Radio crftmen C500a amplifiers

After 4 months of waiting, I have finally managed to find a fully restored Radio craftmen C500a amplifiers to accompany my 12.1, MC240 & WE KS16604.

Some backbround information on the RC500 from Alan (Pilotrol) at R33 net:

Radio Craftsman founded by John Cashman in47. John Cashman worked in Hallicrafters Radio Company before he founded Radio Craftsman. Radio Craftsman was mainly focusing on development of home audio and television from late 40 to late 50's.

Ed Miller and Sid Smith were two major engineers to work for Radio Craftsman during early 40's - mid 50's. Actually, Ed Miller is the founder of Sherwood and who leave Radio Craftsman before 1953 (This year he founded Sherwood and mainly focused on integrate amp and receiver). Sid Smith later left Radio Craftsman and joined Marantz as chief engineer in 1954.

The major audio products from Radio Craftsman actually was not completely developed by Radio Craftsman, but mainly licensed by RCA and Western Electric!

Most of the Radio Craftsman gear sound fast, clear and very transparent with fine body (thin but not thick and mellow body).No question that the most popular Radio Craftsman amp in the family must be the C500 series.

The first two generations of C500 was mostly worked by Sid Smith and licensed by Western Electric. The first generation C500 was introduced in 1951, it comes with a smooth corner Stancor output transformer. In 1952, smooth corner version replaced by the sharp corner version output. Radio Craftsman C500 is based on Williamson design which operated with 2 x KT66 output tube in triode but pure class A operation with 10 watt output. It has very natural sweet, clear and transparent tone. However, it has very clear, natural, realistic and transparent tone than many vintage and modern hi-fi amp.

The Radio Craftsman C500 was replaced by C500A in 1953 and the same years Sid Smith left Radio Craftsman. I believe the Radio C500A is the final work of Sid Smith. The different between Radio Craftsman C500A is it has much higher plate voltage in triode class AB and the output increase to 15 watts per channel. It also has much large size choke than C500, it also licensed by Western Electric as well. The rectifier tube also changed to 5U4G instead of 5V4G.

The final version is Radio Craftsman C550 and it replaced Radio Craftsman C500A in 1954. Honestly, the sound of Radio Craftsman C550 sounds slightly different than C500 and C550A, it has better body but not as transparent sweet and natural than C500 and C500A. The reason is simple, the C550 is operated in Ultra-linear instead of triode operation, the output also increase to 30 watt instead of 15 watts. The amplifier also used a B+ delayed turn-on via a slow warm-up, it required 60 seconds to preserve the cathodes on the KT-66s. FYI, Radio Craftsman C550 was not designed by Sid Smith, but actually designed by Bob Grodinski, this guy took over Sid smith work as Smith already left the company and joined Marantz in summer of 1954...!

Even though, my intention is not to "collect" vintage tube amplifiers for the sake of collecting, I have subsconsciously been poisoned by the music reproduction from these KT66 amps.

Out of the 5 amplifiers mentioned, I have managed to find 3 & 1/2 namely:

1. Leak12.1
2. Radio craften C500
3. Mcintosh MC240
4. WE KS16608 (the model after the highly priced WE 124) -- just joking! : )

Hopefully, I can find the WE 124 to replace the WE KS16608 soon!

Top five best sounding 6L6 power amplifier

According to a Hong Kong tube amplifiers magazine, these are the 5 best sounding 6L6 vintage power amplifiers.

Even though the various opinions are very subjective, I have the opportunity to listen to (1) to (4) namely : 12.1, Mcintosh MC240, Quad II & Radio Craftmen C500 and there are indeed nice sounding power amplifiers using 6L6 or KT66.

With the exception of 5) Western Electric WE124 (as I have not have the opportunity to audition), my ranking of the 4 amplifiers are as follows:

Ranking (from top) Best match pre-amplifiers using my current M7 or Fisher 400CX:
1. Leak 12.1 - warm sound, good soundstage, detail and full of "inner enegrgy". Best match with Fisher 400 Cx pre-amplifier
2. Radio Craftman C500 - smooth sound, good soundstage, sound slightly faster, good balance. Best match with Marant 7 pre-amplifier
3. Mcintosh MC240 - good for representing music with energy, good power and yet still able to maintain its warm smooth sound. Best match with Marantz 7 pre amplifier
4. Quad II - overall warm and balance amplifier, soundstage not as large, power may not be enough for low sensitive speakers. Best match with its own Quad pre-amplifier.

