soundstaging, imaging, tube mid's, absolutely no listener fatigue, value for money

needs subwoofer support to obtain a strong presentation across the musical spectrums

I've had 2 years with this little integrated and gone through all the necessary doubts and uncertainties as to if it should remain in my system. This was an initial purchase and since them I have added in a Rega 25 table with Benz Glider cartridge and Target wallmount, an Audio Analogue CD player, a vintage Kenwood 600T tuner, mostly Cardas wire all around and Monster power conditioning. Right now I'm running Mirage OM10 speakers which I got for a song. I've also made another recent purchase I will explain later. A speaker upgrade also seems to be in my future.
While going through all this acquisition, I have obviously spent a considerable amount of time going in and out of audio salons, reading the mags, hooking up with audio buddies, going to live concerts, buying software including new and used vinyl, attending record shows, etc. Basically becoming a died in the wool novice audio geek.
Through all this, my Anthem amp has survived the analysis, doubt, second thinking and comparison.
I've read some of the luke warm review materials and re-read them. Obtained comments and observations from near and far, friends and salespeople and anyone else who cared to talk to me or listen to my system. But what I've done more than anything else is listen
to music throught this piece. And so far, I'm still committed to this integrated. I think that says something to me anyhow.
I've brought theMusical Fidelity integrated home and almost fell for a Celeste W3 which I thought I might run with the pre on the Anthem. I'm sure that would have sounded good, but money talks right. Bottom line, this is a quality piece. I read with interest in this section the advice from Sei-Young Jang and may consider some of the tweaks he recommended. Also, the binding posts really suck and I plan to switch to Cardas soon. Bottom line, if you can find one used under $700, it's a good buy. Better yet if it's under $600. I understand most of them sold in Asia, so there probably aren't tons around. Don't worry about the power. This thing actually cranks about 40 tube watts, and anyone with a little knowledge knows that converts 3 to 4 times to solid state. Even at a way too conservative 2x, you still are running 80 watts per. I'm an analogue guy, so I didn't find the Integrated phono stage could continue to meet my needs. I recently purchased an Anthem Pre 1P stage to better match my table and moving coil cartridge. That was a nice addition. And as you can see, I had enough confidence to buy Anthem again. My plans for the future. If I can't buy it used, I ain't getting it. Have fun!

detail, smothness, transparent

Bass, power level

I write this review for those who own this and love this amp AND who hopes to improve this. Anthem Int1 itself is a good tube amp, even though has many limitation as written in the reviews listed below. To me this was my first tube amp and I loved it from the beginning. As time goes by, I began to realize its limitation and my desire to hear more and better grew as well. Having been an electrical designer for years, I started tweaking the design by replacing the parts and modifying circuit. The result was tremendous and too big, I simply wanted to share with you.

First, changing the coupling capacitors in preamp section makes big change. Originally Cin (0.022uF) is cheap mylar and C1(output cap) is MPP from Solen. Changing them with Music cap(Film and foil PP) or RTX grade makes heaven to earth difference. it will cost about $100 total, but really worth!!!

Second, it may sound absurd to some, add three 100uF 630V MPP capacitors to input bulk cap. Yes, I mean input capacitors for main power supply. It's not cheap, about $150 for three 100 uF 630V MPP from Solen. If you can disassemble the chasis as I did, delete the electrolytic caps (four 330uF 250V, C1-C4). Result? Huge Bass! Pure high! Detail of details. Now your int1 is completely different animal. With these two step modification, one of my friend who loves to play drum was shocked with the improvement in the bass. "Before I cannot hear the kick drum, the real low bass. Now I can hear them and it's tight."

If you can follow little bit more, I suggest step 3 as well. In the center of the main PC board, there are electrolytic capacitors, C5, C5A, C6, C6A, LC6, LC6A, which are 22uF and 33uF 250V caps. repalce them with Solen MPP. 10 uF 630V will replace two 22uF Electrolytic caps which are connected in series. 15uF will replace two 33uF as well. These are power supply capacitor for drive stages. This brings transparency one level higher.

For next steps, you can replace two mylar caps(C19, LC19) with RTX (Film and foil PP). Also C20, 21, LC20, LC21 with RTX.

With these modification, I believe you will not find better sounding tube amp in the price range below $3000-$4000. I rent my (modified) amp to my friend who was looking for good tube amp for a month and together we went to shop to audition, but even 5K$ tube amp didn't sound better but sounded dull compared to mine. Finally he asked me to sell mine, which I did and I bought another one used and did the same mod.

After the mod, Int1 sounds transparent, very much detail, natural, much bass with tight control. With upgraded source, it really reveals.

