Phase Linear with KHorns

[minn_male42]

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On 1/18/2005 7:55:52 PM triode wrote:

"i've had my ZR amp now for about a year and a half and haven't heard anything better!"

Given your history of the amps you've owned, I am sure you haven't!

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welcome to the forum newbie!

despite your sarcastic remark - i have heard many other amplifiers in my system as well as in other systems.

i've auditioned (in my system) or owned: dynaco, aragon, sherbourn, sunfire, parasound, rotel, NAD, and professional amps from qsc, samson, peavey, crest, and crown.

i have also auditioned in dealer showrooms or in friend's systems(although not all with klipsch speakers) gemstone, belcanto (very good), monster power, van alstine, krell, acoustic research (tube), plinius, and B&K.

and despite the fact that there are many very high quality amplifiers in the above list, i have not heard anything better than my carver pro ZR1000 digital amplifier in terms of detail, power, and smoothness..... you can find other amps that excel in smoothness, but lack the power needed for very dynamic music..... or amps that give you tons of power, but are harsh on the top end with klipsch speakers....

btw - care to share with us what you use to power your system and your vast experience with many different amplifiers????

[joessportster]

hello i am currently running 2 phase linear 400 amps with my cornwalls, and heresy's and have no complaints about the amps them selves , the pre-amps on the other hand seem to be prone to problems i have had 3 of the model 4000 series 1 pre-amps all had problems, and i now have a phase linear 2000 series 1 pre-amp that has just developed problems( just snagged a tube ,sound valves vtp101i on ebay) hopeing that does a much better job on the pre end of things, as far as the amps running hot with klipsch speakers its not gonna happen, i unhooked my fans after i got my klipsch, and i dont get any hom or hiss at all out of my amps, but i do get that little pop when i shut the system off but that could have something to do with the pre-amp just chimeing in Joe

[khorn58]

http://hometown.aol.com/PhaseTek/

This is the place for phase linear info

[lovemyhorns]

I used to have a Phase Linear amp, the 120w/ch model and to best describe the sound would be 'cold & clinical', just my opinion. For SS, I liked my McIntosh a whole lot more... Another note is that I had bought this amp used and when I opened it up, one channel of finals had been replaced, so I guess at one time, the amp burned itself up.

I also have a Phase Linear preamp & still use it, the P3800. this one is actually a Jensen with the PL tag. It has been mucho modified, the bipolar opamps have been swapped out with FET opamps, all the P/S caps changed out to low ESR caps, all the signal caps changed to polyprops and almost every resistor changed out to the Dales and the balance control bypassed. It has a pretty good volume pot. It is now a pretty decent FET preamp. This preamp was also the first 'seperate' I ever bought!

[HDM]

Hi all

I'd like to get in on the debate but my PL 200 has a very noisey channel.

Wondering if anyone can point me to a schematic for it. I checked at the above link but there's only the relay board.

Thanks for the enjoyable debate.

Hugh

[DADUDLE]

AGREE WITH YOU ON Phase 400,had/have one since new, and it is a very stable amp, that flame stuff is just that stuff,that was started with 700s driving bose 901s, I have used my 400 with my 76 K-HORNS AND A VERY GOOD SOUND.David Dudley

[fgarib]

Wow, I never realized that there were such varying opinions about these amps. And no, I hadn't heard about the "Flame" Linear bit.

I still don't have a feel for how good or bad they sound, so I guess I will have to audition the components. More on that later.

Other than this forum, whatever I read is filled with praises of the amps robustness, btw.

Thanks for the input, people.

-F

[fgarib]

Wow, I never realized that there were such varying opinions about these amps. And no, I hadn't heard about the "Flame" Linear bit.

I still don't have a feel for how good or bad they sound, so I guess I will have to audition the components. More on that later.

Other than this forum, whatever I read is filled with praises of the amps robustness, btw.

Thanks for the input, people.

-F

[Piranha]

I had a Flame 400 and 4000 that I bought when I was in the USAF overseas. I had it powering my roomates............gulp........ 901's.

Don't waste your time.

[laatsch55]

Time to wade in in the Phase Linear debate.