Simple set up

After my spring cleaning, these are my current system. My dream amplifier now is the Western Electric 124 . However, the price of it is so high (HKG$100,000 - 140,000) is making think twice. : (

Hopefully, I will be able to find one pair one day.

Tubes and wires upgrade

I have been concentrating on the search of the hifi equipements for a while and I have finally settled with the one I like namely: Leak 12.1, WE KS16608 and Mcintosh which uses the 6L6 or KT66 tubes with Marant7 & Fisher 400CX as preamplifiers. Both the Pye Mozart & RCA speakers were sold to other audiophiles.

Now, my next move is to look at improving the other areas such as the changing of tubes and getting proper cables to further enhance the sound.

Yesterday, I have managed to get a Quad set of vintage Brimar 6L6G tubes to replace the previous Groove 6l6GE and the 5881 in my Western electric KS16608. Immediately, the sound became much more smoother and filled the soundstage with more details when using the Cora Beta 8 full range speakers..

Knowing the important of the speakers cables, i have ordered a pair of Artist speakers cables to replace my existing one.

Perhaps less is more as I could concentate on my improving my current set up... : )

My current hifi collections

I have not intended to start a collection of vintage amplifiers as my intention is to use the equipements to reproduce the music that i want to listen. However, my hifi journey and my various exploration has led to a proliferation of hifi equipments as follows. I feel quite priviledge to be in Hong Kong - the heaven of vinatge hifi and having the opportunities to audiyion various types of brands and its different music reproduction.

As music is about personal preference, there is no such thing as teh perfect or best amplifier. Only the "best" in term of personal taste. There are occasions, however, a certain hifi that could capture more audiences attention and preference such as the WE, Marant 7, Leak 12.1, fisher 400Cx, Mcintosh MC240 etc.

• Power amplifiers
• Leak 12.1 (using KT66 tubes) - my favourite and most loved amp as it took much efforts to pair them up & restore. To keep for life!
• Mcintosh MC240 (using 6L6GC tubes) - my first serious vintage amp!
• Western Electric KS16608 (using 6L6 tubes) - found in Singapore & restored in Hong Kong ! One of the best sound after restoration to its original condition!
• Siemens Smf4vb (using El84 tubes) - 5 watts single ended amp to match my Cora Beta 8 full range speakers

• Pre amplifier
• Marantz 7 - One of the best preamp to keep!
• Fisher 400 CX - Second best preamp to keep!
• Speakers
• Tannoy Canterbury monitor red - Most relaxed speakers!
• Rogers LS3/5a - one of the must have classic!
• Coral 8 Beta fullrange speakers - most detailed speakers!

Coming soon: Pye PF91 (to buy or not to buy?) & Radio Craftmen C500 using KT66 tubes

I hope to do some spring cleaning in July 06 and further streamline my collection to a more manageable level as I am running out of space in my Hong Kong apartment. After much listening, I have sold the following to other audiophiles collectors:

• Pye Mozart using EL34 tubes
• RCA full range speakers

Do write to me at maxbliss888@yahoo.com.sg should you find any interest in my hifi collection.

Fully restored Western Electric KS 16608

I have just received my restored Western Electric KS16608 amplifiers. It sounds fantastics!

My Western Electric amplifier is restored by 毅德音響 ARTIST HI FI CO Sifu Mr. 梁文光 Marco. For detail, please see :

http://www.wowhififever.com/KS_16608/WE_KS_16608.htm

The Western Electric KS 16608 (KS = Kearny Specification, a New Jersey subsidiary which supplied replacement parts for WE) was the model after the Western Electric 124. The KS16608, in my opinion, has been seriously under rated. Even though the price is very affordable and cheap, the sound is fantastic! Some so called "experts" has looked down and condamned on these amplifiers. However, the key questions are: Have they audition a perfectly working set of amplifiers or a non performing ones to judge? Have the amplifiers been properly matched with the proper pre-amplifiers and speakers?

