Makes good karmic sense to me.
Really takes them to another level.
jeff
Not only do I still have the F120a, I have purchased a Dynakit ST-35 tube amp kit, which I am about to build. After MJK brought over his tube amp and revealed the true nature of the F120a, I decided to keep them. Initially I bought a little Miniwatt S-1 (2.5 wpc), which sounds great with the F120a--except it doesn't have the power do play music with significant bass at anything beyond a polite SPL. I also found that my old Sansui 350A receiver (cap. coupled SS) works pretty well, but not as sweet as the tubes.
Since the 25 wpc of the Sansui 350A seemed to be more than enough for me, I chose the ST-35 for its sound qualities. Other folks with larger rooms and/or aspirations of hearing damage might want more than the 17.5 wpc provided by the ST-35, but it should be sufficient for my purposes.
Cheers, Jim
During all that follows remember that most of mine (& Chris') listening is with drivers that have been matched & treated.
Warning: long stream of conciousness follows.
Depends. Room, box, amps, taste are all factors. For awhile MA was pulling ahead, then Fostex revised both their main lines. They each have their strengths. If you have a small SE tube amp, the efficiency of the xx6En drivers give them a big edge.
A couple years ago i sent Mark a set of uFonken because the FF85k was trouncing the Alpair5 and Alpair6. I set him a goal of getting better than the FF85K with the next generation.
A recent 3" shootout had both the A6.2p & m did out perform the 85k -- kind of amazing given how good the driver is-- but Fostex hadn't stood still and the new FF85wk is neck & neck,
http://www.diyaudio.com/forums/full-range/196061-3-driver-audition-fostex-mark-audio.html
I have never been a big fan of metal cones. Including the 1st gen Mark Audios.The 2nd gen with the unique multiform cones changed that. The Alpair 7 became my favourite driver. The A7.3 is even better (at the sacrifice of a small amount of bass extension). But the EL70 (CSS but made by Mark Audio) is not far behind, with more robust & more extension in the top end, a more relaxed sound, it doesn't have the downward dynamic range but one of the side effects of that is that it is not as ruthless revealing deficincies of the rest of the system including the software -- if you need to rock, or have an HT receiver i'd put the EL70 over the A7/A7.3.
The new FF125wk is right up there in contention (stock vrs stock, 1st treated ones haven't been listened to yet, boxes not yet done)
The Alpair6p does, IMO, give a vinatge sound with a laid back top good midrange and bass that is very unexpected from a 3" (mind you a large one). The CHP70 is not a driver i have heard (Europe & Japan only) . It gets high marks -- check out the accolades on the audioTalkforum -- and is broadly similar to EL70 and of the same time frame (Zia, the only guy i know that has both -- the guy is a recent over the top addict and proud of it), gives the edge to the EL70. The new CHP-70.2 (with gen 3 tech), Mark took the desires of people to have a more vintage sound, and ended up with something i personally feel was a step backwards (look at the FR charts to get a broad idea, big peak followed by deep shelf down). By itself it sounds just fine. Set it side by side with EL70 or A6p and it becomes clear that something is missing -- top harmonics in female vocals for instance. In the milliSize boxes we did this comparo in the A6p is actually the winner, the EL70 sounds a bit constrained -- put it into the larger box that it is happier in and it is clear that it is.
Now, to muddy things further. We developed the microTower as a tribute to Winslow Burhoe. It was always my intention tp eventually convery the microTowers we built to microTower IIs (ie add tweeters to the unused sides). With the CHRs in them originally this would be a receipe for HF pain. With the CHP70.2 the shelved down top can be turned to an advantage here making the MT II make more sense. It would also make sense with some amps, or rooms that are real "bouncy/live"
So it depends ... all these drivers are marking a time when FRs are finally starting to eclipse and improve on the best from the times when FRs were king.
Don't let buyer paralysis take hole, buy something and start playing. Compared to multiway systems they are cheap (money wise, not quality wise)
Questions? Did that make sense? (probably not completely
dave
Thanks dave it helps alot.jm
During all that follows remember that most of mine (& Chris') listening is with drivers that have been matched & treated.
Warning: long stream of conciousness follows.
Depends. Room, box, amps, taste are all factors. For awhile MA was pulling ahead, then Fostex revised both their main lines. They each have their strengths. If you have a small SE tube amp, the efficiency of the xx6En drivers give them a big edge.
A couple years ago i sent Mark a set of uFonken because the FF85k was trouncing the Alpair5 and Alpair6. I set him a goal of getting better than the FF85K with the next generation.
