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Found 12 results

  1. Great vintage preamp. Class A with excellent adjustable phono stage. In great condition. Bought as part of the set but using my home cinema as pre due to room issues and eq. Comes with 110/220V selectable source. Quite old but very good condition. Want £275 + delivery. Post anywhere for cost - guess around £15 uk, £25 EU £40 elsewhere but ask so I can check.
  2. Bryston BP-26 with MPS-2 in silver for sale. Very good used condition with only few minor marks/scratches. Comes in original pacakging (boxes are quite tattty) with genuine metal remote and PSU cable. It came back from Bryston UK yesterday where it had performance check and service. £1895 collected from Woolwich Arsenal or buyer can arrange postage. Selling as have 5 preamps in the house. Would consider swap to interesting power amp (solid state or valve) also could take some decent rca interconnects as PX.
  3. Bought this DIY preamp from Myles on the wam some time ago as always wanted to try one. One of the biggest bargains in audio imho. Remote controlled, with battery. £200 plus postage.
  4. For sale is my Croft 25 Line Preamplifier. Bought from Audio Flair, owned from new and in excellent condition. The volume pots I custom requested to use the older solid variety as I prefer the aesthetics. Additionally I had Adrian Parsons of Audio Flair reduce the gain the gain to zero, making it more appropriate with the Quad 909 I used it with. Also had great results upstream of Event Opals. The Croft has the original JJ valve however I used another one so this one has had little use. Looking for £420. Kent https://flic.kr/p/2kvBVZ9 https://flic.kr/p/2kvyiN9 https://flic.kr/p/2kvCsNu https://flic.kr/p/2kvyiLA https://flic.kr/p/2kvBWst
  5. icOn 4 (AVC) Passive Preamplifier Review by George Sallit I am fascinated by passive preamplifiers (Control Units?) and have been for a few years. One of the advantages of digital analogue convertors DACs (the only one?) is they have a healthy output of 2V. With power amplifiers giving full output from an input of 0.7-1.5V that in effect means the need for preamplifiers has gone and all that is needed is an attenuator and a switch for the different inputs. No amplification is necessary. That opens the way for a very simple preamplifier as all it has to do is have a variable attenuator. The simplest of these passive control units can be just a variable potentiometer in a box, the infamous ‘pot in a box’. You can either make a simple one yourself or for those, with my awful soldering skills, there are hundreds of commercial ones available. One of the first was the Creek passive preamplifier with a decent pot (Blue Alps) with a motor drive. Add the ability to switch between the two inputs using a small electronic circuit and you have a cracking ‘pot in a box’ that had a remote control. I bought one and it could not be simpler. It would be pointless measuring it as it is in effect perfect. And listening to it provided good transparency and clarity. There was no distortion added. It sounded excellent and only cost a few hundred £s and was capable of embarrassing more expensive active preamplifiers. It should have sounded perfect. But……it did roll-off some of the high frequencies and reduced the dynamic impact. Nevertheless, an excellent controller. Well if a pot, which has a carbon track and a sweeper, was not quite there how about 2 resistors? A variant on the passive theme was to have a series of resistors that changed the values of attenuation. Enter the stepped attenuator. This neat device would have a set of volume levels given by a series of resistors but with only two connected at one time. One of the better examples was the Khozmo stepped attenuator. My version was well made and had a complex looking volume controller with 48 resistors soldered per channel. As you turned the volume control different resistors were switched in. That must have been a tedious job and a half to solder all those resistors. The Khozmo sounded superb and to be honest was much better than the cruder Alps ‘pot in a box’. But it did not have remote control?? A quick word with the maker, Arek Kallas, showed he made a much more sophisticated version with 64 steps, lots of inputs, outputs and it was a true balanced volume control. Yes, there were 4 of these resistor marvels for both the + and - XLR connections and of course you need that for both channels. I ordered my version with high-quality Takman Rex resistors and this sounded ideal with only a hint of a loss of top-end sparkle and a tiny reduction in dynamics. Impedance issues? And of course, it came with full remote control! However, there are another 2 ways to control the signals but using transformers. I bought a great example of a transformer control unit. The Music First uses a high-quality transformer that takes in