They are many reasons why the WE KS16608 is such a wonderful amp to "play".
1. 以價錢論聲可算超值到難以置信。
2. The 6L6 tubes are very resonably priced when comparing with the Kt66, KT88, El34 tubes.
3. The KS 16608 is the model after the WE124 and is 按西電的要求特性交由其他廠代造 (Contract manaufactured)

Siemens single ended SmfV4b amplifiers

Siemens 5 watts power amp together with my Marantz 7. The Siemen amplifiers are very well built, with solid chassis and very neat internal circuit and wiring. However, there is a need for some by-passing of the pre amplifiers in order for it to sound good.

My friend David, therefore, went to consult his DIY friend in Germany. Within days, a set of simple instruction was sent. After performing a" by pass" operation (sound like real life operation), the sound from the 5 watts Siemens are exceptionally good! What a change!

For a mere 5 watts power amplifier, see how big the output transformer is! This big output transformer may be the secret as to why the sound of Siemens amp is so good....even with the difficult to drive, low sensitivity LS3/5a speakers!

The Siemens amplifiers with its low watts output is able to work very well with high siensitive speakers such as the Tannoy. the clearity of music and the ability to reproduce real life music really differentiates these amplifiers from the other low powered amplifiers!

For an understanding of German amplifiers, please visit: http://www.tube-classics.de/TC/Klangfilm/Klangfilm.htm

Pilot SA232 & Siemens SmfV4b amplifiers

The Pilot SA232 has always been an odd one out among my hifi equipments.

My Leak12.1 matches very well with my Fishers 400CX + Tannoy Canterbury. My MC240 + Marantz 7 + LS3/5a combo is another perfect match, In the bedroom, my Pye Mozart keeps my RCA full range speakers company.

The Pilot Sa232, therefore, is like a spare waiter at a wedding banquet trying to find a role to play. This has prompted me to put in on sale at R33.

Upon getting the Coral 8 inch Beta speakers, I immediately plugged in the Siemens SmfV4b (without by-passing the pre amp ) and the hum sound has prevented me from enjoying the Cora.

Without much choice, I have to hook it up with the Pilot SA232 and immediately I was surprised by the very nice vocal reproduction together with the Marantz 7! The Pilot has finally found a plane to fly!

In Hong Kong, the hifi circle is very small and yet can be very political at times. Very often, conflicts arises as a result of competition for the same equipments or when one wants to impose one's views upon others. Sometimes, conflicts also arises out of envy and the inner desire of wanting to win, all the time.

I have my fair share of exchanges in the forum. These has prompted me to keep a low profile in the forum and let the various "opinion leader" continue to dominate the various threads and "blow water" for their own ego or vested interest. However, there are some nice fellow audiophiles such as JK who is always willing to teach and help!

In the end, listening to hifi is the enjoyement of music. The various equipments basically help to reproduce the sound that suits the individual taste.

The night is quiet..and the music is singing softly from the coral and the Pilot. Enjoy music : )

Artist hand made interconnect cable

Having been working in the brand building business for a long period of time has made me developed a liking for well established brands with consistent quality as well as clearly defined image and brand positioning.

In my journey of hifi, my main concentration has been on acquring quality vintage items and restoring it with the original, NOS,or best parts availables. Very little attention has been given to the quality of the tubes and the various interconnect cables.

I was planning to buy a few pair of audionote or some other braned interconnects for my hifi but the prices are so high that it often made think more than twice.

Yesterday evening, while I was sending my Western Electric 16608 for servicing and restoration at 毅德音響 ARTIST HI FI CO , I came across a " not so attractive looking" and non branded interconnect. Out of curiosity, I have asked Sifu 梁文光 Marco what is so special about the cable. To my surprise, Sifu mentioned: 訊號線就是選用了德國錄音室所用的純銅線芯為線材，RCA插頭亦係採用德國古老製品. Since the pure copper wiring is old stocks of wiring cables being used in the studio in Germany, the quality must be exception. Moreover, the sifu also offered a return policy of less 10% if the results is not satisfactory. So, I bought a 1.2 metres cables at HK$1500.

Immediately, when I reached home, I pugged in the interconnect and awaited anxiously to listen to the reproduction of sound. Yes, this "not so good looking cables" actually managed to lift up the sound of my exisiting system by threefold ! It is really a value for money cables! I am sure the interconnect will be even better after 10-20 hours of running in. No wonder there is a saying: Never judge a bok by its cover! In this instance, never judge a cable by its look! Ha ha ha!

When I am back at the shop to collect back my restored WE, one month later : ( ...yes it takes one month, I am going to get another pair of the Artsist hand made cables!