A few things have happened since the last post in this thread. Something called White Oak Audio. Since WOA ame out with their new Driver board for the 400's, 700 Ser I's and 700B's, they are nothing short of incredible. WOA"s owner and engineer is Joseph King. He has eliminated the dreaded turn on/off thump, flattened out the frequency response to where it is esentially flat to 10 HZ, being down only .08 to .12 dbr at 10HZ, with the reference level established at 1KHZ. On the high end( 80KHZ) it is down 2.00 to 1.95dbr. These figures were procured with my Audio Precision ATS-1DD Dual Domain Audio test System. These were with a 10 watt output, an 8 ohm load, bias at .385MVDC, DC offset at .007MVdc. 10HZ - 80Khz, UNWEIGHTED. THD & N figures are also greatly improved, but that's only part of it. There are no ceramic caps left on the board--silver mica, polypropylene, and polyphenylene sulfide film along with a few Electrolytics are it. I have completed over 30 conversions now, 16- 400's and 14-700's. The owners are usually ecstatic with the results.

Let me clarify---I am not here trying to promote Joe's product. I have been a fan of Joe's since I started installing his LED replacement light boards in the 400's and 700's. We Have since struck up a friendship and now get to assemble and test any new revision of his boards, lights and cap kits. His stuff is top of the line design and materials.

Yes, I'm enthusiastic about Joe and his stuff, but for good reason, and when I stumbled on this thread felt compelled to respond. A PL with the new board is quiet, like a black hole, no turn on/off thump, no latch up to the positive rail voltage to the speaker outs, and now has bass that will double as a set of CPR paddles when run through my K-clones. the driver compliment is Crites 1526c woofs, B & C DCM 50 2" throat drivers mounted to Al's Martelli Tractix wood horns, finished off with a B & C DC10 horn tweet, and to top it off some of Al's Universal crossovers, and as you fellers already know, a very revealing speaker system.

I own 3-Spec 2's, a Bryston 4B, an SAE 2300, a pair of Cary SLM 100 mono blocks, a Sherwood 300 watt mosfet amp, 4-PL 700 Ser I's, 2 PL700 B's and 8 PL 400 Ser I's, along with a Carver TP-2400 driving some Soniphase SL6 bass bins ( IMHO, not a threat to unseat the finest bass bin ever designed)Nothing comes close to a White Oaked Phase linear. Subjective time now, the PL's are a worlds apart now in clarity, soundstage and much more musical. Joe informed me yesterday that if I wanted a Pl to be as dry and sterile as the Pioneers, Brystons, Yammies etc that it could be done, i politely declined.

This is my first post here fellers, and when i get a little more familiar with posting I'll post up a complete test suite on the latest 400 that went through here, a test bed and guinea pig that has survived several iterations as the WO boards have progressed to a REV "C" board. It's also equipped with a custom set of copper heatsinks I fabbed for it one weekend, and like every amp that has been converted, a Don Imlay DC protect PCB has also been added.

Depending on who wound the transformers ( the early years Bob's brother did) and what day of the week it was , These amps now do between 275-305 watts into 8 ohms, with both channels loaded and driven as the THD & N homes in on 1% THD & N for the 400's. The 700's now do between 475-525 watts RMS under the same conditions. The 2,000 watt load bank that sucks up all this wattage is the same one that was used in the phase Linear factory floor for production testing.

[laatsch55]

joessportster, If you stumble accross a 3300 SerII Pre, change out the electro's with new ones, the op amps with Burr-Brown opa 2134's and you will have youself a fine Pre-amp. The closest thing I've had here that compares to the Spec 1's I have that have been restored to Echowars' recommendations, and some fine pre's they turn out to be.

I have been through a lot of 2000 Ser I's and II's, with the Brown Dog adapter with the Burr-Browns loaded on it for the RC4136 dinosaur they are a very capable pre also.The other op-amp , the RC 4739 has no direct replacement or adapter, but I'm working on something and may in the near future be able to retire that Raytheon legacy part....

Thanks, Lee

[laatsch55]

A quick shout out to Dean and Al. HI guys, good to be here!!

[juniper8]

Laatsch55, you have amazing faith in the 700b after mods, I have one in almost mint condition with the fairly rare boxer fan. pm if your friend needs one for one of his customers....it's been teched with a clean bill, from the most reputable source in my area....I even have the manual which explains shut off procedures...

[laatsch55]

I have an amazing faith in them because they get drove very hard here for at least a week before they're allowed to go. Every one that gets converted also gets a DC p[rotect PCB, takes the worry out of driving the horns to CPR levels. If you would like you can PM me with a price.

[derrickdj1]

but like many other SS amps - too harsh on the high end with the KLF-30's...

