A Man's Amp - Krell KSA-250
schwarcw
Posts: 7,338
This amp has a committed buyer from a good Polkie here on the forum. However, should the deal fall through and it becomes available I will update this post.
This pure Class A amp is a 140 lb 250 wpc monster. It will drive anything you own. This amplifier is a one owner amplifier that was used by Dipole Dan to drive the Carver Platinum MK IV's. It comes with the original box, packing materials, owners manual, etc.
According to Stereophile (1991):
The mother lode of Krell amplifiers has arrived, and its name is the KSA-250. If the KSA-50 had the weight of a steamroller, this one has the impact of an atomic bomb. Krell amplifiers have always been known for their superb stability and bass control, but have been, in my opinion, somewhat short in the department of musical finesse. Of course the KSA-100 and -200 and the KMA-80 and -160 were superb amplifiers, but there were competitors who gave up very little in the bass region and offered much more harmonic and musical honesty. In this respect, the KSA-250 is a landmark product for Krell; unquestionably their most refined amplifier to date, and possibly the most successful blend of solid-state and vacuum-tube virtues to come down the pike. No, it doesn't do everything perfectly, but in terms of overall sonics, and especially price/performance ratio, it's a winner.
Technical highlights
The KSA-250 is, without a doubt, the most visually appealing amplifier that Krell has yet marketed. Though large and very heavy, the presentation is one of stoic grace rather than imposing high-tech visual intrusion. The amplifier body is finished in flat black, with heatsinks externally lining both sides from front to back. The rear panel is neatly laid out, with single-ended phono sockets and balanced female XLR connectors on either side. Additionally, there are two sets of five-way binding posts for loudspeaker cable connections, which makes speaker bi-wiring a breeze. The front panel is finished in an elegant brushed-gray finish with large, black, attractive, downward-facing handles. The feather-touch power switch is located in the center of the front panel, just above the ubiquitous Krell logo. A blue LED power tally light is positioned just above the switch. All in all, a very nicely designed package.
Internally, the KSA-250 is a study in simplicity as well as a technological tour de force. The 4.5kVA transformer, which by itself weighs 85 pounds (!), is located just behind the front panel, and is in turn followed by four 47,000µF capacitors covered by a printed circuit board. It is important to note that there is no wiring in the signal path, all connections being made via the pcb in the front end, and gold-plated copper-beryllium busbars in the output stage. There are 24 output devices per channel, all operating in class-A mode down to 3 ohms, where the amplifier reverts to class-AB (see Sidebar 3). The KSA-250 utilizes class-A circuitry throughout the audio and power-supply regulation stages, and can actually generate 320Wpc into 8 ohms. It is DC-coupled throughout, without any capacitors in the signal path, and is a fully modular design employing gas-tight pressure connections between all subassemblies, allowing quick and easy servicing in the field.
According to Dan D'Agostinothe driving force behind every Krell productthe deletion of wiring within the signal path yields several benefits, including lack of coloration, long-term stability over many years (no possible oxidation or other internal wiring degradation), and reduced interaction between the output stage and external speaker wiring. Additionally, according to Dan, modular design and wireless direct internal connections produce far greater sample-to-sample consistency than was previously attainable.
This amp is like no other that you can find without spending $5K or more. SALE PENDING
This pure Class A amp is a 140 lb 250 wpc monster. It will drive anything you own. This amplifier is a one owner amplifier that was used by Dipole Dan to drive the Carver Platinum MK IV's. It comes with the original box, packing materials, owners manual, etc.
According to Stereophile (1991):
The mother lode of Krell amplifiers has arrived, and its name is the KSA-250. If the KSA-50 had the weight of a steamroller, this one has the impact of an atomic bomb. Krell amplifiers have always been known for their superb stability and bass control, but have been, in my opinion, somewhat short in the department of musical finesse. Of course the KSA-100 and -200 and the KMA-80 and -160 were superb amplifiers, but there were competitors who gave up very little in the bass region and offered much more harmonic and musical honesty. In this respect, the KSA-250 is a landmark product for Krell; unquestionably their most refined amplifier to date, and possibly the most successful blend of solid-state and vacuum-tube virtues to come down the pike. No, it doesn't do everything perfectly, but in terms of overall sonics, and especially price/performance ratio, it's a winner.
Technical highlights
The KSA-250 is, without a doubt, the most visually appealing amplifier that Krell has yet marketed. Though large and very heavy, the presentation is one of stoic grace rather than imposing high-tech visual intrusion. The amplifier body is finished in flat black, with heatsinks externally lining both sides from front to back. The rear panel is neatly laid out, with single-ended phono sockets and balanced female XLR connectors on either side. Additionally, there are two sets of five-way binding posts for loudspeaker cable connections, which makes speaker bi-wiring a breeze. The front panel is finished in an elegant brushed-gray finish with large, black, attractive, downward-facing handles. The feather-touch power switch is located in the center of the front panel, just above the ubiquitous Krell logo. A blue LED power tally light is positioned just above the switch. All in all, a very nicely designed package.
