Mazeppa1

I'm running a horizantal bi-amp using the onboard passive crossover network of my Quartets. Grant Fidelity TubeDAC tube out > TK2050 T-amp > mid/high section of onboard mid/high passive crossover section. Grant Fidelity TubeDAC opamp out > Soundcraftsmen A2502 MOSFET amp > woofer section of onboard passive crossover section. Improvement over either output to a single amp to all passive crossover sections was dramatic. Improvement over either output to both amps in the above described scheme was significant. Oh, digital to the TubeDAC is an older SONY DVD player. I'm very pleased with my system as is, I mean it sounds really good. I can't bring myself to turn it off sometimes, but...... I keep reading, in various forums, so many threads extolling the virtues of active crossovers that I'm having a hard time resisting the temptation to pick up a Behrenger DCX and going full monte. My passive scheme was so successful, but active seems to hold even more potential for mo' betta sound. I may get the credit card warmed up - again. However, I'm intimidated by the prospect of setting the thing up w/o having to get into the whole room EQ software analysis rigamarole (this is where my interest begins to fade) as my system makes me grin as it is. Then there's the unbalanced/balanced thing to deal with as well. All my present equipment is unbalanced only. Still on the fence, here.

Same here using a hifimediy.com TK2050, 80(?)W T-amp. Just didn't have the oomph to get the bass out of my Quartets, but the top end was so nice I was inspired to try a passive bi-amp scheme. It was very straightforward to split the woofer section out from the crossover to another pair of binding posts. Pulled out my trusty Soundcraftsmen A2502 to feed the woofers Both amps have input attenuators, so SPL balancing was easy. It would be an understatement to say I was happy with the result, more like plumb giddy. My system bangs with authority or warbles oh so sweetly and everything in between depending on what it's fed. That was maybe 4-5 months ago, but wait - there's more. Since then I've gone from a homebrew tube-out DAC and Emotiva USP-1 preamp to a Grant Fidelity TubeDAC 09 set up with the volume pot controlling the line outs. At first I was running off the tube out to both amps and didn't notice much difference from my homebrew DAC , on which by now I had installed a volume/balance control and running it straight to the amps. The TubeDAC has an opamp line out as well, I wonder what'll happen if I run the woofer amp from there...... Hot damn! You talk about uptight and outtasite bass? I've got it. I'm unsure how this can help the mid/high section sound better, but it sure seems to. Sound is verrrry good from top to bottom, hard to turn off. Just can't seem to leave well enough alone, though. I'm presently working on a stereo 2-way active crossover built on a an Elliot Sound Products board for a hybrid active/passive crossover scheme.......... Still at it in Harrison, AR.

Wound up trying the T1 amp board (80W x 2 @ 8ohm) and have found the above stated doubts about good bass performance proved to be true. Pretty lame on the low end. The squawker and tweeter sounded so good, very smooth and detailed w/o any harshness or listening fatigue, that I moved up a plan to bi-wire the Quartets. The little T1 pushing the mids/highs, and a Soundcraftsmen A2502 (125W x 2 @ 8ohm, 190W x 2 @ 4ohm) pulling woofer duty. The combination is working very well, really brings the magic out of a well recorded cd such as the MoFi "Dixie Chicken" by Little Feat for instance. While by no means a stand alone, giant killer, the little T1 Tripath from Hifimediy is very, very good within its power limitations.

kg 2.2 ad forte 2 measure 5.0ohm resistance. I cant measure impedance. that varies with v and fq. impedance drops well below 4 at low freq this is the cheap amp worth trying you may have seen thread already http://www.audiocircle.com/index.php?topic=76400.360 cheap amp and good bass is VERY difficult to achieve/find I rather suspected that my Quartets (little brother to your Forte II) may well drop to a rather low impedance at low freqs. Of the two I listed, the 4/8 ohm amp is probably the better choice then. However, the amp in the thread you mentioned cetainly seems to be well thought of. Quite a bit more power, and USA origin, very interesting, Thanks for the tip and impedance info.