the 2V signal from the DAC and then induces in the secondary set of windings the outputs. Using a transformer meant there were fewer issues with impedance matching that afflicts resistor-based passives. And maybe improvements in sound quality? Yes, you bet. These small boxes worked their magic and gave resistor-based clarity and transparency without the negative impact on the dynamics. They were pseudo-balanced as well. Transformer Volume Controllers are an exceptional example of clarity and transparency and they have big dynamics. I was more than happy with the MFA as it worked its magic with all the amplifiers I had to hand. Well, all bar one and as luck would have it, it was my favourite amplifier. But I could live with it. Here was a preamplifier with excellent sound quality, well above that provided by similar priced active preamplifiers. But it did not have remote control unless you were prepared to pay another 50% of the price. All was rosy (ish). And then. The final variant and the word from ears I trust, ‘You have to try passives that use autoformers’. OK but all I could find was the Townshend Allegri. In autoformers, there is only one coil of wire that does the lot. And instead of needing about 2kms of wire for a TVC, the autoformers use 200 metres of wire. So, I bought one. And I was home and dry. It worked a treat and had nearly everything I needed. The sound quality was exceptional and the equivalent or better than multi-thousand £ active devices. And others reported they were the best preamplifiers around. One reviewer used his Allegri so much he wore out the volume control. Quietly people were saying they were better than £20K preamplifiers. And I could believe them. But (what a greedy devil I am)… no remote control and the input RCAs were too close together for my favourite cables with their chunky connectors. And now I am onto what appears to be the best of the best. An autoformer using a transformer made by one of the world’s best makers of them, David Slagle. The inputs were all electronically switched (no mechnicals to wear out), it had a remote volume control, remote balance control and a few other electronic goodies. The metal box it comes in is a solid affair and looks kinda cute. The remote is an Apple and it provides all you could need. This Wonder pre is the icOn 4 preamplifier made by Life Changer Audio run by Pal Nagy …who migrated to the UK from his native Hungary. He had worked in the electronics industry and wanted to bring high-quality autoformer preamplifiers into the 21st Century. He uses electronic switches with lifetimes measured in hundreds of years and no not those that go ‘click, click, click’…but ones that are silent. This preamplifier was easy enough to use and worked faultlessly from day one. It has 40 volume steps nearly 2x more than other passives. He uses a ‘dreaded’ switch mode power supply. And I have to admit I never heard a difference when I used it. Excellent isolation. So, what does It sound like? In a word, superb. It has all the clarity and transparency I hear from good passives but with all the dynamics and sparkle from the best actives. I listened to it play my reference test music and the clarity and drive in the bass was fast and powerful with no additional ‘extra’ weight. As you might expect it added nothing. The James Blake track Limit to Your Love was not heavy or leaden and it was easy to hear the differences in the tones in the bass. And the powerful bass from Snarky Puppy’s, Culcha Vulcha, Tarova was just right. It was their first studio recording in 8 years when it was issued in 2016. The music goes off at a cracking pace with all 17 members letting go, led by the organ, Rhodes piano, with a thrumming bass, swinging violin, and blazing horns that remind me of Muscle Shoals and the drive of this song relies on the balance between the bass and the drums. The track can sound confused when all that lot let rip but not with the IcOn 04. Voices were clear and it was possible to hear the small details that allow you to hear the emotion the singer is communicating. Laughing Lenny’s (Leonard Cohen), You Want it Darker is a really sad song, which is communicated with impact, more so knowing that his time on earth was limited. It was possible to hear his singing skills without turning it into an audio autopsy. His vocals were not the finest but nevertheless very poignant. And you want sparkle and air? The Icon 04 had it in spades and allowed me to hear the space that great recordings were made in and hear the differences, clearly, between a large church and a huge cathedral. Misa Croila by Mercedes Sosa is recorded with a completely different microphone set up and environment to that of the Jose Carreras’s version. One is more closely miked and the other recorded from the middle of the church. But when listening to Rock and Roll by Led Zeppelin the introduction