Audio Horizons TP 2.0 Preamplifier

I also made the switch to SET 2 years ago and came back to my current, more conventional, set up with the AH dac, pre and Belles Ref 350 amp. They drive a pair of Dali Grand full range speakers (90db effecient).

I liked my SET system which consisted of George Wright 2a3 amps, Cain & Cain IM Ben speakers, matching subs, George Wright preamp and a Audio Aero tubed CD player. In the end I missed the scale and impact of a "full range" system. Sure, this system could play very loud and had good dynamics, but in the end it was not as flexible it terms of playing all kinds of music well. Loved the intimacy of SET, but found I could have it with my current system and enjoy improved dymanics and scale on other music.

I only say AH should consider an SS amp as I think (?) the SET lover is a far smaller group and potential market. I have also found one can get most of that SET sound with a carefully matched and thought out dynamic system. I know some SET systems can be dynamic and have a good degree of impact and scale, but I think we can agree they are still a step behind the best "conventional" systems in this regard.

Bill

I switched from solid state amplification to SET combo with a 95db efficient speaker and never looked back. Its very revealing especially with Joseph's preamp. It also makes it possible to match inexpensive digital as the source while preserving musicality.

I forgot to mention that amps and speakers also have to be matched up properly. Another tough decision for Joseph because of the wide variety of speakers in our systems. Yes, I can understand with Grannyring's recommendation of a 200W amp, but what about the die-hard SET camp using these amps on their ultra hi-efficiency horn systems. I have read a few posts where some audiophiles have gone with the new Zu speakers which are very efficient and are selling their mega-power amps for lower wattage SET, etc. Just another example making it difficult for Joseph to make a decision.

Joseph might agree with you guys regarding SS amps. I believe he has a pair of Levinson monoblocks( personally tweaked and modded) in his personal system. Victor has a pair of older VTL monoblocks which Joseph also tweaked and modded for him. Right now I have the VAC Musicblocs( tubes) and the sound matches very well with my TP 2.0n. I haven't tried a SS amp yet with Joseph's preamp. I can imagine that it would be difficult for Joseph in deciding which type of amp to come out with. You have the tube amp camp and the SS amp camp, and then there's the Hybrid amp camp, the Class D only camp,etc. The list goes on and on. When it comes to amps, there are too many audiophiles with varied tastes. I don't have a clue of an idea to recommend Joseph when it comes to amps. In the meantime, I'm happy with my current system so I won't be considering any more amps for a while.

I would second Bill's request and reasoning. Joseph's genius for "absolute sound" plus ss reliability, ease, and power would be highly desirable.

Correction.

Point #1 - Meant to say mate with a good TUBED preamp!

Bill

I would love AH to come out with an amp. Here is my two cents worth on the type of amp you should develop. It should be an SS amp and it should also be powerful. I would say 200 watts/channel as a minimum. Here are my reasons.

- I find a good preamp mated with good SS amp gives you all the tube "sound & benefits" needed. Having a nice tubed DAC or CD player makes an SS amp even more attractive.

- I am a long time tube nut, but of late have heard SS amps that sound every bit a good as the best tube amps. The current Belles 350 Reference is one example. SS has come a long way! No need to deal with big output tubes that are hot and need replacing etc....

- Powerful SS amps deliver the scale and impact needed to create a live performance setting in a living room.

- Mate this with an AH pre and tubed DAC and you have MUSIC!!!

Joseph and Victor, get a Belles 350 Reference as a benchmark and go for it.

Bill

I have a Harman/Kardon Citation Eighteen tuner that Joseph modded about a year or so ago for me. It's the only solid state component in my system. I can't imagine it sounding better. I wonder what this new tube buffer would do to the sound?

Sherod - thanks for exploring the different caps for us and for reporting the results. I was very interested in them.
Victor and Joseph Congradulations of your new buffer. Its a great option for to explore the enhancement of tubes without changing major pieces of what might have been put together painstakingly to achieve synergy.

Joseph and I like to keep this Discussion Forum informed of news about Audio Horizons that will soon be breaking. With that in mind, I would like to announce a new Audio Horizons product—the TB 5.0 tube buffer stage. We will be running our first ads the end of August.