A recent 3" shootout had both the A6.2p & m did out perform the 85k -- kind of amazing given how good the driver is-- but Fostex hadn't stood still and the new FF85wk is neck & neck,
http://www.diyaudio.com/forums/full-range/196061-3-driver-audition-fostex-mark-audio.html
I have never been a big fan of metal cones. Including the 1st gen Mark Audios.The 2nd gen with the unique multiform cones changed that. The Alpair 7 became my favourite driver. The A7.3 is even better (at the sacrifice of a small amount of bass extension). But the EL70 (CSS but made by Mark Audio) is not far behind, with more robust & more extension in the top end, a more relaxed sound, it doesn't have the downward dynamic range but one of the side effects of that is that it is not as ruthless revealing deficincies of the rest of the system including the software -- if you need to rock, or have an HT receiver i'd put the EL70 over the A7/A7.3.
The new FF125wk is right up there in contention (stock vrs stock, 1st treated ones haven't been listened to yet, boxes not yet done)
The Alpair6p does, IMO, give a vinatge sound with a laid back top good midrange and bass that is very unexpected from a 3" (mind you a large one). The CHP70 is not a driver i have heard (Europe & Japan only) . It gets high marks -- check out the accolades on the audioTalkforum -- and is broadly similar to EL70 and of the same time frame (Zia, the only guy i know that has both -- the guy is a recent over the top addict and proud of it), gives the edge to the EL70. The new CHP-70.2 (with gen 3 tech), Mark took the desires of people to have a more vintage sound, and ended up with something i personally feel was a step backwards (look at the FR charts to get a broad idea, big peak followed by deep shelf down). By itself it sounds just fine. Set it side by side with EL70 or A6p and it becomes clear that something is missing -- top harmonics in female vocals for instance. In the milliSize boxes we did this comparo in the A6p is actually the winner, the EL70 sounds a bit constrained -- put it into the larger box that it is happier in and it is clear that it is.
Now, to muddy things further. We developed the microTower as a tribute to Winslow Burhoe. It was always my intention tp eventually convery the microTowers we built to microTower IIs (ie add tweeters to the unused sides). With the CHRs in them originally this would be a receipe for HF pain. With the CHP70.2 the shelved down top can be turned to an advantage here making the MT II make more sense. It would also make sense with some amps, or rooms that are real "bouncy/live"
So it depends ... all these drivers are marking a time when FRs are finally starting to eclipse and improve on the best from the times when FRs were king.
Don't let buyer paralysis take hole, buy something and start playing. Compared to multiway systems they are cheap (money wise, not quality wise)
Questions? Did that make sense? (probably not completely
dave
Current Mark Audio drivers are A6.2, A7.3, EL70, A10.2. I have 1 pair of A12, and a number of CHP70.2 on special. CHR70.3 by special order (for what i have to sell them for treated i'd suggest buying a set of stock A7.3)
Fostex FF85wk, FF125wk, FE126En are/willbe regular stock. Others can be special ordered.
dave
Hmm, I missed a F120A thread...
I tend to agree, the F120A is still my favorite small Fostex driver and I have the FX120 as well. While there is much in common between them, the F120A wins hands down, low-level detail is much better IMHO. I don't own a solid-state amp so I can't comment on using one with them.
I have an original Miniwatt... I did some actual tests and found the specs to be quite poor. With an 8-ohm load they won't even manage 1-watt per channel. They do perform better into a 16-ohm load, don't have much of anything below 100Hz and distortion was pretty high IIRC. Regardless, so many people tend to like them... I even hooked them to a pair of Hornshoppe horns. I just don't care for it, but hey, what do you expect for $250?
I've had about 6 Stereo35 amps over the past 25 years and still have 3 plus parts. Nice little amp actually but if you build it with stock circuitry they are prone to run hot, very high B+ and tend to smoke an output tube once in a while. I would suggest separate cathode bias resistors and bypass per channel and beef up the supply a bit. I also prefer the 7189 tube over the EL84. Not for sonic reasons but they have much higher voltage ratings and seem to hold up better in the 35. Overall, a nice sounding little amp. Post some pics when you can.
Regards, KM
I tend to agree, the F120A is still my favorite small Fostex driver and I have the FX120 as well. While there is much in common between them, the F120A wins hands down, low-level detail is much better IMHO. I don't own a solid-state amp so I can't comment on using one with them.
