The DartZeel 108 and several other amplifiers go on playing at reduced and somewhat distorted level for some minutes after you switch them off because they have large capacitance in the power supply, a modest bias current, a simple circuit and no relay's in series with the input or the output. Most amplifier's disconnect the speakers or mute the input immediately after you switch it off.

I am not as patient as Mike - after a minute I have no problem changing any cables and I never went in trouble - the Darts are really reliable. There is also one aspect you should be very careful when using amplifiers with simple output paths - avoid short circuits in the output!

BTW, I have no experience with the 458 in my system - my findings report to the 108. And yes, in my humble experience and opinion 99% of amplifier faults are due to audiophile cable swapping!

microstrip November 19, 2012 22:15

The purpose of the T adapter with the 50 ohm terminator is to put a resistor of 50 ohm in parallel with the input of the amplifier. This way the Dartzeel preamplifier and cable will see the correct load at both extremes.

microstrip April 30, 2012 00:39

Did you use a BNC T adapter with a 50 ohm plug terminator with the BNC-RCA adapter? I found that it sounded great when I tried Krells with the Dart preamplfier.

microstrip April 26, 2012 20:11

Audiophiles usually enjoy good meals - if you like cuisine basque do not forget the Auberge Etchegorry , at 41 rue Croulebarbe. And for lunch there are a few non inexpensive nice restaurants near Assemblée Nationale - french politicians like to eat well for little money!

microstrip September 30, 2011 00:42

Henry,
Nice to know you are in Paris - I love the place and have been there several times.
Did you get your amplifier fitted with the last upgrades?

microstrip September 25, 2011 19:03

Above 1000 watts with 93 dB speakers? Were you emulating the Space Shuttle launch? :-)

I have listened to the Dartzeel monos at similar level using the Magico M5, that are only 89dB, in an huge room and it was really loud - too much for me!

microstrip September 23, 2011 20:40

AS people say - if it is too good to be true, probably it is not true...

Anyway, when I sell something at audiogon, if I feel the prospective buyer seems to have doubts I immediately advise him not to proceed and stop the deal. Selling and buying in the net is a confidence deal - if the buyer does not know how to check seller suitability, nothing you will tell him can be trusted at 100%. Also remember that a bad sale can get you many more problems than a bad buy. Non experienced buyers often expect that 20 years old used goods at one tenth the original price look as new ...

microstrip September 15, 2011 20:45

Mike,

Are you connecting the wires from the tape head directly to a modified Dartzeel phono board?

microstrip July 30, 2011 23:19

And every 6 months when I see your answer I say someday I must buy one (may be two...) of these chairs! But having to import it in Europe is an expensive process.

Do you know witch particular current model corresponds to your chair with the narrow top?

microstrip July 24, 2011 22:20

Mike,

Are you using your OPUS MM2 with the low power SE?
BTW did you manage to compare the OPUS MM2 with the Nordost Odin?

microstrip May 07, 2011 21:20

Mike,

Did you carry more tests with the Equi=tech?

microstrip January 14, 2011 19:14

Mike,
I have no experience with either the Equi=Tech or the Tripoint, but for me there is an important difference between the units - in the Equi=Tech site I have photos, technical specifications and details about their units, but unhappily there are no technical details in the Tripoint site - only references to patented techniques without patent numbers.
I admit that the Tripoint can be a marvelous device but I think it would not be a coherent part of your system.

microstrip November 22, 2010 23:47

Mike,
When you use the Dartzeel system (amp, preamp and cable) you are using a 50 ohm cable system similar to what is used typically for high speed instrumentation. This system avoids reflections in the cable because source, cable, connectors(!) and destination all have the same impedance - 50 ohms. It is why the cables can be so long without losses.

I assume that the Evolution cable is also 50 ohms - otherwise the system would be mismatched.

The Lamm's are not balanced - the XLR just duplicates the high impedance RCA for convenience. The only way to recreate a similar connecting path is putting a 50 ohm resistor in parallel with input at the Lamm size - you can do it with the T BNC and a 50 ohm terminator. I did with success when using the NHB-18NS with amplifiers other than the Dartzeel - as you said the balanced output was not so good as the single ended ones.

microstrip October 09, 2010 18:40

Mike,

If you want to use the long Darzeel 50 ohm cable you should use two T BNC adapters and two BNC 50 ohm terminators, not only the BNC-RCA. These cables must be terminated with 50 ohm. Otherwise, you will be compromising the performance of the ML2.1 Lamm's.

microstrip October 09, 2010 15:44

Mike,
I went through a similar situation sometime ago, but was luckier than you. I have always admired the Audio Physics Kronos, a large speaker with an active bass system having eight amplifiers and eight woofers and two lateral midrange units. When a good friend decided to change his pair they went to my home. As soon as they arrived I did the usual procedure – I measured them. One of them had a small suck out in the middle frequencies - I only noticed it because I could compare the individual responses. When I opened the speaker, I immediately noticed that one of the mediums was connected out-of-phase, switching the terminals solved the problem. They had been operating this way for more than five years!

Even with the proper phasing , the Kronos could not surpass the current speakers, so I still have a speaker that can not have the units out of phase as it has a single unit – the Soundlab A1 PX.

My advice – from time to time we should test our systems with an analyzer – I use a Behringer microphone with an EMU tracker USB box and a PC. If something goes faulty, most often only one channel will be affected – testing the channels separately is a good strategy. Our ears have a large accommodation factor – we quickly get used to the best, but also easily accept progressive faults.

