Hi,
I’m a bit disappointed and upset about one thing that had been written in the past in a report about the T1.
Here’s what that person stated:
“The extrem mighty sound from the T1 results from a special coupling between the Filter and the Amp.
This alternating current coupling causes that the part of the bass is enhanced with 20 Hz.”
Additionally he tells:
“The extraordinary sound results also from having been taken over the Filter system from the big Modulars”.
I told all this to a tech who is kinda skilled with T1s and took a look into the schematics and aid immediatly that he can’t see anything about this. All seems to be a fairy tale…
Is anybody out ther who can confirm the upper stating or knows probably more about this ?
Yes. One way to get close to the sound of a Taurus 1 on a Minimoog D is to use the “feedback” trick very moderately to distort de waveform just enough. Combine with the already slightly overdriven filter and VCA sections, it results in a “beefier” bass sound..
If you really want a bass sound that will shake your teeth fillings loose (in a powerful enough PA) is to use one Sawtooth and one Square waveforms on top of that !
@Stephen
In general it sounds overwhelming, but although I know it’s a complete different construction I’m on the way, as I’ve told already here , to change my T2 into an elephant, and I’m now in the first state of thinking and asking about.
I’ve got already some ideas but I wan’t to have all not get too complex, i.ex. to interconnect an additional housing.
I even discussed some ideas to make the sound of the T1 more bigger. Don’t think to me I’m crazy.
As The alien said one importint thing tha I’ve found out are the square waves…so far…
@ the alien666
What will happen when Im going with the T1 into the Minimoog input ?
Well as for the T1 sound I want to row back a little bit…
On one side it does an enormous BOOOOOOOOOOOOOOOOOOOOOOOOOOOMMMMMMM but the sound managing in total isn’t that knocking down…
The decay release time is shorter than on the T2 and the T2 has a wider Filter opening range. And not to forget the VERY striking SYNC, and VERY important the overdrive of the the two output faders.
Now let me start from the beginning, when I got my first Prophet 08 when I played a mono sound on and had been blown away through my AKG K340 headphones. All voices on this sound had been stacked and I began to jump up and tried to compare this with the T1. The result was the P 08 sounded about 5 times more bombastic than the T1.
Besides, the T1 had been serviced extraordinary !!! two years ago, recapped copletely and all shit parts like the closed jacks had been thrown out and s.o., and I believe It’s now sounding far more better that previously.
I dicussed now since then with my tech what possibilities I might have to upgrade the T1.
I got more close to the P 08 and began to compare and recognized the the reason for its fatness, or maybe one reason are the square waves on that sound.
So then I had the idea and asked my tech if square waves or additional oscillators can be added on the T1.
Obviously square waves alone interswitchable with the sawtooths it’s no problem, but more oscillators that’s a bunch of work…the last I abandoned.
That’s all about the T1
As I’m using my T1 under Poly/Mini as a “Constallation” system, I’ve my T2 under the Chroma/ARP 2600 and want to stay independant, but want to have also BIG Taurus sound there.
What I’m appreciating so much about the T2 is its WONDEWRFUL timbre that the T1 doesn’t has. It’s only layed out mostly for basses.
The first thing I’ve planned now for the T2 upgrade is to swap the R 145 - 100kOhm into 1meg Ohm, like I’ve been told the second version of the Prodigy has.
Secondly I observed that the T2 has about 20 - 30 % less output gain than the T1 and the second step will be to enhance its output by changing the R 147 from 12 kOhm into 6,8 kOhm.
But at the end I had been warned that sound might distort at the end and wouldn’t supply what I expect…
But I’ll try, if it doesn’t work I’ll put all the old parts back.
And thirdly to have two full working square waves I’m goonna smash the two R 78 and R 79 out and install a pot for the pulsewidth alteration for oscillator two.
That’s all I know now what can be done, maybe some of you have better ideas…
I have to admit to being a little skeptical about your claim that the T1 sound is insufficient. Full disclosure here, I’ve never seen or heard one in person but I own a Taurus III, a Dotcom modular voice, a Voyager, and a Micromoog with the bass modification. The Taurus HANDS DOWN slams the bass to the floor like a champion. None of my other synths compare.
Have you compared your T1 with another T1? What are you listening to them with?
