has anyone seen the new tube pre? I am very curious on thoughts combining this board with a TA2020. I own a sure amp and there is allot of noise. The idea of incorporating a tube sounds interesting but there does not seem to be much posted here on this combination..
I might even add a miniDSP in one chassis....with a 2.1 plugin.. ?
MKIV Universal Pre-amp Uses all double triode 11 pins valves! 14~30V input! | eBay
I might even add a miniDSP in one chassis....with a 2.1 plugin.. ?
MKIV Universal Pre-amp Uses all double triode 11 pins valves! 14~30V input! | eBay
I don't see any reason to expect it would not perform well, although the supplied Chinese 6N11 may be microphonic which is typical of this tube type.
The tube was originally designed to replace a TV tube but found favour in test equipment (Tektronix scopes, etc). They were popularly re-purposed for low noise phono preamp and headphone amplifier use.
The North American equivalent is 6DJ8 and European is ECC88. For audio use you may want to substitute 6922 (North America) or E88CC (Europe) and British Military CV2493 or European Military E88CC/01 which are all low microphonic versions and typically have gold pins.
Other versions are CV2492 which may or may not be military; as well as the European manufacture they were also made in Yugoslavia and Russia well into the 1980's, possibly longer.
The Amperex Holland/France E188C is a European version of the 7308 (following). Gold pins, high specification.
The 7308 is a US high specification version; matched triode sections, and very tight selection so that any two tubes from the same manufacturer should match very tightly to each other. Gold pins.
All of these tubes in general are quiet with the E188C and 7308 essentially noiseless under almost any circumstances.
Beware of fakes; Chinese knock-offs of Telefunken ECC88, Amperex/Phillips "Bugle Boy" ECC88 are known to exist. The genuine Telefunken labels on the tube itself are somewhat chalky and tend to wipe off; fakes do not wipe off. Similarly, "Bugle Boy" tubes are nicknamed for the cartoon logo on the tube; they were never officially called that by Amperex. The knock-offs sometimes have "Bugle Boy" on the carton itself, a sure sign of a fake. Put another way, "Bugle Boy" should always appear in quotation marks since it's a nickname not a trademark.
I am not a fan of the capacitors used in Arjen's stock boards; you could replace the "audiophiler" marked red caps with your choice. Similarly the volume control is a commodity-spec unit that you may want to consider replacing. Other than that, I don't see any major issues with the setup (although I haven't heard the new tube preamp myself). You should have a basic meter to check trimpot values on the preamp and also DC offset with Arjen's Tripath amps.
An example of an original "Bugle Boy" cartoon logo marked tube:
The tube was originally designed to replace a TV tube but found favour in test equipment (Tektronix scopes, etc). They were popularly re-purposed for low noise phono preamp and headphone amplifier use.
The North American equivalent is 6DJ8 and European is ECC88. For audio use you may want to substitute 6922 (North America) or E88CC (Europe) and British Military CV2493 or European Military E88CC/01 which are all low microphonic versions and typically have gold pins.
Other versions are CV2492 which may or may not be military; as well as the European manufacture they were also made in Yugoslavia and Russia well into the 1980's, possibly longer.
The Amperex Holland/France E188C is a European version of the 7308 (following). Gold pins, high specification.
The 7308 is a US high specification version; matched triode sections, and very tight selection so that any two tubes from the same manufacturer should match very tightly to each other. Gold pins.
All of these tubes in general are quiet with the E188C and 7308 essentially noiseless under almost any circumstances.
Beware of fakes; Chinese knock-offs of Telefunken ECC88, Amperex/Phillips "Bugle Boy" ECC88 are known to exist. The genuine Telefunken labels on the tube itself are somewhat chalky and tend to wipe off; fakes do not wipe off. Similarly, "Bugle Boy" tubes are nicknamed for the cartoon logo on the tube; they were never officially called that by Amperex. The knock-offs sometimes have "Bugle Boy" on the carton itself, a sure sign of a fake. Put another way, "Bugle Boy" should always appear in quotation marks since it's a nickname not a trademark.