The TB 5.0 is a tube buffer stage meant to supplement the solid state output of a preamplifier, tuner, CDP or DAC in order to impart to it some of the harmonic richness and the slower, more musical decay time characteristic of tube designs.

About six weeks ago, I heard the first prototype, and yesterday I heard the first production unit. As usual, the production unit is always far superior to the prototype, which itself was impressive.

We listened to the tube buffer stage, using a TB 5.0n, between a solid state preamp and amp, between a solid state tuner and both a solid state preamp and the TP 2.1, between a solid state upgraded CDP and a solid state preamp and the TP 2.1, and we compared the solid state Audio Horizons DAC 2a with it and without it and compared this to Joseph’s tube DAC, the TD 3.0. In every configuration, there was a decided and marked improvement over what preceded it.

The sound seemed to open out; the harmonic texture of the music was much more pronounced; the midrange was sweeter, smoother and more rich; the dryness which almost always characterizes solid state equipment disappeared; and all this was accomplished with no sense of loss, in part because as usual, the TB 5.0 is so quiet---117 dBv in the 5.0 version, -120 dBv in the 5.0n version. Distortion is quite low, channel separation and dynamic range excellent. To our ears, there were no losses and only a sense of significant improvement.

As you might expect the TB 5.0 is as sensitive to tube complement as Joseph’s other design. With two Siemens gold pin E88CC’s it really came alive.

The genesis of the product stemmed from an A-B between my upgraded Sansui TU-X1 tuner and an upgraded Marantz 10B, in which the X1 excelled in so many areas, but not in warmth, sweetness and harmonic texture. Joseph suggested adding a tube buffer stage to it. The rest followed inevitably.

The TB 5.0 shares the same slim line 17” chassis used in the TP 8.0. Incorporated in certain solid state tuners with adequate room like the Sansui TU- 717 or the Kenwood KT 8300, it costs $475; in its stand alone version it costs $595. The 5.0n costs $725 and includes an on/off switch. For balanced inputs and outputs, add $200.

This 5.0 represents the last of our product introductions for the this year. In the back of our mind we are exploring an amp, but amps occur in so many different configurations, and there are so many considerations to take into account, that we will have to proceed slowly.

We will be running two different ads for the 5.0, one in the FM Tuner section, one in the solid state preamp section and one in the tweak section. Those interested, can keep an eye out for them.

Again, thanks for your support.

Victor

Victor,
I also have no anxieties about what you wrote. I have very good center staging with my preamp, but careful room placement of my speakers and proper room acoustics has played the larger role in that department. I have to admit that Joseph did a great job initially when voicing his preamp with the Hovland caps. Joseph might have since found even better caps, but the 4.7 uf Hovlands have a " breath of life" to them that are enthralling. In my experimentation with several types of caps, I recently tried a 4 uf Hovland and the 4.7uf value which Joseph chose sounds much more evenly balanced. Joseph does indeed have very good hearing. My hat's off to him in the development of this preamp.

Victor .y previous set up contained.no preamp.Once I added your preamp the center image shifted.

Victor - No worries! My anxiety did not rise with your post, rather I was trying to suggest that you might be overly worried given percieved balance can be influenced by as Bill mentioned by earwax et al. My AH imaging is dead-on and beautifully dimensional.

Joseph uses a very high quality pot on both the motorized and the manual. The manual is superior to the motorized in terms of channel balance being virtually dead on. We do not feel the preamp is out of balance either at the outputs or at the pot, and I explained why using the specs. It is possible it appears that way to the customer, but that could be because his old preamp was out of balance, because his room is unbalanced, etc.

In trying to reassure people that there is no problem with the preamp, I see I have misled people there is.

In trying to be reassuring, I see I have only succeeded in raising anxieties.

There is no problem with the preamp's balance. We consider this customer's problem, if there is a problem and not simply a difference from his old balance, an anomaly.

Victor

I have the remote version with all of the upgrades and here is what I have found. So many variables impact channel balance that moving my head an inch or two to the right or left is all that is needed to get to that SWEET SPOT of perfect channel balance.