I don't think you are quite getting it. The little class D amps you listed are around 20 watts @8 ohms with little or no headroom, weak power supplies and no storage capacity (big caps). In other words they are a weak 20 watts, not what you are looking for. Some of the mass consumer level receivers are rated at 100 watts a channel and suffer from the same problem, no guts. My 15 watt tube amps blow them away. Try a GOOD amp sometime and you will hear the difference a quality amp makes. Happy hunting. The listing links in my original, messy post are a bit difficult to pull out so here they are again: http://cgi.ebay.com/TK2050-Hifimediy-2-80W-CLASS-T-TRIPATH-T-AMP-Board-ALPS-/130406075583?pt=LH_DefaultDomain_0&hash=item1e5cceccbf#ht_1821wt_932 http://cgi.ebay.com/TK2050-Hifimediy-V2-0-2-100W-4ohm-Meanwell-27V-350W-/130410496357?pt=LH_DefaultDomain_0&hash=item1e5d124165#ht_1512wt_932 The second listing now includes the power supply recommended for both boards which is a 350w, 27vdc unit. I'm not sure if I'm sold on a switching type power supply, but note the rating. These are not complete amps, but amp boards to be assembled into an amp. They may be more comparable to the consumer level receivers rated @ 100W you mention, but I think they could be much better. A lot of guys over diyaudio seem to think so. If you don't mind me asking for the particulars of your system? 1. Amp type (SET, PP) and make, power supply capacity,how connected to speakers (multiple taps on output? if so, which used?)? Comments on low impedance load handling capability. 2. Speaker model, nominal impedance. My understanding is that actual impedance presented by a speaker to an amp varies w/frequency and that some speakers dip lower from nominal than others in use. What I'm trying to figure out here is if in spite of the nominal 8 ohm impedance rating of my Quartets, might they be better served by use w/an amp capable of working well w/6 or 4 ohm nominal impedance loads? The Class D amps seem to be bit load sensitive is why I'm trying to narrow this thing down as closely as I can. BTW, I'd love to try a good tube amp, but it's not in the cards for me quite yet.

Gotcha, carriage return prob is Chrome related. Using Explorer for this post, we'll see how that goes. Not really amp shopping, just got curious about the Class D's. My understanding is that their output is usable up to about 50% of rated power before THD reaches objectionable levels. The boards I'm looking at are rated 80WPC & 100WPC, so 40WPC & 50WPC usable can be expected. The HK 330c (15WPC) sounds wonderful w/the Quartets for 90% of my music listening, but falls short when I want to get get really loud. The Soundcraftsmen (+ Emotiva pre) has more than enough power, but sounds good w/the Quarts, not wonderful. Are you running an Onkyo A-9555? Which speakers?

Thanks for the reply, but I'm using a Dell PC + Google Chrome. Maybe I should try Explorer?

As can be seen this is my first post. Would someone tell me how to get line spaces to transfer from the draft to the actual posting?

Hey y'all. I've got the bug to try a Class D amp with my Quartets, and could use help in choosing between these two: http://cgi.ebay.com/TK2050-TP2050-2-100W-CLASS-T-D-TRIPATH-T-AMP-Board-/130397808636?pt=LH_DefaultDomain_0&hash=item1e5c50a7fc#ht_1737wt_1139 http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=130406075583&ssPageName=STRK:MEWAX:IT#ht_1701wt_1139 A little background info. My Quartets have the Crites cap kit, autotransformer and titanium tweeter diaphragm in them. As can be seen in the listings, one is recommended for 8 ohm (T1) speakers, the other for 4/8 ohm (T2). I've read several posts on other forums that confirm the vendor's recommendations. So you say, "Quartets are rated 8 ohm nominal, doesn't that answer the question?" It would except that I have read that some tube amp guys running Forte's have had very good results when changing to the 4 ohm taps on their amps. Plus, the SS amps that I've tried w/my Quartets that sound the best to me are ones that are known to handle low impedance loads well ( HK 330c and Soundcraftsmen A2502). Soooo, can it be that these series of Klipsch often dip to fairly low impedances in actual use, and the 4/8 ohm (T2) amp listed above be the best choice? I'm leaning that way, but would value any comments/opinions from the forum members regarding this question as audiobux are getting harder to come by and I'd like to make the most informed decision possible. "Turn it up!" - Lynryd Skyrnyrd