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Username: drjenney

Post Number: 25
Registered: 11-2004
Posted on Wednesday, May 25, 2005 - 5:28 am:   Edit Post

I'd be interested in whether any members have upgraded their stock Alembic electronics for better sound. Any audiophile DIY/bass players out there?
Username: davehouck

Post Number: 1804
Registered: 5-2002
Posted on Wednesday, May 25, 2005 - 6:07 am:   Edit Post

My personal opinion is that any non-Alembic change to the instrument is going to significantly lessen the resale value. That said, I don't recall seeing any non-Alembic "tweeks" of Alembic electronics to "improve" the sound. One straight forward do-it-yourself upgrade that I've seen often is the addition of a Q switch to Essence electronics; Alembic will send you the parts and instructions and it is fairly inexpensive. I do seem to recall that an Epic owner replaced his bass and treble controls with an Alembic filter and Q switch set; but I believe that was a straight forward replacement as well. And I do recall one or two instances were an owner added a stand-by switch. Most owners who want to make improvements send their instruments back to Alembic for upgrades. Of course the work is not inexpensive and there can be some considerable wait for bench time.
Username: essencetimestwo

Post Number: 95
Registered: 8-2003
Posted on Wednesday, May 25, 2005 - 10:59 am:   Edit Post

Why would you want to?
Username: sfnic

Post Number: 53
Registered: 3-2005
Posted on Thursday, May 26, 2005 - 2:11 pm:   Edit Post

I thihk that the general consensus (here, at least) is that Alembic is the top-end of any audiophile-related electronics packages that could be built into the instrument. Basically, there's no "better" to "upgrade" to.

As Dave says, there are upgrades you can have Alembic perform to many of their models, but it all comes down to upgrading your _Alembic_ to be a better _Alembic_. And, no matter how far you go, Ron and Susan and the crew can design and implement something further out.

Yes, there are other companies out there that do reasonably high-quality instrument electronics. I've worked for some of them and consulted with others. And I've seen damned near everybody's widgits at one time or another. _My_ bottom line is that Alembic has nailed it, in terms of form, fit and function. It's very hard to beat the elegant simplicity of the packaging (or those big, carved wooden things the electronics come packed in). The fit and finish is perfect, and they're pretty much optimal in terms of tone and functionality for the player. They're certainly the gold standard _I_ try to reach, in my own projects.

Sure, there are some things they don't do that might be useful to some players. Bells-and-whistle features like onboard compressors, piezo pickup elements mounted in the bridge, etc. But for the core functions most every player actually needs, this is it.

One really easy rule of thumb: many "upgrade" makers seem to think CTS potentiometers are the best around. They're not. So far as I know, Alembic is the only maker of instruments--in production quantities--that use completely sealed, military-spec Bournes, Clarostat and/or Allen Bradley potentiometers in their circuits. If a company can't be bothered to spend the extra money (or is too lazy to do the basic research into the properties of materials) for the higher-quality components, then it's not an "upgrade" no matter how fancy the feature set might be.

Of course, that's just my opinion, too.
Username: drjenney

Post Number: 30
Registered: 11-2004
Posted on Thursday, May 26, 2005 - 2:25 pm:   Edit Post


I agree that Alembic electronics are the best out there. Still, it is not heresy to suggest that it mght be possible to improve it. I wasn't thinking of additional features, but of audiophile type upgrades.

For instance, however good the pots, they are not in the same league as stepped attenuators. I'm tempted to bypass the volume pot entirely just to see what kind of tone the shorter path would produce.

I also wonder if Cardas tone arm wire would make a significant difference in the quality of the sound delivered from the pickups to the preamp.

I may take some time this summer to putter around and see.

Dr. J
Username: sfnic

Post Number: 57
Registered: 3-2005
Posted on Thursday, May 26, 2005 - 4:01 pm:   Edit Post

No, it's not heresy at all, but it's not as if this hasn't been considered before and subjected to a fair amount of analysis and research by both Alembic and independent researchers. Ron W spent months trying to find the ideal cabling for the "pickup-to-preamp" connection, and went through hundreds, if not thousands, of possible solutions. That original cabling issue is largely responsible for the current design of the entire pickup, preamp and filter architecture.

The key issue here is the difference between "improve" and "change." One can certainly _change_ the sound of an Alembic. But I'd argue that the _sound_ is a lot of what makes Alembic unique. I can build a bass guitar that can sound pretty much any way I want it to. But to get it to sound like an Alembic, I pretty much have to clone the entire electro-mechanical device, in situ.

Forinstance, I find stepped attenuators limit the flexibility of a pre-filter gain stage. You'd also alter the inter-stage impedence matching between the Alembic preamp stages. This, in turn, would affect the gain and damping factors of the filters a bit. Probably not critical, but definitely enough to alter the sound in a negative fashion (by changing the phase characteristics through the various filter poles). This isn't an "improvement," it's merely a "change."

Cardas tone wire won't have that much of an effect. The source and load impedences are different, for one thing. The pickup's inherent frequency response is another factor. The Cardas wire helps tremendously by improving the articulation above about 8KHz. Essentially, it has a capacitive reactance characteristic that improves its inertial slew rate. While this also affects the rise time response of low frequency signals, it also contributes to a very slight overshoot. Not audible in and of itself, but it becomes so when it's added into the phase response of the first preamp stage. It shines best when driving a 12AU7 directly; the tube gain curve dampens that overshoot and effectively masks it. The same signal driving a FET-front end IC, otoh, will exhibit a hair of ringing at certain harmonics (determined by the input impedence of the IC, the capacitive loading of the wire and the capoacitive reactance of the pickup's source load impedence).

The Alembic pickup doesn't have a lot of information up above 8k, so there's not a lot of help to be provided by the Cardas wire. Certainly not as much as a decent phono cartridge, anyway. Not so much because the pickup can't produce it, but because there's not a lot of fundamental signal above 6k coming off of the strings. Yes, you'd hear is _very_ slight glassiness in the overtones, but only if the _entire rig_ were set up to reproduce the top 1.5 octaves accurately. On stage? You'd never hear it. DI'd into an SSL board? Probably not. Maybe through a tweaked out Neve console, but only if the entire reference monitor signal path was totally time-aligned and phase corrected.

Bypassing the volume pot entirely won't be an improvement; merely another change. You'll change the both the preamp loading and the filter's input CR factor. Depending on which Alembic you try it on, you might even confuse the Q circuit.

Now, rebuild the instrument's entire electronic package with 1/4% tolerance components, and drive it straight into the above-mentioned reference studio setup, and you'll hear a difference. I wouldn't call it an improvement; that kind of tweak merely makes the tone more consistant from instrument to instrument. Which is irrelevant, as the differing wood mixes and changes in acoustic properties from plank to plank, coupled with comparitively inexact construction techniques (they don't measure the amount of glue used in any given joint in grams, for instance) mean that each instrument will be measurably different in overall voicing from any other. That's one reason Ron electronically sets up each instrument.

By all means experiment, though. Just keep in mind that difference between "improve" and "change." You may well (almost certainly will) discover a sound you like better. It may even be relatively close to the "standard" Alembic sound. But it will be _different_, and will contain tonal elements not initially present in the core audio generator that is an Alembic instrument.

Now, that's not necessarily a bad thing. And I guarantee that if you DO experiment along those lines, especially using an Alembic as your test bed, your understanding of ALL acoustic phenomenon will increase. You will make discoveries and you will increase your own toolkit of tricks and techniques. You WILL find sonic changes that are improvements, and that you can apply in other real-world situations.

But I'm betting it won't sound quite like an Alembic anymore.


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