My system :
Philips CD950 and DVD Pioneer DV-333 as Transport
Perpectual technology P-1a, P-3a ( 24 bit dac)
Anthem int1 modified
B&W N 805
Silversonic Interconnect and Speaker cable.

For all the parts I mentioned, you can get from Part Connection of SFI. (www.sonicfrontiers.com/tpc)
You can buy schematic from SFI as well. Hope this helps.

detail, smothness, transparent

Bass, power level

I write this review for those who own this and love this amp AND who hopes to improve this. Anthem Int1 itself is a good tube amp, even though has many limitation as written in the reviews listed below. To me this was my first tube amp and I loved it from the beginning. As time goes by, I began to realize its limitation and my desire to hear more and better grew as well. Having been an electrical designer for years, I started tweaking the design by replacing the parts and modifying circuit. The result was tremendous and too big, I simply wanted to share with you.

First, changing the coupling capacitors in preamp section makes big change. Originally Cin (0.022uF) is cheap mylar and C1(output cap) is MPP from Solen. Changing them with Music cap(Film and foil PP) or RTX grade makes heaven to earth difference. it will cost about $100 total, but really worth!!!

Second, it may sound absurd to some, add three 100uF 630V MPP capacitors to input bulk cap. Yes, I mean input capacitors for main power supply. It's not cheap, about $150 for three 100 uF 630V MPP from Solen. If you can disassemble the chasis as I did, delete the electrolytic caps (four 330uF 250V, C1-C4). Result? Huge Bass! Pure high! Detail of details. Now your int1 is completely different animal. With these two step modification, one of my friend who loves to play drum was shocked with the improvement in the bass. "Before I cannot hear the kick drum, the real low bass. Now I can hear them and it's tight."

If you can follow little bit more, I suggest step 3 as well. In the center of the main PC board, there are electrolytic capacitors, C5, C5A, C6, C6A, LC6, LC6A, which are 22uF and 33uF 250V caps. repalce them with Solen MPP. 10 uF 630V will replace two 22uF Electrolytic caps which are connected in series. 15uF will replace two 33uF as well. These are power supply capacitor for drive stages. This brings transparency one level higher.

For next steps, you can replace two mylar caps(C19, LC19) with RTX (Film and foil PP). Also C20, 21, LC20, LC21 with RTX.

With these modification, I believe you will not find better sounding tube amp in the price range below $3000-$4000. I rent my (modified) amp to my friend who was looking for good tube amp for a month and together we went to shop to audition, but even 5K$ tube amp didn't sound better but sounded dull compared to mine. Finally he asked me to sell mine, which I did and I bought another one used and did the same mod.

After the mod, Int1 sounds transparent, very much detail, natural, much bass with tight control. With upgraded source, it really reveals.

My system :
Philips CD950 and DVD Pioneer DV-333 as Transport
Perpectual technology P-1a, P-3a ( 24 bit dac)
Anthem int1 modified
B&W N 805
Silversonic Interconnect and Speaker cable.

For all the parts I mentioned, you can get from Part Connection of SFI. (www.sonicfrontiers.com/tpc)
You can buy schematic from SFI as well. Hope this helps.

Amazingly clear and warm sound.

A couple of circuit board fires.

Although the fires were probably due to the quality of tubes that I was using, it did cost a lot to repair. Besides that, I've loved this thing ever since I got it. I've had a lot of audiophile-type people stop by for a listen and compliment the sound. I'd recommend it to anyone.

Openess, focus, transparency, midrange, ease of use, finish.

Will not drive speakers with that are very hard to drive in tha bass region

A genuinely great sounding amplifier, with smooth yet detailed sound, good focus, and nice top-to-bottom tonal characteristics.
Bass is well controlled, and will only exibit poor control if set up with a speaker with very low impedance in the bass region (e.g. B&W 801 Nautilus).
High flexibilty; can also be used purely as a pre or power amplifier too.
Great fit and finish completes the package.
Highly recommended if you are looking for an integrated in this price range, be it tube or solidstate that interests you most.
Five stars for value as it is the best sounding amplifier at it's price.

Similar Products Used:

Audio Research CA50, Anthem Amp1, Krell KAV-300i, Audion Silver Night 300B integrated,

Huge Soundstage! Wonderful on vocals and small ensembles.

Gets hot. Careful about changing out those Chinese tubes!

I concur with many of the comments others have made about this fine amp -- wonderful sound for the price. But several folks seem to have gone ahead and replaced the stock Chinese 12AU7 tubes in the preamp with something else (NOS perhaps). Be careful about doing this. My Int 1 came to me with Phillips JAN 12AU7s and I was hearing a lot of microphonic ringing. This was very faint and only audible in very quiet passages of music. I listen to a great deal of classical and chamber music -- there is a lot of silence in this type of music and I could occassionally hear this microphonic ringing and pinging. I determined by tapping on the tubes that it was coming from the 2 preamp 12AU7s, so I went ahead and bought a set of GE Goodyear tubes (supposed to be very low microphonically). This did not improve the situation at all. You may not hear microphonics if you listen to "busy" music such as rock or loud jazz which does not have much silence in it.

