In-car Tube amplifiers: good idea?

[Chris_D]

Being the owner of a few tube headphone amps and appreciating the resulting improvements/change characteristics that can be achieved, I'm now thinking about upgrading the existing amp in the zed to a tube amp.
Thinking about this one from that there America:

http://milbert.com/bam235ab

Plenty of space enough in the boot for this one maybe.
Anyone here done an install in the boot with a tube amp? Interested to know of any experiences. Microphonics and premature failure (due to increased vibration environment) in the tubes would be my biggest concern.

 

[vester86]

Not a good idea for 2 reasons:

1) heat, as the boot it not so well ventilated and a tube amp gets pretty hot in my experience
2) tube & vibrations is a very bad combination.

 

[Chris_D]

Not a good idea for 2 reasons:

1) heat, as the boot it not so well ventilated and a tube amp gets pretty hot in my experience
2) tube & vibrations is a very bad combination.

Agreed, totally. My concerns also as initially stated. However, on the website theyre making some bold claims including:
"Every imaginable problem solved long ago.
Not microphonic. Runs cool. Lasts. Sounds great."

Quite tempted to take a punt.
Keen to hear if anyone here has done a tube install as part of a system....

 

[Nictrix]

Wheres James Bond when you need him, this would have been right up his street.

 

[SeanConnor]

The fact that they claim the tubes to be non-microphonic is really not that impressive. The gate spacing should be quite rigid It's the heater coils that will take a hammering. I'd be interested to hear from people who have been running these for a period of time. Of course in the olden days they fitted vacuum tube set to aircraft. They were known to vibrate a bit

 

[faz_b]

Not the greatest idea on a budget level for the reasons stated above, but it can be done and in fact when it is, its often in high end kit. Panasonic had this head unit out with very little in terms of reliability issues and it was highly regarded in SQ circles for a number of years - but the purchase price was circa £1000 I seem to recall. Obviously no good for the z4 though and the tube took a little while to warm up.



When it comes to amps, if I were adamant on tube amps, then I'd be looking at dedicated car audio brands who have a reputation for solid kit. Which the Milbert fits. Its an incredibly rare piece of kit to find...Although I hope you realise it has a price to match... at last check a couple of years ago it was over $4000USD!!

Butler Audio also produced a range of tube amplifiers a number of years ago which were pretty good and much cheaper than the Milbert, but they are also difficult to source I believe and I seem to recall they were a hybrid design using the tubes for pre-amp stage only. They did have a decent reputation though. If you find one of these on the second hand market they tend to be worth £200-£300 or so.

If it were me looking at a in car tube amp, I would be looking at one specific model (which is again very rare) a Tru Technology C-7.2AT. Newer design than the Milbert, has been used in multiple reputable high end installs and by god it is a thing of beauty...

Just looks like a slab of "I WANT THAT!" :wub: :wub: :wub: Market rate on these is anything between £500-£1000 depending on condition and usage. I have heard a couple of these run off a pre-amp only denon head unit with a Dynaudio front end and phase linear flat piston subwoofer in (of all cars...) an old rover! Sounded utterly divine

In general the consensus is correct, tubes in car are not the most reliable, but for the few manufacturers that have pulled it off and are high end, the results can be bloody exceptional. All these leave the generic Rockford Fosgate/JBL/JL Audio type gear WAY behind, but most of them command a premium price, are discontinued and/or are bloody hard to find.

That said, for the sort of money you would pay for them, you could build a pretty incredible audio system. Unless you are a serious tube amp fan, financially its not particularly worth it, but the scare stories in terms of heat and reliability at the top end of the market don't really apply at all.

My personal holy grail in car audio wouldnt be a tube amp though. I would want a classic limited edition 7 channel SoudStream Davinci. absolutely stunning piece of kit. They NEVER come up for sale and when they do still fetch in excess of £1500. :? :wub: :wub:

I should probably state that I was in the car audio industry for a number of years and followed it as a personal passion for ten years if it means anything btw!

EDIT: Important point, no point in just upgrading the amp. The stock z speakers are full on pants - better to look into a amp AND speaker upgrade if you want to get the best of out it.

 

[Chris_D]

Wow! Thanks for that comprehensive post faz! And yes, i remember you mentioned u were in the industry in my tape player thread.

The milbert is def going to be out of my price range, and i'm looking to achieve something on a budget.
The Littledot Mk3, Musical Fidelity X-can and my two KT-88 headphone tube amps have transformed the way i listen to music now and i'm looking to emulate the tube effect in the zed, preferably using some Mullard tubes. As you probably know those amps arent considered top end kit but for me they do the business in transforming the sound.

I remember seeing an in-car tube amp made in korea some years ago using tubes in the pre stage. Was a great looking thing and as I'm really only interested in the sound signature of the tubes i dont mind solid state amp stage.
Any ideas what the name of that thing is/was as i just cant remember?

Edit: that davinci thing looks insanely cool!

 

[faz_b]

No worries

On a budget Im honestly not sure about tube amps in car and unfortunately I dont know of any korean car audio brands off the to of my head that I would trust or have tubes either!

I seem to recall reading a thread somewhere about some people who had actually built their own DIY tube amps on a car audio forum somewhere a number of years ago with varying levels of success (some surprisingly robust and well thought out!) I'll see if i can find the link.

The other option you might want to consider is going for pure class A/B amps if you can be pulled away from the tube fetish! Whilst not fuzzy with a lovable crackle, they do tend to sound warm (generally of course) You will get MUCH more of an impact from changing your speakers than an amp though.

 

[faz_b]

The davinci was indeed a crazy amp! Came with a balanced line level converter that sat at the processor end, which was then re-converted at the amplifier to ensure it didnt pick up any distortion on a regular RCA cable travelling down the car. The spec on this thing was absolutely insane. When you consider that it was made for only a few months, hand built and is 20 years old but still appeals... well.. sort of says it all!

Removing the soundstream logo from the top panel gave access to the full features of it - crossovers, eq, subsonic filters etc. few more pics:

 

[wspohn]

While I agree with all that was said about the challenges an automotive environment poses for tube gear, I think that the real question is what benefit you could expect in a small car. I think the answer is probably going to be 'not much'.

I've been involved with some high end car systems and had long ago concluded that unless you have a vehicle with significant internal volume it is a thankless task. For that reason I generally leave my car systems alone, aside from swapping out the odd driver for something better. I use the car to drive home to my serious systems so am not overly critical of how the sound in the car might be on the way.

PS - David Berning, a highly regarded designer, was involved with the Milbert brand, which says something for it.

 

[Chris_D]

The davinci is pure car audio porn!
In retrospect, it's probably better to stick with a portable solution then, and have it sat on a cushion on the passenger seat.
Currently using an opus1 DAP to play 24bit FLAC's and DSD's, routed through an Alo Audio Continental:


Also have a Fiio E17 when the Alo is charging but that's purely to boost the line signal.

Agree with both of you, faz and wspohn that it may be a thankless task to try and emulate a tube signature in-car as the difference in listening between the Alo/Fiio/Opus is marginal except in only the quietest of driving environments - motorway at about 65mph.

Might just shelve the idea in favour of focusing on quality speaker/ ss amp upgrade for existing sources.
Thanks for the input!

 

[Chris_D]

Now if only i could plumb one of these in to the zed....