features Bonzo really rattling the cymbals. But it is not hapless bashing but a way of creating a wall of cymbal sounds with subtle inflexions to increase the tension as Robert Plant runs with the song. It is fast-paced rock and roll and sounds it. But the big question. That is all well and good but how does it compare to the Townshend Allegri? And confession time here….Errrr…..I could not hear a difference between the IcOn 4 and the Allegri. I listened and listened and thought I could hear a difference but no when I reinstated the original preamplifier the differences disappeared. Oh dear, time to hand in my reviewer’s badge? In discussions with Martin Colloms at Bristol, he said he needed his £100K system to hear a difference and a small change in the quality of a cable would make the differences disappear. Good, I am not going mad (well I might be!). So, I am going to call it a sound quality draw. So where does that leave things? Sound quality wise these two autoformer passive preamplifiers are the same/similar to me. The IcOn 4 however, is more flexible, it can accommodate the big RCA connectors used on Audionote silver cables. It has remote control and balance control. Oh, and is nearly £1K cheaper. The IcOn 4 is a great sounding preamplifier, it is modern with switches that will last a lifetime, it has remote control operation and all for the princely price of £1600. It sounds better than a lot/most active preamplifiers, which makes it a barg**** in my books. System used Melco N100 + Plixir balanced PSU dCS Bridge streamer Audionote DAC 4.1X, Chord Qutest Pass Labs XP22 Pass Labs XA 30.8, Transcription Audio 211 amplifier, Nord N500 amplifier, ARC Ref 110 Audionote E Silver Signature speakers Cut Loose silver ribbon cables. Specifications unbalanced inputs and outputs, 4+1 or 3+2 autoformer volume control with 40 volume position smooth control (1.5 dB steps) even at the lowest volumes broad volume range: from -54 dB to +3 dB balance: +/- 7.5 dB distortion: less than 0.01% channel mismatch: less than 0.1 dB instant mute full remote control with Apple Remote 7 digit LED display for volume, balance and input 2 display brightness and night mode AV bypass function optionally non linear switching algorithm executed by hermetically sealed miniature reed relays or Vishay FET switches lifetime of reed relays: 1 billion switches (approx. 500 years) power: 5V/200 mA size: HxWxL 70mmx120mmx260mm weight: 2 kg warranty: 2 years https://www.passivepreamp.com/ UPDATE The owner has contacted me and told me has updated the icOn 4 to the new icOn4 PRO which has more flexibility and features with many more volums steps. A Broader range of inputs have been added and a new fully balanced model is available. Of course they all still use the excellent David Slagle AVC transformers. icOn 4 4PRO comparison.pdf
  6. With the Reviews section in abeyance I thought I would still go ahead and give you my thoughts on the little Khozmo passive preamplifier: It was twenty years ago that Sgt Pepper taught the band to play…… Well it was actually 34 years ago (yes 34 years!!) that CD hit the (audio) world. It brought a whole range of plusses and minuses that have been worked on for the last 34 years. Real progress has been made. It took some time but it has become the mainstay of music delivery even though now it is being overtaken by streaming. One of the possible plusses involves the audio bit of the DAC. Nearly all DACs use opamps or discrete components that provide an output of 2V. This has become an unofficial standard, although the XLR variant gives 4V. With power amplifiers requiring about 1V for full output this allows a change in the role of the preamplifier. If the output of CD/DACs was 2V and the power amplifier required 1V then all that was needed was to attenuate the output signal down to 1V or less. This brought about the possibility of using very simple single/two component (preamplifier with no amplification) attenuators. The birth of the passive preamplifier/attenuator. Making the thing less hair shirt some added source switching and heaven forbid……..remote control. Now this brought great promise. There would only be 1/2 components between the DAC and the power amp. How could it get any better? Stunning sound quality, cheap costs and every one would be smiling, bar preamp manufacturers. But it did not work out that way. Everyone and their dog built a pot in a box, one set of input and output connectors and stunning sound flowed………er not quite………or not always. For me I saw this happening and bought a CD player with the volume control built into the CD player itself. It had a digital volume controller. How could anything go wrong? It did and I preferred my active preamplifier. In fact, the in-built volume controller sounded terrible. Why? Well despite the great promise, the volume controller worked by ‘decimating’ the signal. It