Well I’d NEVER say the T1’s sound is insufficient. I said only above that one STACKED mono sound of my Prophet 08 nearly killed me.
Why shouldn’t I try to do everything to make the sound more bombing ??? Yes, I could buy a pedal unit and play the P08 with that stacked bass sound. Now frankly, wouldn’t that be completely stupid ? That would make sense for s.o. who hasn’t got a T1.
I advise you if you’ve one day the possibility then compare your T3 with a P08…
To your next question, in the late eighties I had for a short time a second T1 as I got it very cheap. After some weeks I bartered it for my Tonus ARP 2600, also mint condition. This is one day I’ll never forget in my whole life.
That most lovely guy drove 300 km to me and put it on my table. He said that he’s a bass player and his band would often complain about his bass sound and he wanted to improve.
After he was off, tears ran down my cheeks…I still almost cannot believe this…
Well back to the comparing. I gave the second one away just only because it had a much lower serial number and had been used obviously much harder. The first that I bought for much more money belonged before to a drummer that used it only for about five times. It looks still like mint…
The only thing I observed was that one I gave away was very slightly louder at the same settings.
Now back to its sound in general. I talked yesterday to my tech and I can also approve that the Resonance of the T1 isn’t overwhelming, from the tachnical side and auditional too,the same on the Polymoog’s general Filter and the T2.
But I don’t care about this as in general as you’ve seen I want bombastic sounds.
I’ve to admit, that I still never experienced anyone through 18" subwoofers. That will be one day a great experience for me, I hope, VERY pricey gear… For 3 1/2 ks I’d buy rather an additional Poly…
For the T1 I’m going to add as I said above two additional squarewaves, that’s it…
And for the T2 I decided now dfinitively that I’ll also add two sub oscillators for each original.
The only thing that makes me very upset is that you’ll cannot detune or alter the pitch (I have to live with) but luckily alter their loudnesses after installing two additional pots.
But my tech promised me that I should take very much care of my prcelain in the wardrobe after installing
I also forwarded the report from MC to my tech and he is still doubting the dirst point. that thing with the 20Hz.
But despite he’s very interrested in and will simulate that structure on the computer for the approval. He does this also for many, many other synths and synths sections all the time…
I’m going to post his results as quick as possible.
The second point, he is considering as very likely…
The T1 filter actually has pretty good resonance, if you can’t get yours to self-oscillate then something may be out of whack.
If you ever want to hear (and feel) the T1 through 18" subwoofers, take it into the PA room at a Guitar Center. Make sure the EQ on the board is off, you will not need it.
Indeed I had this problem previously that the resonance didn’t ring at maximum but when servicing, my tech found out that one electronic part hadn’t been pushed deep enough into the PCB for final soldering.
It’s ringing now very well , but as I said like on the Poly and T2, Resonance is a bit “weak” but useful despite.
Of course I still have the Tonus. It’s babied every day and I think it’s my best sounding instrument
RUBBISH !!!
I’ve tried today the Resonance extensively with various settings on both, T1 and T2 and they aren’t weak at all.
Two reasons:
First, I din’t use them as I always have a standard setting and for the T1 I don’t like to crawl on the floor and keep that annoying cover glass upright for tweaking.
And secondly, I’m playing almost every time at night and have to work with very low settings, so this why sounds often don’t come through completely. I’ve to be VERY careful as you can hear needles drop down in the neighbour appartements.
Up to now I could only play my modern ones through the headphone but I’ve got a new mixer now and need no more going directly into the PA speakers.
But, MC, it was VERY FINE to remind me about the Resonance as I’m feeling urged now to use it more often.
Of course, the more being set, the louder the audio signal must be. And souds FINE…
I was alway too busy with all my Polys. Thank you
But another question:
Eric, and you MC, as you both have the T3, and when I’m right they have for each osc. a square-wave additionally. Can you describe how they come out in comparison to the sawtooth concerning the “bombastic”.
I’ve tried on all my synths the squares now very carefully and all sound more or less different. Depends obviously on the whole audiopath of each instrument.
On the Mini and the Tonus they sound VERY hollow, and that’s fine as it should be like, but i.ex on the CHROMA, the Polymoog and the P 08 they aren’t that hollow.