Internally, the KSA-250 is a study in simplicity as well as a technological tour de force. The 4.5kVA transformer, which by itself weighs 85 pounds (!), is located just behind the front panel, and is in turn followed by four 47,000µF capacitors covered by a printed circuit board. It is important to note that there is no wiring in the signal path, all connections being made via the pcb in the front end, and gold-plated copper-beryllium busbars in the output stage. There are 24 output devices per channel, all operating in class-A mode down to 3 ohms, where the amplifier reverts to class-AB (see Sidebar 3). The KSA-250 utilizes class-A circuitry throughout the audio and power-supply regulation stages, and can actually generate 320Wpc into 8 ohms. It is DC-coupled throughout, without any capacitors in the signal path, and is a fully modular design employing gas-tight pressure connections between all subassemblies, allowing quick and easy servicing in the field.
According to Dan D'Agostinothe driving force behind every Krell productthe deletion of wiring within the signal path yields several benefits, including lack of coloration, long-term stability over many years (no possible oxidation or other internal wiring degradation), and reduced interaction between the output stage and external speaker wiring. Additionally, according to Dan, modular design and wireless direct internal connections produce far greater sample-to-sample consistency than was previously attainable.
This amp is like no other that you can find without spending $5K or more. SALE PENDING
Carl
Post edited by schwarcw on
Comments
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My pants just came clean off.
BDTI plan for the future. - F1Nut -
Why do I salivate more when I see an amp like that than I do hot chicks?
That toroidal is huge!!!Please. Please contact me a ben62670 @ yahoo.com. Make sure to include who you are, and you are from Polk so I don't delete your email. Also I am now physically unable to work on any projects. If you need help let these guys know. There are many people who will help if you let them know where you are.
Thanks
Ben -
good grief man
:D how deep does it sit? two feet?? JC approves....he told me so. (F-1 nut) -
Dan
My personal quest is to save to world of bad audio, one thread at a time. -
Mine didn't even get a chance... damn, now I gotta change my draws....
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Audio **** baby.
Speakers
Carver Amazing Fronts
CS400i Center
RT800i's Rears
Sub Paradigm Servo 15
Electronics
Conrad Johnson PV-5 pre-amp
Parasound Halo A23
Pioneer 84TXSi AVR
Pioneer 79Avi DVD
Sony CX400 CD changer
Panasonic 42-PX60U Plasma
WMC Win7 32bit HD DVR -
Drats......I never knew!!!! That's what I need.
:( -
Could this drive Lsi7s?
I need an amp to power my surrounds
Stereo Rig: Hales Revelation 3, Musical Fidelity CD-Pre 24, Forte Model 3 amp, Lexicon RT-10 SACD, MMF-5 w/speedbox, Forte Model 2 Phono Pre, Cardas Crosslink, APC H15, URC MX-950, Lovan Stand
Bedroom: Samsung HPR-4252, Toshiba HD-A2, HK 3480, Signal Cable, AQ speaker cable, Totem Dreamcatchers, SVS PB10-NSD, URC MX-850 -
Holy crap that was fast... what was the price?Gallo Ref 3.1 : Bryston 4b SST : Musical fidelity CD Pre : VPI HW-19
Gallo Ref AV, Frankengallo Ref 3, LC60i : Bryston 9b SST : Meridian 565
Jordan JX92s : MF X-T100 : Xray v8
Backburner:Krell KAV-300i -
Carl, what's your oppinion on this amplifier and the carver amazings?
Is this amp a common ground amplifier? How well will this amplifier drive the 1.2 tl?SRT For Life; SDA Forever!
The SRT SEISMIC System:
Four main satellite speakers, six powered subs, two dedicated for LFE channel, two center speakers for over/under screen placement and three Control Centers. Amaze your friends, terrorize your neighbors, seize the audio bragging rights for your state. Go ahead, buy it; you only go around once. -
Yeah, unless I missed it I didn't see a price.... I guess if ya have to ask, ya can't afford, and I'm sure I couldn't. Still kinda like to know what the ballpark was.
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Yeah, unless I missed it I didn't see a price.... I guess if ya have to ask, ya can't afford, and I'm sure I couldn't. Still kinda like to know what the ballpark was.
It's a krell. You're not supposed to ask how much just how many zeros. SRT For Life; SDA Forever!
The SRT SEISMIC System:
Four main satellite speakers, six powered subs, two dedicated for LFE channel, two center speakers for over/under screen placement and three Control Centers. Amaze your friends, terrorize your neighbors, seize the audio bragging rights for your state. Go ahead, buy it; you only go around once. -
Hi Ed!
It is common ground. It will give the 1.2TL's a deep, detailed soundstage. No caps in the signal path, the sound is absolutely black. The torridal transformer is about 50% larger than two JC-1 monoblocks. Deep, tight bass. Some users felt the later model Krells were a little bright or detailed. Not this map. It will make a pair of swimmining pool speakers sound like Wilsons.
CarlCarl -
Better make sure you live on ground level with that piece! I could just see it coming crashing through a 2nd or 3rd floor apartment from the weight.....nice amp!
