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Benjet

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About Benjet

  • Rank
    250+ Post Club

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  • Location
    Brisbane
  • Country
    Australia
  • First Name
    Ben

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  1. Surprised these haven’t sold yet. I would buy them if I hadn’t already just bought a pair from you. Tucking these away as backups of my backup set. I also have the Tungsram branded tubes and these are identical construction and sound.
  2. These are my go to tubes in my headphone amps, they tick all the boxes for me. Highly recommended!!!
  3. I might even have a few more to release and maybe a PDX DAC
  4. If your interested I have a couple of tubes that I’m willing to sell. I’ve pretty much settled on the 5998 tube.
  5. I have a Bottlehead Crack clone and a pair of HD800. My favourite power tube by far is the Tung-Sol 5998. Second favourite were some Rogers 6as7ga. They look pretty much the same as the RCA but seem to have a little more clarity and low down kick.
  6. I’ve had the good fortune to of been able to a had one of these amps on a short term loan. I was wanting to see how this amp sounded on some HD800. I love these cans, but they are extremely sensitive to their source. If you don’t have all your ducks in a row, you’ll certainly know about it. So they are a tough customer and the perfect tool to analyse components. The Gieseler headphone amp didn’t disappoint. What we have here is a very clean, balanced and well textured performance. I’m a bit of a tube man and the addition of a tube preamp threw in a touch of warmth. I’ve owned quite a few solid state amps and this one scores right at the top, doing everything you’ll expect from an amp of this type. As a matter of fact, I much preferred it to the Headamp GSX MK2 I use to own. Highlights of this amp are, *Price to performance is right up there. This unit will give others costing more, a real run for the money. *There is something I really like about the volume control. Smooth and accurate. A joy to use. *Small form factor with plenty of punch. *Typical Gieseler quality. You can tell Clay puts a lot into the design and construction of these. *Balanced and accurate sound presentation. Could of been a touch warmer for my taste, but I’ve caught the tube bug and that’s a common symptom. One other thing I noticed is how well this unit pairs with the Fein II DAC. A truely awesome combo!! If you are in the market for a headphone amp, put this one on your list!
  7. I’ve had the good fortune to hear this amp. An exceptional sounding unit with Mark’s trademark excellent finish. I was using this with my Utopias and really like what it did. Tube rolling yielded even better results. With the ability to take any 12a*7 tube, there is a ocean of possibilities out there. Highly recommended!![emoji106]
  8. Yep certainly is a very powerful, yet great sounding amp. Hook it up to your balanced source and you have a very capable setup. Bargain price considering it will come with $100 worth of tubes
  9. Item: Transformer coupled Headphone amp (on steroids) Location: Brisbane Price: $600 Item Condition: Excellent Reason for selling: After a long search have finally settled on my "perfect" setup Payment Method: Pickup - Cash, Paypal, COD Only Extra Info: It's been many a year since I ventured into the land of headphones and the DIY journey has been filled with wonderful discoveries. It's time to release some of these into the wild for others to enjoy. All these are at below parts cost and have been built and modified and modified again to obtain what I believe is their best sound. This is basically the same amp as the other one advertised, apart for some major modifications. HT power supply has been totally re done. Far superior layout and power filtration (Rubicon and Russian PIO caps). This amp is whisper quite. All components (excluding the toroidal transformer and tube sockets) have been swapped out for better ones. Mundolf interstage caps, Rubicon filter caps, Hammond choke, Alps pot and plently more. Silver solder used throughout. Optimised component layout with internal shielding within case. High and low impedance headphone sockets A lot of time and effort went into this build with exception results. Currently fitted with some Russian tubes and I will supply 2 other sets so the new owner can change if necessary. Really sad to see this one go, but I would prefer it being enjoyed by someone than sitting around being unused. ELECTRICAL DISCLAIMER This product has not been manufactured by a qualified individual or company, therefore contains electrical circuits that do not necessarily comply with Australian Standards. I understand that as the seller, I may be liable to repercussions in the event of equipment failure. By advertising and selling this product, as the seller I also agree that I am solely liable, and the publisher of this website takes no responsibility for any injury or death resulting from, whether directly or indirectly, any accident that may happen as a result of the failure of the product being sold. If in doubt, seek the services of a qualified electrician to inspect the product to ensure it is safe for use
  10. Item: Transformer coupled Headphone amp Location: Brisbane Price: $350 Item Condition: Very Good Reason for selling: After a long search have finally settled on my "perfect" setup Payment Method: Pickup - Cash, Paypal, COD Only Extra Info: It's been many a year since I ventured into the land of headphones and the DIY journey has been filled with wonderful discoveries. It's time to release some of these into the wild for others to enjoy. All these are at below parts cost and have been built and modified and modified again to obtain what I believe is their best sound. This is an interesting amp of which I bought from a fellow SNA member. It used 6j6 tubes configured in push pull driving a output transformer. I always had my doubts about output transformers and this amp certainly changed my views. For people who attended my latest "Brisbane headphone" GTG, this was the amp that was powering my Utopia with great effect. Currently fitted with some real nice Amperex tubes. I have plenty of different other tubes and if bought locally, I will work with the buyer to find a set that suits them perfectly. ELECTRICAL DISCLAIMER This product has not been manufactured by a qualified individual or company, therefore contains electrical circuits that do not necessarily comply with Australian Standards. I understand that as the seller, I may be liable to repercussions in the event of equipment failure. By advertising and selling this product, as the seller I also agree that I am solely liable, and the publisher of this website takes no responsibility for any injury or death resulting from, whether directly or indirectly, any accident that may happen as a result of the failure of the product being sold. If in doubt, seek the services of a qualified electrician to inspect the product to ensure it is safe for use.
