REVIEW: Decware Select Zen CSP2 Tube Headphone Amp - Page 8

Thanks for a quick response.

Phoenix, while great at what it does, is not my type of amp. I found it to be little too edge and harsh(?) sometimes.

I am eying either this (after your great review) or NDA Sonnett. The price wise, Sonnett is a lot more expensive, but if I have to, I will add more fun and get Sonnett.

WA22 is also very tempting, but it's little over my budget after spending so much on can/source/amp (which I just lost nearly $400 for 1+ month use)

Have you had a chance to audition the Sonnett? If yes, how does it compare to this? Which amp would better suit me? I like more rounded and little warm sound (which is why I am leaning toward the tube amp).

Thanks.

Skylab,

I see that you have used the SP 274B in the CSP2 for a few months now.
How has the 274B been working out?

Unfortunately I fried an EML 274B Mesh in mine, and according to George at tubesusa, that tube is incompatible with the CSP2 design (George and Steve discussed the situation, and determined that a choke is required for the EML - the CSP2 does not have one).

So, I'm trying to determine if the CSP2/274B compatibility issue is unique the the EML, or if all 274B tubes will suffer a reduced lifespan.

Yeah, based on the CSP2 manual stating 274B compatibility, the great sonic performance of the SP 274B in my WA6, and the positive comments in this forum on the EML 274B in the WA6, I plopped one in the CSP2.

The end result was:

George,
The tube died today.
It was installed in a Decware CSP2, and had less than 300 hours on it.

Hi John,
Thanks for your detailed image here. I can see the cap values on most of the caps, but I'm afraid that the 220uF caps are the caps coming off of the rectifier. . . From what I see, this tube has been "cooked" due to larger than recommended capacitor values for the EML rectifiers, or higher than usual line voltage. I have seen a few tubes with this greyish black deposit on the glass(all the result from either issue). You cannot use an EML 274B or A with a first cap value of over 4uF. . . .
George

George & Steve,
I thank both of you for your products and great support.
It looks like we may have an incompatible combination, but I do not have the technical information (or understanding) needed to support the troubleshooting effort.
Steve,
Could you please contact George to help resolve the incompatibility?
Thank you all,
John

Hello John,
I spoke with Steve today, and we had a long conversation about the power supply. There is NO choke in your unit, and along with having to much capacitance towards the rectifier, the tube was doomed to failure from the beginning. Emission Labs shows the optimum power supply circuit to correspond with these tubes under the 274A/B icon on the tubesusa.com website, and you MUST use a choke when using their rectifier tubes. . . Steve says that he can do the mod for you, and I have instructed him, as well as directed him to the information on the tubesusa.com website to facilitate this. . . This has happened before to other's out there with different equipment. It's rare, but it happens. The greyish black appearance suggested to me that this was the issue. . . .
Best Regards,
George

So,
1 - The SP 274B also sounds great in the WA6 [me and other Head-Fi'ers]
2 - Do NOT use the EML 274B in the CSP2 without mods [me (sigh)]
3 - Is this a great obsession/hobby/business, or what? When do you ever get the heads of different companies collaborating together to solve some end users problem? Thanks George and Steve!
4 - The SP 274B sounds great in the CSP2, and seems to be lasting ok, so far [Skylord].
5 - The EML 274B works well in the WA6 [George and other Head-Fi'ers]

Also,
The EML 5U4G may or may not be suitable in the CSP2 [I've asked George, but don't have confirmation, yet]

Side note: I don't know about the rest of the community, but I will benefit from a better understanding of the theory, designs, circuits, components and science behind our obsession. It's too easy to get forget that there are hard realities in our world of perception and subjectivities.

Any comments or corrections from anyone?

Skylab,
Thanks - it's on order.

CSP2 with Beyerdynamic DT880/600

I've had the headphones for a couple of weeks but just got the amp today. The phones have 20-30 hours on them running strait off my ASUS STX sound card (set at 600 Ohm gain) so they have settled in quite nicely (they actually sound better than they should in this set-up).

The Amp now has about 4 hours on it tonight and will need some more time but I really like what I'm hearing! I used the stock tubes to make sure everything was working. Listening to some familar tracks and I noticed much more depth in the music. Instruments seem to have more space between them. On Boz - Loan me a dime (one of my favorite test tracks) I could hear all the instruments break out against the others. However Mr. Allman's guitar seemed a bit harsh.

I rolled in an old GE rectifier and three of my prized CV2493 Mullard gold pins and replayed Boz. Yes I am going to like this amp, more dynamics, superb noise floor, same seperation but instruments were all much smoother.

My daughter came in and listened to some Cold Play. Her eyes opened up in amazement. Now she wants one...

Left it playing all day while I was at work (yes a little scary with tubes). Tonight I am playing the Allman Brothers live at Fillmore East and I gotta say this baby is really starting to open up! Duane's guitar sounds simply awesome!

After several weeks of burning in both my CSP2 and Beyerdynamic headphones I can say this combo is quite sweet. I installed it on my system #2 today. As a preamplifier it does a respectable job but not in the same league as my First Sound. As a HP amplifier connected to the music hall DAC combined with the Beyers it is simply awesome! Great noise floor, great sound stage, SQ is natural and balanced. Respectable lows, calm and accurate highs, mid range is a little aft but full. Now I'm listening to a SACD thorugh the Maverick...:music:

Current tubes are Mullard CV2493 with an old GE rectifier.

Have the Decware back in my office system #3 and just installed an NOS Sylvania 5Z3 rectifier with an adapter. My God! I thought this baby sounded great before but now the Beyers are making a sound so sweet they bring tears to my eyes. Extension, full body, and very, very smooth come to mind. Midrange has come way forward. Background instruments seem to appear with more presence than with the GE.

Listening to Dizzy and Monk, Europe 71 tracks and I'm in awe. This Mullard CV2493 & Sylvania 5Z3 combo is great!

Those damnable 1980's Phillips production 6922's have a high failure rate and short life. Best to look for pre-1976 Sylvania production in either the 6922 or 7308 type.

That was once my MLB. It was very well taken care of and was updated by DECWARE. It is cute as a button. On its last trip to DECWARE, Steve placed an internal OC2 tube to regulate the input I believe.

Skylab, I see you are using the CV2492s now in your CSP2? How do you like them compared to the BBs? I like the BBs but find myself keeping the CV2493s installed most the time. Awesome tubes that leave nothing behind...