reduced the volume by chopping off some bits. Awful. They have got better now. OK along comes Creek who actually put together what I regard as a cracking item, the OBH 22 preamplifier. It has three inputs and two outputs. A source selector, a volume control and used a high quality Blue Alps pot, all with a natty remote control. With my ARC valves it required a really brilliant preamp to sound better. All it would do that was negative was to lose some bass impact and soften the overall dynamics. But it was incredibly natural, ultra-detailed and very easy to listen to even on rock music. However, occasionally it just did not work with some equipment and it sounded soft and quite mushy. Not often but it required care in matching impedances. Using long interconnects between the attenuator and the power amp could lead to problems. But taking care to keep interconnects short (1m) then all was OK. However, it is no more as Creek do not make them anymore. A pity. Recently there has been a huge interest in passive attenuators and that has produced many variations on a theme. There are many simple pots in a box. There are more sophisticated step attenuators where individual resistors are soldered onto the volume controllers and instead of the volume being continuously variable it is attenuated in steps. There are variations of even this type including shunt attenuators where one resistor is always in circuit and another is used to provide the steps of the volume control. There are Light Dependent Resistors where a change in the voltage of a small light source affects the LDR, it changes its resistance and it is connected to the output volume. And of course there are transformers that attenuate the signal either through Transformer Volume Controllers (TVC) or auto-formers. As you may expect all have their advocates. I am looking at the Khozmo Passive Preamplifier (Attenuator), which is a stepped shunt attenuator. This is a company I have not come across before. They are based in Poland and you buy direct from them via the internet. This is something that is becoming more common and promises to give good products at a reasonable price as the mark-ups from the distributer/shop are not added into the price. However, you have to buy blind and rely on any money back promises and reviews like this one and people’s experiences. It is possible to buy this shunt attenuator with different quality resistors for both the shunt resistor and the switched-in resistors. Khozmo sells the standard attenuator with Caddock and Vishay resistors with upgrades possible to the Takman Rex and Vishay Z foil resistors. They are sold with either 10/20/50/100/200Kohm input impedance and in my case the 10K variant was recommended as I was using it with the Nord Class D power amplifier. The attenuator goes from -60 to 0dB in 48 steps (2dB increments from 1-11 and 1dB from 12-48) with make-before-break switches, hard-gold contacts, ±0.1dB channel matching, just two resistors in the signal path at any given setting, CNC-machined PA11 aluminium bodies and a precision ball-bearing support. Everything is hard wired with solid silver core wire. Because I listen slightly off centre I asked for the dual mono version which is slightly less convenient than using a stereo version but you do get control over the balance. My attenuator had three input and two output with phono connections (which led to an odd problem later). The box is very well made. It is quite weighty and looks the part with wooden cheeks and the controls have a nice solid feel. Overall, including the attenuators, it is well-built and it is hand made to boot. If you buy the stereo version, it can be remotely controlled at extra cost. The really good news is the basic model costs $300. My model cost $400 which with postage made a landed priced of £320. So how did it sound? Well I wanted to use it with my Auralic/Aries+Audionote DAC2.1x front end, the Nord Class D power amp and Audionote E/HE speakers. I therefore had an issue with the power amp needing XLRs and the Khozmo I bought using phonos. Maybe I should have got the XLR variant. Anyway in goes two amorphous make XLR/Phono adaptors and I get a sound out that it is very good. But I can surely do better with a Cardas XLR adaptor? I buy a pair and things did not work out. So eventually I go for the Neutrik XLR/phono adaptor and all is now well. Well enough prevarication how did it damn well sound? Well as you may expect from having just a couple of resistors in the circuit extremely neutral and natural. The 3D soundstage is big and it has great width and depth and dare I say it height. It also shows up a lot of studio recordings as being very dry and artificial with their limited soundstages. I used the old demo favourite of Misa Criolla featuring Mercedes Sosa and you can hear the large acoustic it was recorded in and the echo fading away. As