  11. Item: M3 AMB Labs Headphone amp and 24v supply Location: Brisbane Price: $450 Item Condition: Very good Reason for selling: After a long search have finally settled on my "perfect" setup Payment Method: Pickup - Cash, Paypal, COD Only Extra Info: It's been many a year since I ventured into the land of headphones and the DIY journey has been filled with wonderful discoveries. It's time to release some of these into the wild for others to enjoy. All these are at below parts cost and have been built and modified and modified again to obtain what I believe is their best sound. AMB Labs M3. This is where my DIY journey began. Fitted with some genuine OPA627AP opamp (@ over $45 each) which can be "rolled" to give a different sound signature. All the other component are of the highest quality, this was a no holes barred build. This amps has served me well through several sets of headphones beginning with some HE-500 of which it could drive the pants off. Here are some of it's technical highlights. And more can be found here https://www.amb.org/audio/mmm/. Amp comes with a ultra low noise 24v power supply. 3-channel active ground topology In addition to the left and right channels, in this amplifier the "ground" wire of the headphone is actively driven by a third channel of the same topology. The ground channel amplifier sources or sinks the return current from the transducers, which would otherwise have been dumped into signal ground or power supply ground. This shifts responsibility for the high current reactive load of the headphones from signal ground to the tightly regulated power supply rails, thus removing the primary source of signal ground contamination. The headphone transducer "sees" symmetrical output buffers with equal impedance and transfer characteristics on both sides, rather than an output buffer on one side and a capacitor bank of the power supply ground on the other. High performance opamp voltage gain stage and high current discrete MOSFET output stage A high performance IC opamp is used for voltage gain duty in the M³ amplifier, while the discrete power MOSFET output stage provides the current gain to drive the headphones. This separation of functions isolates the headphone load from the opamp and allows it to operate without strain. Both stages operate in class A for unparalleled linearity. The MOSFET output stage has enough output power capability to drive efficient speakers to reasonable volumes. Capacitance multiplier for opamp power The power supply to the opamps is further isolated and stabilized with a complementary capacitance multiplier. A capacitor is kept charged by two JFET current sources at each side, whose capacitance is then multiplied by the DC current gain of the complementary pass transistors to provide very low noise, low impedance DC rails to the opamps, unperturbed by the MOSFET supply rails. Precision virtual ground reference Rather than using a conventional split power supply with positive, ground and negative outputs, the M³ amplifier uses a single supply and internally synthesizes a virtual signal ground by using the TLE2426 precision rail splitter chip. This simplifies the power supply requirement, yet provide the advantage of a dual-tracking split supply without associated complexity. The result is improved common-mode rejection ratio (CMRR). Adjustable JFET cascode current source The opamp for each channel is biased to operate in class A by a pair of discrete cascoded JFETs. This prevents the opamp's output transistors from ever cutting off, eliminating crossover distortion. The amount of current flowing through the JFET cascode is adjustable via a trimpot. Adjustable MOSFET bias The MOSFET bias is controlled by a VBE multiplier transistor and the quiescent current is adjustable via a trimpot to suit individual needs. Fully direct-coupled There are no signal-degrading coupling capacitors at the input, output or negative feedback loop. This is a true DC amplifier. The precision FET input opamps keep the DC offset very low, but care must be taken to ensure that the input source does not have DC offset at its output. No input or output protection The rugged and stable MOSFETs allows the simplest of output circuitry, providing maximum sonic transparency. Optional bass boost feature At the builder's option, a bass boost feature (either via an on/off switch or a continuously variable adjustment) can be installed to compensate for poor recordings or headphones without sufficient bass response. Board-mounted premium potentiometers The circuit board is designed to accommodate ALPS RK27 "blue velvet" or Noble AP25Y audio-grade dual-gang potentiometers for excellent inter-channel tracking. They are directly mounted onboard for the shortest signal paths to minimize crosstalk and interference. Ground plane Low impedance ground plane over low level signal areas provides shielding against interference, reduces crosstalk, and allows optimized component arrangement on the board. High-current, superimposed power buses for MOSFET power Wide "power plane" traces provide a low impedance path of DC power to the MOSFETs, with reservoir capacitors located immediately adjacent to the MOSFET banks. ELECTRICAL DISCLAIMER This product has not been manufactured by a qualified individual or company, therefore contains electrical circuits that do not necessarily comply with Australian Standards. I understand that as the seller, I may be liable to repercussions in the event of equipment failure. By advertising and selling this product, as the seller I also agree that I am solely liable, and the publisher of this website takes no responsibility for any injury or death resulting from, whether directly or indirectly, any accident that may happen as a result of the failure of the product being sold. If in doubt, seek the services of a qualified electrician to inspect the product to ensure it is safe for use.
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