Don't blame the amp, the balance of the woofer and tweeter is related to the premap, room correction. setup of old equipment prior to the more advance setup systems common today. I use to think of amp power and other factors related to the amp, but I think the quality of the preamp can't be overlooked.

[laatsch55]

Garbage in/garbage out

[skratch]

I agree, I have done the White Oak conversion and it brings this old powerhouse in a league with the best

[laatsch55]

Just so happens today was the official release of the REV D board. This board will now relace THE FULLY COMPLEMENTARY PL 36 used in the Series II 400's and 700's... Joe's release notes---

PL14_20 Revision D Control Board Assembly now available

After some extensive beta testing (thanks Lee) on this new board version, we are pleased to say that it is now generally available. It continues to build on the White Oak Audio commitment to continuous quality improvement in the design and components used on the board assembly. Below are the release notes that go along with this board assembly. Pricing will be slightly higher than the predecessor board due to increases in costs associated with the new components specified in the improvement areas.

Release notes for PL14_PL20 RevD PCB

1. Move silkscreen legend for R23R that was clashing with Q10R silkscreen.
2. Eliminate unused option resistors and diodes to free up space for additional changes. Components removed from RevC are: R70L,R70R, R71L, R71R, R72L, R72R, R78L, R78R, R79L, R79R, D3L, D14L, D14R (note some of these reference designators are reused in different applications on the RevD PCB, R70L, R70R, R71L, R71R)
3. Change lead spacing for C1L, C1R, C7L, C7R, C10L, C10R to more appropriately match the 0.234” spacing on mica CM05/CD15 type capacitors.
4. Enlarge pads on all mica and film caps to improve board durability.
5. Move components farther away from Q6 bias transistor connections to allow installation of the Phoenix Contact connector on the back side without hitting other pads.
6. Change Q3L and Q3R to MPSA92 and make circuit symmetrical with Q4L and Q4R for better behavior during turn on and off as well as bandwidth improvement. Provision for original 2N5087 circuit is retained with a resistor population option on the board. Added new heatsink requirement for Q3 same as the one used on Q4 in previous versions
7. Provide connection from Q3L/R collector through R78L/R to the B- rail to improve the symmetric current drain on the B+/B- rails. This improves power supply load symmetry and ensures that both supplies power on and decay at very similar rates, improving turn on and off control.
8. Increase the value of C8L/R and C9L/R to improve stability of the bias voltage during active operation.
9. Increase the value of C20L/R to better offset the ESR of C6 and provide more consistent and flat response at higher frequencies.
10. Change vertical mounting hole spacing from 4.0625” to 4.00” to match actual PL chassis mounting hole spacing.
11. Add new lower edge I/O pad to allow use of the RevD board to replace the original PL36 board version in the fully complementary versions of the PL400/PL700 Series 2 amplifier (the last PL36 board artwork added these extra pins). Resistor options and wiring options now enable the RevD board to be used in this application.
12. Increased space around C23L and C23R to allow the use of the same capacitor as C3L and C3R in all locations.
13. Added C21L and C21R as lead network across R15L and R15R in the global feedback path.
14. Added C22L and C22R as Miller capacitors across the collector-base junction of Q5 to tailor/optimize the gain bandwidth and slew rate of Q5.
15. Added R78L, 79L, R78R and R79R in series with the collector of Q7L and Q7R respectively to provision for RevD board use in the complementary configuration.
16. Create new library pad stack for R20L and R20R to properly show the action of the trimmer with respect to CW rotation. The symbol showed CCW rotation on prior revisions.
17. Move connection pads 16L, 17L, 16R and 17R out from underneath C11L, C11R, R77L and R77R respectively to allow simultaneous access to both the static and dynamic bootstrap boost features.
18. Move lower edge connection pad silkscreen numbering upward to increase visibility when Phoenix Contact connectors are installed.
19. Overall, improved upon the already high quality of the RevC board in the creation of the RevD artwork by making small moves of components to improve assembly clearances, shorten and widen traces, increase trace clearances and improve signal integrity to maximize audio quality.

Release Notes

Revision F White Oak Audio Design Proprietary Information

[russ69]

AGREE WITH YOU ON Phase 400,had/have one since new, and it is a very stable amp, that flame stuff is just that stuff,that was started with 700s driving bose 901s, I have used my 400 with my 76 K-HORNS AND A VERY GOOD SOUND.David Dudley

Good times, eh?