Cheers

Western Electric Dream

I have managed to get some information on the WE over a forum by Alan (Pilotrol):

When Western Electric was forced to break up in late 40, some of the production license of Western Electric had been sold or assigned to Altec, Langavin and IPC. Western Electric has been designed many amp for lab, PA or telephone use during 50's, but they were no longer produced the amplifier for own use.

During mid and late 50’s, Dukane and McIntosh were assigned to produced WE design amplifier for Western Electric. In fact, The Western Electric KS-16608-L1 is a 12 watt output mono amp with 6L6 PP design by Western Electric but produced by Dukane Corporation in 1958. Large amount of KS-16608-L1 had been produced during late 50’s to early 60’s. The KS 16608s are the major model to replaced the WE124 for PA or Line amp during this period. FYI, Dukane also has produce KS-16617-L1 (6V6 pp at 8 watts) and KS-16610 (6550 PPP at 75 watts?) during this period.

One of my KS 16608 was produced by Dukane in Illinois & the other one by Mutiplex West Poplar Montana. Since I could not afford or find the more famous and expensive WE 89 & 91, the WE KS 16608 is a good substitute to satisfy my desires for a pair of vintage Western Electric amplifiers!

According to some so called "expert", the sound from this KS 16608 is horrible but I disagree totally! Good music not neccessary comes from only the WE 89 or 91. If this set is horrible why should the Japanese audiophiles continue to pay to own this?

Nevertheless, to ensure perfect sound and to bring the amplifier back to its glorious days, I have sent my pair of WE KS16608 to the famous Hong kong hifi writer and 毅德音響 梁文光 Sifu for restoration and changing of capacitors, resistors and wiring this evening as I could not find the schematic. I am now anxiously waiting for the return of my WE 16608 and the start of the Western Elecric dream!

: ) Be Happy!

Western Electric amplifier 16608L1

The WE amplifier is so rare and expansive than I have never dare to dream of finding or owning a pair.

During my trip back to Singapore, I was fortunate to have met up with Ace who has told me that there is one pair at a junk(old) hifi shop near Sungei road in Singapore.

It was raining very heavily that day and it took me a long time to find the shop. Unfortunaley, the shop was closed as the owner Mr.Lim was out. I have waited for more than one hour and the owner still has not returned. Without much choice, I have decided to go back to try my luck after dinner.

After dinner with my family, I have decided to go back to the junk hifi shop to try my luck. This time, the owner was in. Initially, the owner was reluctant to bring the set out as it was "buried" deep in his shop as his shop was packed with old hifi & speakers. After much persuasion, he has finally agreed to bring it out. I was so eager that I have helped him to bring it out and by this time, he was more willing to show them to me and even decided to let me audition the set.

Both the set were in working condition and I was so delighted that I quickly went to the ATM machine to draw cash and paid him immediately. My next task is to bring them back to Hong Kong for cleaning and tidying the interior wiring system.

Sometimes, when you are least expected, some nice thing appear! The Western Electric amplifier is now sitting nicely at the shelf. It was a real pleasant surprise. Morover, the set was using the 6L6 tubes similar to my Mcintosh MC240. I believe the sound will be even better when it is being played with my Fisher 400CX pre-amplifier (as during testing it was played direct without any pre-amplifer) : )

I have wanted to learn more about the amplifiers that i own. Thus, I have started a Western Electric KS 16608 forum hoping to get more information on the amp. In fact, I get more then what I have asked. Some "audiophiles" were so critical that they started criticising the amplifiers just because it was not the famous WE 89 or 91 models....

How sad! Just because it is not the most sought after WE amplifiers will be branded as not a good amplifiers? For me, I like the amp alot as after so many years (from 1960s) it is still singing beautifully was a USP itself. Moreover, it is found in Singapore, my home town. According to the seller, he has owned the amplifiers for more than 15 years..which is a long time, in my opinion.

Perhaps, the world will be more peaceful if one can be more tolerance and appreciates things from a different angles and a bigger heart to accept differences in taste and preference.. instead of wanting to win all the times and imposing views and opinion onto others...

: )

Next KT66 amplifiers

After listening to my favourite Leak 12.1 using the KT66 tubes, I was totally poisoned by the wonderful sound reproduced using the magical KT66. These has promted me to search for another amplifiers using the KT66. Immediately, the Quad II came into my mind. However, after having experiencing 2 set of Quad II, I realised that Quad II has very nice sound. However, after AB comparison, I have always found that Quad II has some small limitation which is difficult to describe.

