Review of Xenos 3HA!

[kaushama]

I got my Xenos 3HA as I was fascinated by the different topology it uses, claimed to be scaled down from power amps!

• It uses Texas Instruments NE5532 Op amp in the input stage where it includes bass and treble control options.
• The power stage eases the burden of driving the can from the signal processing stage and uses quad bipolar complimentary transistors for that! Usage of transistors has been a subject of controversy too.
• Power supply is a switching supply [another controversial feature] and seems to have low pass filters on output to eliminate switching ripple and noise. It has Dual output power modes for Battery and DC!
• It uses four NIMH AA cells and switches 4.8V to Dual 10.5V to get ample juice to run the can even in battery powered mode!
• It has a capability to run two cans simultaneously. Runs 16 ohm to 600 ohm cans!
• It uses good isolation and shielding between input, output and power stages!
• More than anything it is 129$!!!!!!

I received it in a well protected package and it included a tiny little switching type adapter, a regular mini to mini interconnect, mini to RCA cable and four 2500 mAH batteries! A real bargain for 129$!

The amp is well built with tough plastics and has screen printing over the faceplate. It is not the smallest of the amps I have seen and compared to my PA2V2 is large which can be used for desktop listening than mobile listening!!!

I have listened to it with my Koss KSC 35, Sennheiser HD 497, Senn HD 595 and Sony EX71 . I connected the amp to HD 497 before breaking it down, to hear a hum when the volume is turned to max range without a signal from a source! This is when I use the little PSU it comes with! When used with a TREAD supply is ultra quiet and with the battery supply gives same silent output. When I mailed the Alberto of customer service, he promptly replied with the solutions and promised to send a replacement PSU.

Wonderful customer service!!!

I used an iRiver ifp 795, iRiver IMP 450 CDP, Audigy 2ZS and my wonderful Chaintec AV 710 as sources. Interconnect used, a DIY starquad cable made out of Neutrik connectors and Klotz cable.

Vow! When I hooked up the amp, I immediately notice the improvement in audio. The sound is crisp and extended soundstage with crystal clear mids and Bass! The treble is very clear and not harsh and has the finest details in it! Bass is very discrete, fast and punchy! I could hear finest details in music I could not appreciate earlier with my PA2V2! Nice separation of all the instruments and very clear vocals! It drove both low impedance and high impedance cans with ample juice and in fact has too much gain!!

After initial impression I ran the amp from AV710 for 24 hours continuously to find it has changed a quite bit in sound signature! Now the bass is so deep and hits the lowest notes especially with Senns! Bass is clearer and has more punch in fact I had to reduce it with the bass control! Gosh! These controls are really helpful! It has very wide range of control to a limit one can get a distorted and clipped Bass and treble if it is cranked fully. It can kill the bass and treble if it reduced to zero! It served me very well when I listened to my tiny Sony tuner with does not have a decent EQ capability!

I am so impressed with the detail, clarity and extension it gives to various genres I listened! Sound is so neutral and not colored at all! Texas Instruments NE5532 seems to be serving well! The biggest improvement is with my harsh sounding Sony EX71 ! The boomy and muddy Bass seems to be more controlled now and harsh trebles are replaced by nice crisp extended notes with more prominent mids! I wish if amp would have been smaller to carry it around with Sony. The Koss sounds better with the amp too.

As I listen through the days I still could hear an improvement over the clarity and wider soundstage. I could not hear any difference between the DC powered and battery powered modes both in quality and volume!

I ran the amp about 7 hours continuously with a full charge of the batteries supplied. Before batteries started to exhaust the Bright blue LED started to pulsate indicating about 20 min of battery power is left! Nice touch!

I really like this amp which is a bargain for 129$!

I wish it was smaller in size and had more battery life in it!

 

[xand1x]

Thanks for the review! It would be nice to hear how the amp performs out of a higher quality source =P. Nevertheless, if it can sound that good out of the sources you say it does, then yes it is a bargain for the price! If you ever consider an upgrade in the near future I'd recommend you upgrade your pc sources

 

[HiWire]

Great review. Enjoy!

 

[kaushama]

xand1x, What would you recommend as upgrades for my pc sources?

 

[spinali]

Nice review, and it corresponds with my experience of well over a year. Those treble and bass controls are enormously useful for tweaking the sound on the fly. Although I'm gettng a SM3 soon, I'll be keeping the 3HA.

I wonder if there would be a difference in tone if the ONSEMI op amp replaced the TI?

If you're a portable fan, I hear the 1HA is coming out some time soon - a portable version of the 3HA (without treble and bass controls).

 

[kaushama]

Yeah! I heard that miniature version of 3HA is forthcoming! But it would not be wise to loose those nice bass and treble controls for relatively not so lesser price tag than 3HA! The controls are really helpful and they are the signature of this nice amp. Wish they can shrink the amp with those controls on top of it!