I am not a fan of the capacitors used in Arjen's stock boards; you could replace the "audiophiler" marked red caps with your choice. Similarly the volume control is a commodity-spec unit that you may want to consider replacing. Other than that, I don't see any major issues with the setup (although I haven't heard the new tube preamp myself). You should have a basic meter to check trimpot values on the preamp and also DC offset with Arjen's Tripath amps.
An example of an original "Bugle Boy" cartoon logo marked tube:
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hi jonny2bad
have also ordered the tube pre , and also ordered a 9 pin 6H23n-EB from the tubestore with both sections matched so will see how they do, will be interesting to compare with the included tube .
As to the audiophilers well i'm sure it's important to hear all recorded frequencies as they were intended but maybe other than audiophilers can have different signature tones that sound more gracefully musical, especially in the high frequency notes which tend to be exacerbated when using full-range drivers .
reo
have also ordered the tube pre , and also ordered a 9 pin 6H23n-EB from the tubestore with both sections matched so will see how they do, will be interesting to compare with the included tube .
As to the audiophilers well i'm sure it's important to hear all recorded frequencies as they were intended but maybe other than audiophilers can have different signature tones that sound more gracefully musical, especially in the high frequency notes which tend to be exacerbated when using full-range drivers .
reo
do you have any results or perspectives to post? i would be very interested in your feedback?
i piggybacked the pre to my meanwell at 27V that also feeds my 2050's and naturally from there it all went well . there is more volume output (compared to the MK3),i heard white noise from my speakers, either at high or low volume, must be due to noisy tube,kindea resolved this by touching the 2 heatsinks with finger, and later by mistake i pronged the 2 heatsinks together with schrew driver and blew something up or down the line so that was the end of trial test . i might get another one , we shall see later
regards
rol
regards
rol
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Hi there Reo,
That was indeed not a good idea, the heat sink of the Mosfet is not supposed to be grounded.
I can send you a new Mosfet to replace the old one, just undo the nut and bend it forward, then heat it up high and let it fall out.
I might insulate the Mosfet from now on to prevent it from happening.
please drop me a mail at Arjen@helderhifi.com for details.
That was indeed not a good idea, the heat sink of the Mosfet is not supposed to be grounded.
I can send you a new Mosfet to replace the old one, just undo the nut and bend it forward, then heat it up high and let it fall out.
I might insulate the Mosfet from now on to prevent it from happening.
please drop me a mail at Arjen@helderhifi.com for details.
beefier would be better but no harm in trying if the 12V 3.5A is suitable .
Then again he propably mentions it works with the 12V meanwell that are adjustable from 11 to 14V.....14V which seems to be the minimum Voltage required ....but then again only 6.3V is required to adjust the heaters for the included tube and the high voltage trimpot to be adjusted at 60 to 70V
regards
rol
Then again he propably mentions it works with the 12V meanwell that are adjustable from 11 to 14V.....14V which seems to be the minimum Voltage required ....but then again only 6.3V is required to adjust the heaters for the included tube and the high voltage trimpot to be adjusted at 60 to 70V
regards
rol
Hi , I received the following from arjen helder - 1. MKIII Tripath TA2020 PCB with power supply (11-14 volts ADJ @ 3.5 Amps) 2. MKIV Universal Pre-amp . I did not got another power supply for the pre-amp . I understand may be the above power supply will work with the pre-amp too but could I piggyback the pre-amp on the power supply along with the amp or should I get a separate power supply ? If not this power supply, what would be the most appropriate power supply for me to get ? I am not able to go ahead
Thanks Reo . I found the pre-amp pdf also at http://www.data.helderhifi.com/Pre-amp instruction sheet finished prnt .pdf It mentions 1A peak ( cold tube inrush current ) and 400mA Max at 14V 250mA at 30V.
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