Thus, my next amplifiers will have the following characteristics:

1. Made in UK
2. Mono Block having about 12w -15W
3. Using KT66 tubes.

Given the above characteristics, the options available is Pye PF91. Very little information is available on the Pye PF91. Pye PF91 is a KT66 push pull amp. There is another Pye HF 25 but the Pye PF91 KT66s are triode connected, so the amp gives about 12W while the Pye HF25 is 25 watts.

Higher watts power is not something I am chasing. Some experts have mentioned that the Pye PF91 does not sound as good as the Leak12.1 and I am curious to do am AB test and find out. I was told that Pye company was formely producing equipments for military use. Given the high standard required for military commissioned equipments, I am quite confidence that the Pye PF91 will be of a high standard.

In my wish list, I hope one day I can build a power amplifiers collection consisting of 1.) Mcintosh MC240, 2) Leak 12.1, 3)Pye Pf91, 4)Radio Craftmen C500, Western Electric amp using 6L6. I have geard that Tannoy and Roger Williamson made very good KT66 amplifiers but I have yet to hear them. Thus, the search is now on..

Best Hifi combination

"Playing" with Hifi can be a very sentimental and emotional hobby. Very often, we can see much arguments and quarrel over the various hifi forum owing to personal views and perceptions plus the fact that there are many monetary factors involved.

For me, it is only a hobby. I have change my hifi equipemnt very often. During these peiod, I have let go Elekit iintegrated amplifier, Fisher 80c, Leak 10, Quad II twice, Thorens TD124, Thorens TD160, Altec 604E speakers.

Why? The reason is not because the items are no good but due to personal taste preference. I like Leak 12.1 alot owing to its great warm sound, great sound stage as well as details plus the KT66 tubes.

For me the best combination A consists of Leak 12.1 + Fisher 400CX + Tannoy Canterbury.
In addition, I like Mcintosh MC240 + Marantz 7 + Rogers LS3/5A
For bed room, I think the Pye HF20 Single ended with the full range speakers are the ideal combination.

There are many hifi collectors in Hong Kong. Some specilaised in Marantz & Mcintosh, some in Leak, some in Eico. For me, since space is a constraint, I am very happy and contented with the above set that I have. The Pilot SA232 using the EL84 suddenly become a lonely child as I could not find a pre-amplifier to match it.

In fact, I have listened to my Leak 12.1 + Fisher 400CX + Tannoy so often that the rets are on the shelf over the past months.

If anyone ask me for my opinion, I would advice one to go for "one" very best set rather than having so many "average" sets. Moroever, my preference is not to have too many set of the same or similar items which is why I sold off 3 set of LS3/5A and kept one for reference and use. IMHO, all the LS3/5A has very coomon characteristics (i.e Good mid) ireegardless of the brands.

Thus, since wants are unlimited and resources are limited, rather than spending all the budget on one kind of speaker and one kind of sound, my prefernce is to go for one large speakers (12 inch & above) ; one LS3/5A for pure vocal listening and one full range speakers.

By having these 3 kinds of speakers, we can enjoy full Orchestra music with the large speakers, light jazz and vocal for LS3/5A and use the full range for pure vocal and pure violin or one instrument.

Hifi, is means for the reproduction of actual music to our ears. Since there is no one single speakers that can satisfy all our requirements, one has to know what type of music one likes. Like what they say, one man's food is another man's poison.

Enjoy your music!

Further restoration

I was quite free during the Easter holiday period as I was alone in Hong Kong. With so much freetime, it has prompted me to further upgrade my 220 v Leaks 12.1 set.

With the spares resistors and capacitors, I was able to get into the restoration quite quickly.

To ensure that the set is properly restored, I always make sure I use the other set as reference so that the correct position.

It is important to make sure that the TCC capacitors does not leak as it does, it will send in extra current towards the tubes which will shorthen the life span of the tubes.

The 12.1 is relatively maintainance friednly as the British made amplifiers tend to have very neat schmatics positioning.

With the help of JK, I have managed to learn do some basic maintanance works which help to keep the amplifiers in its prestine condition. Thanks John!

DIY Speakers cabinet

I was impressed by the RCA full range speakers which reproduces excellent vocal !

