you crossover at say……5000hz, you may only need 20% to 25% of the TOTAL available power above the crossover, the rest below. Few speakers, especially 2-ways would have such a frequency as crossover.
Somewhat more meaningful would be the 50:50 point of ABOUT 350hz. My Panels cross over at 600hz and I LOW CUT them below about 60 or 70hz, so I'm very near 50:50 and DO run a stereo amp per speaker.
Another factor MOST people ignore is Amplifier GAIN. This should, as an ideal, be identical. Again, identical amps are the solution here.
And finally, TRUE BIAMP will NOT have a speaker level crossover except perhaps between the mid and tweet of a 3-way system. My buddy with Magnepan MG20s (Nice, true ribbon panels) uses a BIG EMO MONOBLOC for bass and a 100 watt tube MONOBLOC for treble. The 2-way crossover duties are handled by Marchand, which is a fairly pricey but complete solution. This crossover goes BETWEEN the preamp and the POWER AMP.
And BOY, does it work NICE. Amazing bass for a panel. It really digs deep with terrific articulation.
My solution for a 2-way will be a PASSIVE Line Level XO.
And YES, for sure. I run about 8 feet of Single Ended (RCA) per side and 2 runs of 4 feet EACH speaker wire (10 ga. Belden) per side. If I went MUCH further, maybe 12 feet or further, I'd use BALANCED and unfortunately a splitter. My amps have an IN / OUT loop, so I run ONE wire TO the amp and use a very short jumper from channel 'A' out to channel 'B' in. My amps have NO such provision for balanced. I also have level controls on EACH channel, but they are 'wide open' and therefore un used.
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Post by moko on Dec 28, 2014 0:12:12 GMT -5
the use of active crossover in that article is because the low pass filter is removed. with the low pass filter removed, the amp now has to deal with 'out of band' signals. that's why active crossover needed in that article.
so the bottom line is if you still have the low pass filter, then active crossover is not needed.
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? Ya know at times I miss stuff.
need to have a pair of quad differential fully balanced mono blocks for 
