Hi. I had a conversation with a member of your staff earlier this week about buying a black AT1000 to match my AT3500 CD player.
During the conversation we got into the subject of 'tube rolling" in the AT3500. I mentioned I think that a friend was going to lend me a NOS Mullard gold pin E88CC to try in the AT, which had a factory fitted Philips JAN tube when it was supplied. I may be wrong, but I think I agreed to let you know how it worked out.
In short, I'm quite impressed with the Mullard. It is I think different to the 6922 - less 'glassy' on some not so well mastered CD's, quite 'bassy' - its as if I had a subwoofer - which I don't. That is not to say that the bass is all loose and uncontrolled. It isn't. It is also interesting that the sound produced using the upsampling button is very different with the Mullard. with the Philips tube the upsampled sound was quite 'ethereal'. I didn't like it at all, and never used it. With the Mullard, using upsampling changes the sound stage, but it doesn't lose body.
I'm running the AT into a Quad 24 Pre, Quad II/40 power amps and a pair of Martin Logan speakers.
Anyway, I'd recommend that if people want to try different tubes in the AT that they put a Mullard on their list. They may or may not like the sound, but at least they will get their money back if they decide to sell the thing on, as they are pretty hard to get hold of.
One final thing. The Mullard I'm listening to tested out at the lower end of the normal range for anode current, so it is probably past its best. I would like to hear a good one.
Anyway. Back to more listening. I'm glad I bought the AT. I had (well I still have) a Linn Ikemi, and TBH I much prefer the AT.
Cheers, Iain Lockerbie
PS you did say that there were some upgrades in the pipeline for the AT3500. Please let me know when they will be available.
We can now confirm that yes, there is a new AT3500plus product available, and it will be reviewed in the May issue of Hi-Fi World magazine; and here is some background and a description of the two new updates for the AT2000 amplifier and AT3500 CD player, now available:
Both the AT2000 and AT3500 represent good value designs in their standard forms, offering a high level of musical satisfaction. Since the AT3500 CD player was launched, we have known and have been suggesting that there are NOS (new old stock) valves available, such as the Philips JAN 6922 that offer a significant improvement to the ‘standard’ Electro-Harmonix valve supplied.
During the last year, we have also been experimenting with a considerable number of other component upgrades, as part of our continuing development programme for future product.
It became clear to us that some of the more obvious ‘improvements’, whilst perhaps offering some small additional insight into the music, were not very good value for money – and these included exchanging power supply capacitors with acknowledged ‘better’ audio types and changing the filter I.C.’s on the DAC with higher cost audiophile components. Put together, they do offer an improvement, but double the price of the machine.
It was the ‘smaller’ changes we made that really offered a considerable difference, and at a reasonable cost. We therefore decided that whilst we were not going to become rich offering these ‘good value’ upgrades, they offer such a good value relative to the standard product price, that this would be a popular option for many customers.
These we call the plus versions, and they come with a certificate showing that they are an Astin Trew authorized upgrade. The plus modifications are offered on new machines or as an upgrade path for both the AT2000 and AT3500 after purchase.
We replace a number of the critical capacitors in the signal path with Auri-Cap polypropylene types, as already used in the standard AT3500. All line level signal cable is replaced (and hard wired) between input and PCB’s with super pure single crystal cable. Valve dampers are fitted.
All line level signal cable is replaced (and hard wired) between input and PCB’s with super pure single crystal cable. Eleven critical I.C.’s on the DAC board are damped with custom heat sinks, bonded into place with thermally conductive adhesive. Philips JAN 6922 valve is fitted.
Both products sound significantly improved in many, if not all areas of musical reproduction. These are some of the comments we have had fed back to us from dealers and reviewers:
* there is a deeper ‘blackness’ to the background
* bass is tighter and goes much lower
* instruments are much better placed within the sound stage
* there is more 'in-focus' detail
* there is better ‘timing’ of the music
* the overall musicality of the products is not changed.
Michael Osborn,, Dir. April 2009
Both plus modifications add just over a couple of hundred pounds to the product price, but do offer a substantial improvement and make a super upgrade to the standard products, if you want the very best musical enjoyment from these two products.