you may expect there is no noise coming from the speakers with a passive attenuator and an extremely low noise power amplifier. You can therefore easily hear the echo from the acoustic as it gently fades down to zero with no cut-off. The bass was big and powerful with no overhang. The bass tonality was very good. It was possible to easily hear the different types of bass and the tricks done in studios. Onto something musically different, Dystopian Overture from the new Dream Theater album in 24/96. The tricks used in this studio creation were easy to hear and very clear. In the middle of this track there is ‘kitchen sink’ moment where all sort of instruments are added and taken out of the mix. Their different added echo and layering is easy to hear. After listening to that section of music it feels like you have been on an audio assault course. You have been overwhelmed and given a feeling of being taken over which may have been what the band wanted to paint for this desolate future. Other preamps can become confused by this passage making it messy and less unnerving. Of course it is not perfect. Despite using high quality resistors the dynamics are not as sharp as those from active preamps and the high frequencies do not have the air of transformers or active preamps. Active preamps still have that huge drive and attack and this resistor based attenuator is a little softer. But for me it is more relaxed and easier to hear for longer periods of time. Maybe not as showy. If you are concerned about whether everything will work and need to check the impedances Arek is great with advice and always responded to my e-mails very quickly and allows return of the product if it does not work out for you, within a reasonable time period. In conclusion given that some of the other preamplifiers I used (Nuforce P9 active preamplifier, Audionote M6, Creek OBH 22) were far more expensive than the little Khozmo and it was not embarrassed or shown to be deficient apart from a few minor areas makes it a bit of a bargain. It is highly recommended and you can get any variant you want. So let me introduce to you The one and only……….Khozmo…..
  7. Hi, Looking to buy good preamp. Solid state or valve, ideally with remote and balanced ins/outs. Will pair with Vitus Audio mono blocks.
  8. JE Audio VL 10.1 Preamplifier - £1345, RRP - £4499 **SOLD** 1 owner from new, in excellent condition. This preamplifier received fantastic reviews. Read the Soundstage HiFi Reviewer Choice award review here Read the 6moons review here Read the Positive Feedback review here UK Retail Price here See the listing on our website here 12 month warranty provided. Elite Audio are part of Audio Emotion, so you can buy with confidence Please call us on 0203 397 1119, PM or email us at info@eliteaudiouk.com for more information.
  9. Pro-ject Pre Box RS in silver, balanced valve output stage, remote control. (nb. the RCA outputs are fixed, it should come with XLR-RCA cables but the previous owner did not include them, I will throw in custom made by Mark Grant 50cm Van Damme Green 110 Ohm Neutrik XLR to Neutrik Profi-phono RCA if your power amp has RCA inputs). Pro-ject Power Box RS Uni 4-way in black, linear power supply that can feed 4 Pro-ject RS components. The previous owner also did not include the basic SMPS for the preamp, so these units need to be sold/bought together. Both in excellent condition. £550 delivered in the UK. Images won't appear for some reason, here are links: http://imgur.com/a/0kDNG http://imgur.com/a/hXF9G
  10. Naim Nac 122x pre amp. £375. Full working order and stunning condition with original box/packing/manual and of course remote control which is hardly used. Cosmetically almost perfect, the only blemish is a tiny scratch near the volume control as shown in pics, which I only noticed when taking pictures for this ad! Collection from Brighton or can send at buyers cost.
  11. Exposure XXI preamp in black with remote control, original box and XLR leads. In really superb condition. £360 delivered in the UK. Poor picture from phone but there it is in the rack: https://drive.google.com/file/d/0ByAlo05YhV1QVXpDTTBsTHdyaXc/view?usp=sharing Thanks
  12. In Excellent condition ,perfectly balanced L,R channels and matched NOS tubes (SOVTEK) with very low hours,all the electrolytic capacitors replaced professionally recently with caps from Panasonic and Nichicon ordered from Mouser. Also New Volume Pot fitted exactly the same as the original. In Excellent working order,everything tested and it work as it should. All In original condition without any kind of mods. A rare opportunity for anyone who wants a really good Reference Tube Preamp, the Melos 333 pre and the Melos monoblocks used from Grado and Mobile Fidelity among others in their listening studios. PRICE:£1600 + shipping Thanks Nick
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