It is little consolation, but think that you were able to hear the problem during all this time– this only shows that you are a good listener!

microstrip September 26, 2010 23:51

Mike,
Congratulations for the equitech. I have everything prepared for a similar transformer in my system, but as equitech has no representative in Europe, I am looking for alternatives. Did you install a separate ground feed for your equitech?

microstrip August 19, 2010 23:23

Mike, may be I misunderstood you - do you think that the new Evolution Acoustics BNC cables between pre and power was more effective in your system than changing to the monoblocks?

microstrip April 09, 2010 00:17

>the Rockport simply digs deeper into the grooves and 'communicates' musical truth. in a way that trancends discussion of parts of the music. the musical reproduction becomes more real due to the musical nuance and delicacy revealed.
>end of citation

I was discussing the sound of the Forsell turntable and tonearm in similar terms with a friend some time ago. My experience is with small compared to yours - I owned many Linn's, Oracle's, Pink Triangle, Sota, an SME30 and a Clearaudio Reference, but for me my current Forsell Air Force One surpasses all others in communicating the music because of the way it "fuses" the micro dynamics in the global. The Forsell is like a diva - it needs special tables and the fly-wheeled motor electronics is a disaster, belt material and tension are critical but once you manage to solve all its small engineering problems it is in another level. Your Rockport should be next one!

microstrip April 04, 2010 16:44

Mike,
Could you refer what were your music choices for this Marathon music session?
Regards

microstrip February 04, 2010 01:17

Hi Mike,
Have you considered having the second phono card of your Dartzeel modified to accept the direct output of the heads of your tape recorders (Bottlehead style)?
Then you could compare the A90 with your Tapeproject recordings ...

microstrip November 03, 2009 23:14

Nice to see you have added an Allnic H3000 to your system. How does it compare with the Dartzeel phono?

microstrip July 23, 2009 00:34

Mike, how did you get these incredible 15 1/4 tapes that you are referring? Have you considered using a Tube Repro by Bottlehead head amplifier for your A820?
I am just waiting that my Tape project reels are released from the customs.

microstrip April 16, 2009 01:14

Both cables of my Valhalla XLR pair, bought from the authorized distributor, have the same number engraved in the left and right cables. You should contact Nordost with the serial numbers before buying.

microstrip April 01, 2009 01:30

I have tried Shunyata Antares, Nordost Valhalla and XLO Signature between the DarTZeel pre and amplifier and the 50 ohms BNC was always better in my system, independently of other cables - I always used complete sets of cables of the same brand and type.
When using non BNC cables the RCA options were better than the XLR.

microstrip March 21, 2009 22:01

Jtinn,
Thanks for your answer. But curiosity got me - is it a diaural or Sonus Faber Extrema type crossover?
Next time I will be near Geneve I will have to accept Herve offer to listen to his EA MM3's!

microstrip February 23, 2009 23:39

Mikelavigne,
Thanks for such a detailed report on your findings on the GUB.
I could read that the EA have the ability to control the crossover, the tweeter, the fullness of the bass and the bass extension. Do you know what is the range of these controls? The new Grande Utopia EM also have these possibilities, and I have seen that some of them can be easily fitted to the old GUB. Do you know what type of capacitors is used in the EA's ?

microstrip February 17, 2009 23:58

Mikelavigne,
Did you have the opportunity of listening to the new DCS's, either the Puccini or the Scarlatti with DarTZeel?
BTW, how would you compare the tonal balance of the Evolution Acoustics with JM Lab Grand Utopias Be? I can assure you that the GUB sound great with the Dart's!

microstrip February 17, 2009 00:25

I have tried several preamplifiers with the NHB108B - when I got it the NH18NS was still under development.
Even with ballanced preamplifiers, such as the Audio Research Ref3, I preferred the unbalanced connection for a fuller and more musical sound, although using high efficiency speakers the balanced connection was preferred to get rid of some common mode noise.
Both the conrad johnson ACT2 and ACT2 series 2 also sounded good, but only when I got the NHB108B with the Dartzeel 50 ohm cable I got the magic of the Darzeel system.
Since then I also tried the Dartzeel with VTL and Krell amplifiers. I got the best sound using the Dartzeel BNC coaxial (unbalanced )cable terminated with a T BNC adatper having a 50 ohm terminator and a female BNC - RCA converter. This mode is particularly well suited for driving a fill-in subwoofer - the NH18NS has two more pairs of independent 50 ohm BNC outputs and one of them can be used to drive the subwoofer.

microstrip October 16, 2008 14:00

Just before I wrote this message I have been listening to Bartok Concerto for Piano and Orchestra No 2 on the Dartzeel combo. To answer your question I just cut and pasted Mtkhl567 opinion - "extremely fast, dynamic, controlled and coherent from top to bottom".
Orchestral dynamics are excellent.
The Dartzeel system is not mellow - however it does not have the sense of power that sometimes is associated with the idea of a "fast" amplifier such as a Krell FPB750 Mcx or even a cj Premier 350. Also, if you use the Dartzeel with inappropriate speaker cables or speakers it will sound lifeless.
Unhappily everything that I read about burn-in is true : it needs a long time burn-in, more than 500 hours.
BTW, speakers were the Krell LAT1000, speaker and interconnect cables were Nordost Vallalha and a CD7 cd player by Audio Research was used as source.

microstrip October 13, 2008 19:47

Although, as you say, everything has been so crazy for the last few weeks, the room is still the thing! Can I ask why you are choosing the RPG skylines and not the Diffractal or QRD 734?

microstrip June 04, 2008 23:15