So finally I contacted Sonic Frontiers. The techie knew exactly what I was talking about and claimed that they had tried all types of tubes in the preamp section and the *only* type that didn't present this microphonic problem was the Golden Dragon (Chinese) tube. Moreover, using this tube would require a small modification of the circuit since the stock circuit configuration is too hard on the Chinese 12AU7 and after about 75 hours the tubes will develop a hissing sound. My unit must have been one of the early ones shipped since I think later ones had this modification performed on them before they left the factory. It's a pretty good bet that if your unit has Chinese tubes in the preamp it's been modified.

Here's a direct quote from an email exchange between me and Sonic Frontiers:

--BEGIN QUOTE--
MY QUESTION:
Second, I'm still not clear on what you were saying about a Golden Dragon 12AU7 being the only tube that will work in this amp. Are you planning on modifying the circuit so that *no other* 12AU7 will ever work in it at all? This concerns me should Golden Dragons become hard to find down the road (indeed, I understand that this company is no longer manufacturing tubes); would I not be able to use a NOS Mullard or RCA? If this is the case, isn't there a major design flaw in this amplifier? Incidentaly, I was able to try a pair of 5814WA GE/Goodyear tubes in the preamp and this had no effect on reducing the high-frequency noise, which leads me to believe that the problem is not microphonic tubes, but a circuit problem (as I think you surmised).

SONIC FRONTIERS REPLIES:
It's very likely that the replacements also squeal.

The existing circuit is too hard on the Golden Dragon. The circuit is modified not to eliminate the squealing, but to accept the Chinese 12AU7. It is the substitution of the tube brand that eliminates the squealing, not the circuit mod.
The new circuit can accept any 12AU7. The Golden Dragons happen to be the quietest. Before we went ahead with this mod, we tried many different brands before deciding on the Golden Dragons. NOS tubes other than military surplus tubes were not an option simply because of cost and availability. They will work, however. Incidentally, the 6189 is very
similar to the 5814. It also made the squealing sound. Thes are military specification tubes that although were built to last, were not intended for audio applications. To give a different example, the 6922/6DJ8 is a tube that we use in many of our products. When it was originally conceived, it was intended for radio frequency applications. Microphonics were not an issue. The JAN/Philips 6922 is the most horrendously microphonic tube I have ever seen. On the other hand, the
Sovtek is the quietest. It is based on the 6H23P Russian military tube which is now made by Reflector. The Russian military version is also microphonic - it produces a ringing sound. Since Sovtek tubes are intended for audio applications, the internal structure is made so that it does not resonate at audio frequencies.

Back to the Int-1, after the mod is done, the JAN/Philips 6189 and 5814 still produce the faint squealing sound with the new circuit. The Golden Dragon does not. Therefore the squealing is inherent in the tube, not the circuit.

Nick Platsis
Technical Support Representative
Sonic Frontiers International

Tel 905-829-3838 ext 240
Fax 905-829-3033

--END QUOTE--

So you have been warned!! Apart from the absence of microphonic ringing I can detect no difference between the Chinese tubes and the JAN Phillips, so I don't know what all the fuss is about with the folks who want to change them back -- I think they've just decided that the Chinese tubes "suck" (as somebody else further down this page says) simply because they're Chinese.

I love this amplifier. It's the best sound that I can afford right now. It cost me an additional $100.00 over and above the purchase price to ship the unit to Toronto for the mod and buy new tubes, but since I bought it used for a good price I feel I still got a good deal.

I'm driving Meadowlark Kestrels (sensitivity is 89db) and it gets plenty lound enough for me. I don't feel that I require more watts.

Incidentally, my amp has the optional phono stage which I use with my Rega P3/Goldring 1042 and this phono section works well for me. I've never had a stand-alone phono stage so I can't really compare it to much, but my records have never sounded finer than they do on this systerm!

Regards,
Brian R.
bwr@rice.edu

Clean vocal, Good value !

Hot

I just brought this two weeks ago, before that I tried several other AV amp like Denon, Yamaha ..etc. Finally, I decide to select this Tube Amp. Although it only give 25 W power, it is powerful to drive my B&W speaker(87dB)to give you a very smooth and clear vocal and reasonaable bass. I have a Denon AV Amp in my living room rated 100W, but I would say this tube amp is much better than my Denon when it play music like jazz, vocal and even Pop. I am very happy with this amp, however once I replace the two chinese make 12UA7s with Mullard 12UA7 it even sound much better.