My furniture placement, the recording, room treatments, room shape, other gear and the ear wax level in a particular ear! all impact channel balance. No issue at all with my AH preamp's ability to throw a perfect center image. In fact, this pre is the champ at throwing a wall of sound with a wonderful center image. I find using the XLR's outs also improves the size and focus of the stage.

My only issue is wondering if I should spend the $300 on the new upgrades? How much better is it etc..............

Bill

Victor,
Gammajo took the words right out of my mouth.

Victor, I am a bit confused. Does this issue only apply to motorized volume controls, meaning the remote controlled units? Also it would seem that dead center image is pretty sensitive. I can move my head a few inches left or right and slightly change the apparent centrality of the sound in my system.

I brought Ozzy's perception that there "does seem to be a shift in center stage to the right of center" to Joseph's attention, since we are always attentive to ways to improve the preamp.

Here is Joseph's response, edited just a little: "The gain deviation between channels is 0.2 dB; the tracking error from the volume pot is -1 dB or better when the volume pot is set at -60dB position. This could be an issue for the n version since it has higher gain than nB if the system has highly sensitive loudspeakers. It will be hard to find tighter tolerance available from the supplier of the motorized pot; it will be much easier to get regular pot in tighter tolerance."

I take this to mean that while the the output deviation is small, at some points on the pot at certain gains, with certain highly sensitive speakers, a 1 dB deviation between channels could occur. Sometimes other factors unrelated to the preamp can also contribute a small amount to the perceived deviation.

I take it, without his needing to comment, that Joseph will look for a tighter tolerance pot.

Thank you for bringing this to our attention.

Victor

You're welcome, Ozzy. Once you get back home for some serious listening evaluations, I look forward to your impressions.

Sherod, Thanks for the reply and suggestion.

Ozzy, I would allow at least 60 hours of continous play before you do some serious listening. Maybe you can put a tuner on it while you are gone to slowly break it in. The Hovland caps, as well as the Blackgates take a few days to settle in so the off-center soundstage is more than likely a break-in issue. As you have heard, the Blackgates are notorious for long break-in periods. I'd give it a couple of weeks before you do some serious listening.

I just receieved the 2.1RPNB for trial , plus interconnects and power cord with the Seimans tubes.
The unit was well packaged and looks well built. Unfortunatly, I will be out of town most of next week.

First impression, there does seem to be a shift in center stage to the right of center . I hope this just some strange breakin in behavior.

I would be interested in hearing someone else's impressions of their upgrade from 2.0n to 2.1n.

I see, at long last, that an audio product reviewer has caught sight of an Audio Horizons product - the TD 3.0 tube DAC. A review can be read here:

http://www.dagogo.com/AudioHorizonsTD3.0nDAC.html

The reviewer concludes that the TD 3.0 is a great bargain, without equal in its price range, and for which no apologies are needed even when compared to DACs costing tens of thousands of $.

I've enjoyed my TD 3.0 since it was introduced. Recently, Joseph installed the new capacitors (mentioned in the review and now used in the preamp) into my tube DAC.

I hope others find reason to try the TD 3.0 which, in its own way, is as good as the TP 2.0.

Yes, Joseph changed my preamp.

I was surprised at the improvement - I didn't think the preamp could be improved quite so easily. What I have heard so far are more relaxed and natural high frequencies, and a midbass (~80-200 hz) improvement. Also, it seems to me that various instruments and voices are articulated and positioned more clearly. I perceive the improvements as a more realistic presentation of the musical performance rather than as, say, a lower noise floor that reveals more detail.

Joseph did shield the new output caps, while changing some wires, adding a couple of other caps, and removing the line filter.

I'm glad that Joseph made the change. I have been a beta tester for the Audio Horizons solid state DAC, the tube DAC, and for the TP 2.0 (but not for TP 2.1 or the phono preamp). So, I have had the advantage of seeing Audio Horizons products evolve through the interaction of listening tests and circuit refinements. This upgrade (it is an improvement) shows the value of Joseph's design approach (described on the Audio Horizons website) very well.

Thanks for the imfo Victor.