So I’ve tried different bass settings on the Mini and found out that is quite not the same as on the P08.
On the Mini I’m coming very close to my desires when mixing the the square with the sawtooth.
So at the end I’ll have to do this on the T1 (and T2) at the end too.
What are your experiences ?
I can’t help pointing out that the phase relationship between the sawtooth and square waves is mighty important for the final output. Also the fact that some synths produce a ramp up sawtooth, versus a ramp down one, will also greatly affect the sound when mixed with other waveforms.
My experience is that I can’t get a square wave out of my T3 because it doesn’t have one.
Another revelation from that same email with Bob is that the most other synths don’t produce the low end of the T1/T3 because of RC coupling between stages (VCO to VCF to VCA). The RC product is a necessary evil that forms a highpass filter that reduces bass. The -3dB frequency point or lowest frequency depends on the design of that RC product. Are other synths intentionally crippled of bass? I certainly think so when I designed the bass boost mod for the Micromoog years ago. That’s one reason why the Minimoog won’t make that low end oomph of the Taurus.
Whether a square wave sounds hollow is not dependent on RC product but is a factor is non-linear circuits. Translated, non-linearity is distortion. The most common culprits are the VCF and VCA. Even with the VCF cutoff frequency wide open, the frequency response is FAR from flat. Years ago I tried playing a CD through my wide open Micromoog VCF and it frankly sounded like sh!t. That’s a consequence of the class filter required to get high resonance for musical uses. Filter choices are a case of pick your poison, but sometimes imperfections can be a good thing. And not all filters have the same frequency response with the cutoff wide open. VCAs, notably in synths before the mid 1980s, impart their own distortion because they were not high fidelity devices and cost effective high fidelity VCAs were not yet available at the time.
MC,
I didn’t know you designed that mod. I had a friend install it on my unit and love it. Thanks very much.
Megavoice,
The only response that I can give to your question is that when I have a tinge of buyers remorse regarding whether or not the money for the T3 would have been better spent on a modular gear, those thoughts are broken away by the tremendous slam to the ground that is administered by the stampeding bull.
Now thank you guys so much for the first.
A few minutes I bought my parts and will go on discussing the last what you’ve written with my tech before installing.
I only need now the two pots (50 kOhm, linear), but with 6,35 mm shafts, as I want to put original Minimoog knobs on.
Years later after buying the T2, NEW, I observed that it hadn’t the usual small knobs. It was equipped with Minimoog knobs, strange ???
MC,
talked to my tech today and he agrees with all this.
As for the T1 he did the simulation on his PC and said, when going into the VCF with 0 dB, the VCA output shows at 30 Hz -3dB, at 20 Hz -6 dB.
So still he claims there are NO 20 dB enhancement anywhere.
Tht’s all what I can tell you about this, I hope as a non tech that I’ve reproduced everything right.
He said furtheremore, and this is ONLY an assunption !!! the special sound maybe be influenced or even created by the retrace of the sawtooth waveform. He said when looking into the schematics (???) the saw waveform is looking like an assymetrical triangle, the second decaying part of the wave is not that steep and vertical as it should be, and obviously prevails on other synths. This he said, could be a significant influence on the basic sound. And of course, on the T2 the decaying second part is different and steep and will let the T2 sound different and probably not that thick like on the T1…
This might be also a confirmation about what you’ve said about the “uncorrect” working of the parts or groups.
I can also confirm especially on the Chroma of the collapsing of the deep frequences on the deep notes like you talked about above, as my tech said its Filter cannot reach the depth of the oscillators (6 or 16 Hz, I cannot remember, sorry)
We decided now experimenting and adding on the bass slider two 10 or 15 nF caps on the upper and lower part.
We both are very interrested in what will happen after, if there’s an improvement or not.
The speaker I’m going into is a high quality active RCF monitor NX, 129 SPL
Many engineers are skeptical of simulations. Simulations are NOT measurement tools. They are only as good as the component model. The key component in the T1 sonority is the OTA and it is a highly non-linear component. The more non-linear a component is, the harder it is to model accurately. Too many circuits that worked in simulations did not function at all in the real world.
I put more integrity into an actual T1 on a hardware frequency analyzer than any simulation or software tool.
FWIW, I have spent twenty plus years in the measurement industry.