 

[kramer5150]

Nice review!!

I thought your commentary was a little glowing at times... But heck if excitement and surprise are part of your impressions, then no point in toning that down any.

Ive always believed low impedence/ high sensitivity canal phones benefeit tremendously from amplification, as much as anything else. Nice to know at least one person feels the same.

7 ours battery life... thats a bit of a downer IMHO. Me, being used to my PA2V2 and govibe II. But I guess thats the price you pay for stepping up the voltage like that, in order to achieve that level of performance off the batteries. IMHO very few portable amps sound identical running off DC and AC.

Curious... what is the mAh capacity on the AA cells youre using? They make up to 3000 now I think. My PA2V2 runs for over a month (!!) on Lenmar 2450 mAh cells.

thanks!!
Garrett

 

[Skylab]

Nice review. I agree that the 3HA is a nice amp, and a great amp for the money. Couple points:

> Alkaline Batteries got about 20 hours or so. The thing is a hog.

> It provides more gain when powered from the AC adapter than batteries, but the thing has gobs of gain, so if anything I wish it had LESS gain when AC powered.

> It sounds a little thin IMO with the tone controls centered, but since they are always in the circuit anyway, this really is a non-issue, since it's so easy to warm up the sound. The tone controls really are useful.

I really like the 3HA. I confess I don't use it much, because it's too big to go in my briefcase, and it's no match for my Meier HA-2. But I take it when I go on vacation or away for the weekend, and it's too nice an amp to part with, esp. since it's so inexpensive.

I have ordered a Xin SuperMacro3, I will post some comparisons when I get it -- I plan to compare it, the 3HA, Porta Corda, and Total Airhead.

 

[kaushama]

I have used the Vapextech 2400 mAH batteries they have sent with the amp. The time might improve with next charge as the first charge of these batteries usually does not give their full apacity. Yeap! As you thought I was full of surprise of the nice listening experiance I got, for the price I paid and just let it flow!!!

 

[kaushama]

a late addition to the PSU options: The tiny little switching type of PSU supplied with the amp was known to cause a little bit of hum at fulll mark of volume for some people at least! As the amp was ultra quiet with battery supply and LM317T based PSU.

Having a switching PSU for the amp must be giving it little distortion to the audio output which will not satisfy a demanding audiophile! Further it supplies another step-up internal switching type of power stage though there are sufficient filters!

Switching type of PSUs are not well reputed amongst audiophiles!!
Alberto of the ATP systems promised me to send a better regulated PSU which is about 1.5 times larger than the tiny PSU. The purpose of the tiny PSU seems to be portabilty according to the Alberto. They experimented to have a filter circuit between PSU and amp in a bid to salvage the unmatched marriage between the tiny PSU and Larger amp! According to Alberto they got more pure power signal with that on the scope.

Having a smallest but well not implemented PSU with an amp which is not the smallest seems to be a paradox of concepts to me!

The amp seems to be serving the range of listners, who need a nice sounding amp which is relatively cheap and who do not mind the large form factor! So ATP system should have given the option of choosing between a paradoxical concept and a better implemented PSU for their customers. Any way their customer service has been one of the best I have come across recently.

 

[Andrea]

Glad to hear you're happy with the 3HA

I've just added a QED J2P interconnect between CDP and amp to replace the silly one I was temporarily using and things have gotten so much better! Fuller+warmer+cleaner=happy me

I'm loving the transparent sound of the 3HA.

 

[kaushama]

Ok I received another bit larger switching power supply from ATP systems! That PSU is better than the previous one but has significant amount of hum when the volume is at maximum without a source being connected to the amp.
That concludes that the switching type of PSUs hooked up to this truly wonderful amp is not serving it any justice. In the descending order, the amount of hum I experienced with various PSUs follows,
1.Xenos original PSU (Significant Hum +++)
2.New switching PSU (++)
3.Unregulated Bridge and Cap: 2200UF (+)
4.LM 317T Based linear regulated PSU (0)
5.Battery Powered (00)
Please note that the hum I am telling you about is a very faint one and not audible when running the amp at 40% mark! But the point is, it should be giving the amp some distortion in the final signal. It is not the most optimal amplified signal, the amp is capable of, is being delivered with the PSU supplied.

I have built two LM317T type PSUs for desktop and mobile usage. As it is connected to the wall wart at some distance, the AC hum is not delivered to the final dc wave too. The adapters of ATP systems records 12.4V and 12.3V respectively on DMM. The LM 317 circuit, I built with the resistor value (736Ohms) at V-adj, gives me 8.92V! Should I crank the Vadj a bit to increase the voltage or this is sufficient for the optimal performance?