Count me in for an upgrade, even though it sounds great in original form.

I'm sure the other "members of the family" will be interested as well.

Thanks, Victor...

It sounds like an attractive upgrade path. I had been considering sending my TP 2.0n in soon for an upgrade while on vacation.

I, for one, appreciate the goals that you have laid out, and it represents just one more reason why I love this preamp.

Rob

Recently, Joseph took a TP 2.1nB to Cedar, who in the past has acted as a beta tester for us, to compare to his TP 2.0nB. In addition to a number of small changes made to the 2.1, at the last minute in the 2.1n we decided to replace the Hovland caps used to a larger, more expensive proprietary brand. This decision occurred after I had written my post announcing the impending introduction of the TP 2.1. The new capacitors are so sensitive to interference that each capacitor must be individually wrapped and shielded with thick copper foil.

Cedar was so impressed by the sonic improvement of the TP 2.1nB that he asked Joseph to upgrade his TP 2.0nB and his TD 3.0n.

When Audio Horizons was founded, we had a couple of clear marketing goals: 1) to provide a clear upgrade path for owners so that when they could afford enhancements, they could upgrade the performance of their Audio Horizons components (and thus be certain they were improving the performance of their system) instead of replacing them, and 2) to shun a marketing philosophy based on change and obsolescence.

As part of this second goal, we have decided to put together an upgrade option which would permit TP 2.0n and TP 2.0nB owners to upgrade their 2.0n and 2.0nB’s to 2.1n and 2.1nB. The upgrade will not yield all the benefits of the newer model because some of the gains from improved layout can not be translated, but most of the gains will be incorporated--all those that can be included will be. There are six areas that will be addressed:

1. We will add four capacitors to reduce input switching noise.

2. We will remove the old multipath wiring harness from the RCA jacks to the volume pot and to the main preamplifier PC board and replace it with a new upgraded wire harness, which now comes wrapped in an extra isolating layer of Teflon for better noise suppression.

3. As a result of this harness improvement and isolation and by virtue of shielding the new proprietary caps, we find that the line filter is no longer necessary to filter out high frequency noise; in fact it actually introduces extraneous noise. We will remove the line filter and bypass it. This line filter was never a part of the “n” upgrade: it was always part of the original design and exists in the TP 2.0 as well. It will be returned to you.

4. We will remove the Hovland caps, which also will be returned to you, and replace them with the larger, more expensive shielded capacitors we now use in the TP 2.1n version. Our cost for these capacitors before shielding is just under $80. We think they are worth the extra cost and believe you will agree after listening to them.

5. We will diagnose and address any problems some of you have reported with ground loop issues or tube microphonics.

6. Finally Joseph will inspect the preamplifier to be certain it is operating properly.

Because of size and layout changes, it will be impossible to upgrade the chassis and faceplate.

The cost of this upgrade will be $300. Please understand, these upgrades are not a big profit center for Joseph. We are offering them so that those who want the latest Audio Horizons refinements can order them. The caps are not always easy to get so we will need you to schedule your 2.0n to 2.1n conversion closely.

I have asked Cedar to post his impressions of the sonic benefits of the upgrade. His impressions mirror our own but we thought you would like to hear them from a disinterested owner who has now lived with the upgrade for some time.

Victor

Lak - Glad you enjoyed the read. Let us know when you reviece your unit and what you think. By the time you finish you audition and post comments it will likely be a three and half hour read.
After hearing my AH 2.0 a friend of mine here in town is auditioning the AH phono pre, so I will get to hear the phono unit this week. He likes it already and is currently dialing it in. Time to go upstairs and hear some music.
Peace

Sherod,
Actually I need to update my “Lak's two channel system” page. Over the years I’ve made a number of changes to it however I never updated my “Lak's two channel system” page.
I’m using a Plinius 8100 integrated amp and no longer have a separate preamp in that system. I still own my Cary 2A3 monoblocks but I’m in need of an active preamp to go along with my Audio Research PH-7 phono preamp,(for the occasions when I want to use the 2A3 monoblocks) and my soon to arrive Teres 360 TT and Tri-Planar arm, which will replace the older lesser quality analog gear I was using.