Build(it's like a tank), velvet sound,

none for me

This is the best amp i've ever used. The sound comes out from this lovely machine like thick velvet, sweet & smooth.
The lack of power at extreme high levels of volume is not a weakness for me. It is strongle recomended to anyone wants to buy an int-amp within this price range.

My system is :

Speakers: Triangle Antal XS
CD Player Creek CD-53
Interconnect: Siltech
Speaker Cables: DNM Reson
Room : Approx 110m2

Similar Products Used:

marantz pk80II SE

I have gone through an upgrading process with my budget system which started out as Optimus Pro LX-4's, an NAD 304 Integrated Amp, a Rotel 970-BX CD player, Kimber PBJ and 8TC cables, and black diamond cones under everything. I had purchased a pair of Impact Technology transmission line speakers from Bob Cohen of The Cable Company/Ultrasystems fame and realized that these new speakers were revealing problems with my amplification. I want to tell you all about the amplifier I purchased to replace my NAD, the Anthem Integrated 1. It's a 25 Watt push-pull integrated made by Sonic Frontiers which uses 2 sets of 4 Sovtek EL84's in the output and 2 matched pairs of 12AU7's and 1 12AT7 in the input. First impressions were good, the amp had more power, more bottom end, more AIR, a wider, bigger, more defined soundstage, more detail and more smoothness. The pace was somewhat slowed I felt and I will return to this. The bigger problem was a stridency which was unexpected. I felt the highs were strident even though they were more liquid. I suspected the Chinese made 12AU7's which were used at one of the 2 pairs. The other pair was some Jan Philips. So, I replaced the Chinese tubes with some RCA's and left the Jan Phillips alone. Gone were the strident highs. More smooth overall, maybe too smooth?? I also later changed out the stock 12AT7 in favor of a Mullard. Better yet. (Don't listen to the SF techies who claim that the stock tubeset is the best for the preamp section--bullshit!! The Chinese tubes suck!!) Later on I switched from Kimber to Tara Klyma and Synergistic Research Sterling Alpha. The Alpha interconnects were superior and brought back some of the speed I mentioned before. The Tara's were smoother overall, yet not as bass intensive, nor quite as revealing as the Kimber 8TC. I say it's a toss up there on cables. Now as far as the Integrated 1 was shaping up, I was having a good time with it. It's a system which can be converted from integrated configuration to either preamp or amp by making a simple snipping of two internal wires. The internal wiring is kimber anyway, so go get yourself a pair of PBJ's and snip away. You can use the PBJ's to externally convert the separated component back to its original integrated form. (Strange as it may seem, I got better sound with the .5 meter PBJ's hooked up post snip) I mention this feature of the unit because it allows you to evaluate the sound of each part separately and it also allows for you to upgrade without trashing your entire amplification system completely. With tube upgrades in place, the amp section I felt was still the better section. There was plenty of power, punch and volume to work quite well in my 15X13 room and with three different types of speakers: the transmission lines, the Optimus's, and the KEF Q20's which I borrowed. This is for sure a good amp mate for transmission line speakers. As far as the preamp goes I'd say it's pretty good, but not hands down better than the preamp section on the NAD 304, so if I were buying the Integrated, I'd look to upgrade the preamp section first. I would also expect the preamp of the Anthem Pre 1-L to be superior. However, it's good enough with the tube upgrades I mentioned that you'll appreciate the synergy of the two sections well enough that you won't want to go looking for a better preamp for some time. And if you do go looking, try a passive that's cheap but good like the Purest Sound Systems stuff or the Creek line of passives, which are less than $500. The amp: A- the Preamp: B+ The Integrated: 4 Stars.

After listening to the range of mass produced solid state junk, the only thing that truly impressed me was the Naim nait-3 integrated (Which I Still inted to get, someday). Arcam (aplha 8 & 9) were just not enough overall to justify a 1000-1300 dollar outlay; little definition but smooth. Rotel was just too harsh and not really musical. Then I found the Anthem integrated 1. An amazing little thing! 25 watts of class A/B tube sound. I was expecting rolled off highs and lows, but what I found was a solid, albeit slightly under powered at times bass foundation, but oddly only on certain rock tracks. Kick drums don't have the attack of good solid state stuff, but bass guitar and timpani and the like shake the hell out of my room. (??) At the retail price of $1400 Canadian, better can be found, if you like sharp/clean music. But finding this thing barely used at $900, I went for it. The soundstage it presents would make you think you were listening to a Krell or Classe', without the intense bass impact. As far as "budget" tube amps go, this thing is wonderful. It just makes beautiful music. Just make sure your speakers are fairly sensitive, and this thing will sing.5 stars for overall sound, but for out and out power and bass, 4 stars.