This has prompted me to find a pair of 1950s full range 8 inch Telefuken spekares units and try to DIY a open baffle speakers cabinet.

I was fotunate to be able to find a open baffle plan from a fellow R33 audiophiles.

Next is to serach for the materials and cutting the wood according to the plan size.

After several days of hard work, it was finally completed. Tonight, the last bit was to paint them with wood colour.

Finally, everything was done and the satisfaction is beyond words can describe.

The muisc from the speakers in the open baffle cabinet is nice and the speakers are standing in front of the Tannoy!

Next target is to look for WE 755a?

Resistors as spares for Leal 12.1

As part of my learning of DIY , I have stocked up some vintage Allen Bradley resistors for future usage in addition to the NOS TCC capacitors.

The serach for these are time consuming but I am glad I have the help of a fellow audiophiles JK, who is helpful in teaching as well as sharing his expperiences.

The hifi journey has been an exciting. one There are some audiophiles who are very helpful and nice while there are those who are out to make money...

Leak 12.1 : Changing of capacitors & resistors

After listening to my 12.1 for a while, I began to realize that there are some hum sound coming from my Tannoy Canterbury, a pair of sensitive speakers, when the muisc CD stopped playing. Some has said that it was due to the nature of the sensitive speakers. When used with the LS3/5a, the hum sound dissappeared.

Being a perfectionist, this "hum" sound has promted me to to try to "fix" the issues. I have tried sending these to the hifi repair shops at Ap Liu street Sifu but after adding an extra capacitor (quite an ugly site), and paying much $$$ the hum sound still exists.

Next, I have tried another Sifu to fix the hum sound, which resulted in changing of 3 resistors. The Sifu has managed to get rid of the hum sound which was quite a joyful thing. When I invited my friend JK to my house for audition, he has realised that even though the set was very quiet, the sound from the 12.1 has been modified and musch details has been surpressed. Upon checking, we realized that the 3 resistors replaced were not excatly according to the values set by the schematics. Thus, a third round of restoration process has started again. Lessons learnt the hard way.. My body must be getting fitter after carrying more than 30kg of hifi equipments up and down the apartments...

Finally, with all the 3 resistors being replaced with the correct values, the leak 12.1 is back to its original sound with much more warmness, soundstage and details.

From then on, I have bought the neccessary meters and tools for DIY. I was able to find 4 units of NOS 25uf TCC capacitors and this time, I have managed to change the capacitors myself.

Now the 12.1 is singing beautifully! I have recently found 3 more 0.25 uf TCC super metal packs capacitoirs and 7 more is on its way. I hope they could arrive soon as I would love to use the 1st May holiday to DIY both my set of 12.1...

The joy of listening to the music is nice and the DIY restoration process is also a nice way of relax and de-stress after a hard days work!

Pye HF S20 Mozart Pre amplifier

The Pys Mozart amplifier comes with its own pre amplifier.

The pre amplifier has a very attractive bronze mirror like front plate. It uses the 2 ECC83 tubes and is very small in size.

Set up is easy as it has two code which connect the pre-amplifier and the ppwer amplifier.

The next step is to DIY the woden boxes this week end!

Pye HF S20 Mozart EL34 single-ended amp

April 2006:

To find a suitable amplifier for my new RCA full range speakers, I have started the search once again.

I was told that the full range RCA speakers will be best driven by a 300B amplifier or a 2A3. Unforunatley, the vintage Western electric 300B amplifiers are expensive and the 2A3 amplifiers are hard to find.

Without much option, I have decided to try a single ended amplifier - the HF S20. It is a stereo version of the HF10M, using one power transformer to power both the left and right channels. The amplifier looks odd, as the EL34s are mounted horizontally rather than the normal vertical arrangement. This is the firts time I am using the single ended amplifiers as my previous amsp were push-pull.

The amplifier is in its original condition which needs a thorough cleaning... This will be my project for the night....

RCA full range speakers

March 2006:

I have recently bought a pair of 1950s RCA vintage full range speakers. The shape of the speakers has captured my attention as it has very nice curve.

The sound from the 6 inch full range speakers is limited but it is excellent for vocal repoduction. I was using my Leak 12.1 to push the speakers but I was told that smaller amp is much better for it.

So I have bought a Pilot 232 and the sound is excellent.

Does anybody has more history on the speakers as I could not find much information on the net?