Lak, are you putting together another system? If it's to compare to or replace your ARC Ref 3, then that would be an interesting comparison.

I wonder if the TP2.1 would improve the music quality of Tesla? Seem a bit bass shy!

And why not complete your reading by enjoying the music by "Tesla" found on "My space".

The link :http://vids.myspace.com/index.cfm?fuseaction=vids.individual&videoid=11324008 is shown unless AG removes it.

Gentlemen,
This has made for an extremely interesting three hours of reading today (which just happens to be a very hot, humid, rainy day). Since I’m in the market for a preamp for an analog system I’m putting together, I’m going to have to give this Audio Horizons preamp a listen to.
Thanks for your posts.

I don't know if anyone has noticed this, but in the new TP 2.1nB, Joseph has removed the AC filter. I'm curious about this as the filter was an original add-on upgrade in the 2.0 versions.

http://161.58.252.3/i/s/f/1186200477.jpg

If anyone is still experimenting with tube rolling in their TP 2.0 preamps, in my system I've yet to find a better tube for locations one and three than an early 60's Siemens Cca, but I recently bought a NOS pair of 60's Siemens E88CC with the A-frame halos and put them in locations two and four and the combination is really musical. The A-frames seem to have a larger soundstage with a little more airiness. This combo sounds better to me than all Cca's in the four positions. Here are some similar A-frames to the ones I found, except mine are date coded A3, while these are A6:

http://cgi.ebay.com/NOS-Siemens-JAN-6922-Matched-Pair-Gold-Pin-E88CC-7308_W0QQitemZ320143186035QQihZ011QQcategoryZ67816QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
I'm still experimenting with output caps but for the time being I am back with the original upgraded Hovlands. I'm going to try two more caps and then make my final decision. Happy listening everyone. I hope you're enjoying your systems.

I would like to thank everyone who took a moment to express their opinion about the pending review. We have taken your advice to heart and will, as most of you suggest, send the line stage TP 2.1RnB--we include the remote because the reviewer asked for the remote. Since he is willing to also audition the phono stage, we will send him the TP 8.0cMCpn, which is our top line phono preamp, playable either amp direct or through the 2.1.

For our cable fans, you might be pleased to know the reviewer wants us to send our power cords and cables along, which we shall do.

I hope with all of you that this is a break through opportunity for a very sweet guy and an extraordinarily talented designer--Joseph Chow.

My thanks to all of you again.

On a different note, a supplier of extremely fine Siemens early 60's NOS CCa tubes--both Gamajo and I are very pleased with them--has more of them to sell. they are $350 a pair, and $650 a quad. These tubes will last 10,000 hours. Please contact me if you are interested.

Victor

Agree with all the above :

Review the top preamp *without* the phono stage (as a line only, how it originated)

Also, I'd like to see it pitted against some big-name, expensive preamps we're familiar with reading about in these threads.

Congratulations to Joseph "Commander" Chow (I like that La45 !) and Victor Comerchero.

You've received some good advice from other Audio Horizons customers. I'll add my "amen" to their comments.
I recommend that you send the TP 2.1 equivalent of either the TP 2.0nb or the TP 2.0nB, which are the versions of that preamp that perform at the highest level.
The upgrade path is an important story.
I would take the same approach with the phono preamp. Send the best performing version of the stand alone unit. It doesn't have to include all of the possible variatiations and features (i.e., it doesn't have to be the most expensive version) but it should perform at the highest level

-

Dear Joseph and Victor,

As with others here, I'd suggest going with the top-of-the-line version. I would also suggest that you make it extremely clear to the reviewer (and I would hope they'd include the information in the review) that there is a very accessible entry-level price point in addition to a very well-defined upgrade path for the unit being reviewed.

I consider this to be one of the strengths of the TP line; start with what you can afford and upgrade when you can, knowing that AH will take good care of your preamp.

I'm not so sure about including the stock EH tubes, though. I wasn't terribly impressed, to be truthful. After I installed the PQ White Labels, I was absolutely hooked. Perhaps you could provide the Siemens tubes already installed and a set of E-H tubes in case they want to note the differences.