I have an original Miniwatt... I did some actual tests and found the specs to be quite poor. With an 8-ohm load they won't even manage 1-watt per channel. They do perform better into a 16-ohm load, don't have much of anything below 100Hz and distortion was pretty high IIRC. Regardless, so many people tend to like them... I even hooked them to a pair of Hornshoppe horns. I just don't care for it, but hey, what do you expect for $250?
I've had about 6 Stereo35 amps over the past 25 years and still have 3 plus parts. Nice little amp actually but if you build it with stock circuitry they are prone to run hot, very high B+ and tend to smoke an output tube once in a while. I would suggest separate cathode bias resistors and bypass per channel and beef up the supply a bit. I also prefer the 7189 tube over the EL84. Not for sonic reasons but they have much higher voltage ratings and seem to hold up better in the 35. Overall, a nice sounding little amp. Post some pics when you can.
Regards, KM
I wonder how many people have tried a multiple full range driver in the higher end [Fostex. Lowther, etc]. not line arrays, Using dirvers not less then 6.5" Using 2 or more full range drivers like a MTM enclosure just to get a larger cone area to achieve higher spl's? Using 2 8ohm in parallel not to cause any time delay.
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Hi KM,
Here is the ST-35 built from the Dynakitparts with their BCU (bias control unit) upgrade and upgraded I/O connectors. An excellent kit with excellent support. I had one small question, so I emailed Dynakitparts and received a reply within the hour!
It powered up and is running with no problems. Sounds very good, although I am told that the sound should get even better with a few more hours on it.
The pic of the bottom during assembly is poor because light level was low & my phone doesn’t have a flash. In the second pic, you can see the BCU board in front of the power transformer.
Cheers, Jim
Here is the ST-35 built from the Dynakitparts with their BCU (bias control unit) upgrade and upgraded I/O connectors. An excellent kit with excellent support. I had one small question, so I emailed Dynakitparts and received a reply within the hour!
It powered up and is running with no problems. Sounds very good, although I am told that the sound should get even better with a few more hours on it.
The pic of the bottom during assembly is poor because light level was low & my phone doesn’t have a flash. In the second pic, you can see the BCU board in front of the power transformer.
Cheers, Jim
Attachments
The kit with upgrades plus the tubes adds up to nearly $700 (then add shipping).
I did the assembly with the assistance of Bob, my son-in-law's father (a recently retired TV station engineer). Bob had built many tube kits back in his youth, and was pleased to get involved in another such project. I ended up with a really nice amp for the F120a and nice memories of working with Bob on the project (which are priceless).
Cheers, Jim
I did the assembly with the assistance of Bob, my son-in-law's father (a recently retired TV station engineer). Bob had built many tube kits back in his youth, and was pleased to get involved in another such project. I ended up with a really nice amp for the F120a and nice memories of working with Bob on the project (which are priceless).
Cheers, Jim
Jim,
Very nice indeed... and in the original style chassis as well. I still have a chromed ST35 chassis and new cover sitting about. I'm guessing they implemented an individual bias supply per output tube. Good solution. What output tubes are you running and what is the plate voltage and idle current?
Regards, KM
>>>>What output tubes are you running and what is the plate voltage and idle current?<<<<
The individual bias feature (replacing the cathode bias via a single resistor for all 4 tubes) is Dynakit's BCU upgrade.
OK, here is where my ignorance becomes obvious.
I used the Dynakitparts recommended supplier, Antique Electronic Supply, and chose the ‘upgrade’ tube set: two NOS GE 7247 and matched quad of JJ EL84 (all marked 22/5.4). The assembly manual didn’t ask that you measure the voltages directly on the tubes. All I can tell you is what the manual says is normal (from the diagnostic section, which I didn’t need to use).
For the EL 84: pin 7: 370; pin 9: 375
You now see why I chose a kit rather than do a scratch build.
Cheers, Jim
The individual bias feature (replacing the cathode bias via a single resistor for all 4 tubes) is Dynakit's BCU upgrade.
OK, here is where my ignorance becomes obvious.
I used the Dynakitparts recommended supplier, Antique Electronic Supply, and chose the ‘upgrade’ tube set: two NOS GE 7247 and matched quad of JJ EL84 (all marked 22/5.4). The assembly manual didn’t ask that you measure the voltages directly on the tubes. All I can tell you is what the manual says is normal (from the diagnostic section, which I didn’t need to use).
For the EL 84: pin 7: 370; pin 9: 375
You now see why I chose a kit rather than do a scratch build.
Cheers, Jim
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