As for the 8.0... I believe that you're getting into a tricky area, here. Not everyone is into vinyl... MM, or MC?... The 8.0 does increase the entry price point, making it potentially out of reach for some people... and other such considerations. Overall, I suppose I'd go for including the 8.0 as an integrated unit, but I'd make very sure that the reviewer realizes and notes that it is an OPTION.

I realize that one cannot tell a reviewer what to write, but if you provide enough information and make it clear that the TP 2.0n is a fantastic preamp at an affordable price, with a well-defined upgrade path to audio Nirvana, you should probably fare very well.

It would be my hope, too, that someone posts the review here when it's available!

Best,
Rob

I vote for the integrated for the review. After all its Joseph's signature work that is the subject matter at hand. At this level of importance, this review can potentially put "General" chow (affectionatly speaking) on the map.

His preamp deserves full attention by all audiophiles in my opinion, stock or non-stock. Never had a preamp that had such long term staying power of holding my interest in listening. Nuff said.

I would be inclined to go with your best and with the phono unit separate with clear indications of lowest price unit and ease of upgrade.
But it is a very tough question becuase if the lowest unit recieves high praises at that attractive price point, you would generate much interest(sales)with many deciding "what the heck" and upgrading right away anyway. I would provide the reviewer with a set of stock tubes as well as a set of great cca's, checking specific unit and its tubes for very carefully for microphonics before sending.

I 100% agree with Sherod and you should submit Joseph's best version of the preamp. As I have learned in sales we should always lead with the best product first. Folks need to know what Joseph is capable of - his best work.

I would submit the phono unit separate and also submit the best here. The reviewer can simply state you offer the option of adding this same phono stage right into the TP2.1.

Ok, the last question in my mind is the tubes to use. Here I think you should go with non - NOS's. NOS's are more of an expensive tweek that not all TP2.1 owners will want to deal with. Go with the standard tubes and with Joseph's best electronics and parts!

Bill

I have been using the PEs (5 of them) in my home for the past 2 months. I have 3 on my AV circuit and a couple more on other circuits in my home. What Sherod reports is right on the mark. I now have a PE-4 on order as well as one of Alan's power cords. Each of my friends who have tried this tweak have reported similar results.

By the way, fellow TP 2.0 owners. I just put one of these tweak PE units in my system and it has been the best tweak I have ever tried. I look at it now as not so much a tweak but more as a component. The best $75.00 I've ever spent for my system enjoyment.

http://cls.audiogon.com/cgi-bin/cls.pl?powrcond&1188923292

I think that you should submit Joseph's best for review. For those who can't afford it, they can get the "lesser" model and upgrade later. I also feel that both the linestage and phono should be submitted, either as separate or integrated. The idea is to get an idea for the reader of the review to make up his mind based on the sonic merits of each. As to the magnetic or moving coil option, that would depend on the reviewers preference. He might only have a magnetic cartridge( hopefully not) to use for evaluating the phono stage. It would be nice to read a review of both options. Anyway, my two cents, but I might change my mind later. Congratulations on the review Joseph and Victor. I have high hopes for an honest and thorough review from both a subjective as well as an objective approach.

We have had a request by a web audio magazine to review the TP 2.1 with or without the TP 8.0 incorporated into it.

He has left the decision up to us as to which version we submit. We would like your input on this choice. The reviewer wants the remote option, so that is a given.

Should we, because of its more accessible price, review the TP 2.1Rn ($2695) or should we put our best foot forward and go with our top line TP 2.1RnB ($3490)?

Should we ask him to review the TP 8.0 in a stand alone version or in the integrated version? Again, should we opt for the entry level “n” Moving Coil version or the top of the line premium Moving Coil version?

There are arguments for each, so we would welcome your thoughts on this matter.

Thank you. We appreciate your taking the time to express your views.

Victor

Both of my Audio Horizons components (preamp and DAC) have black face plate and redheart knobs. I must say I like happy coincidence of the redheart name, which is so appropriate to components that consistently provide heartfelt musical performances.

My "dark" knobs are Redheart also. I just now realized this.

And just to be different,silver with the redheart knobs.