Teac X1000R Tape Selector for Scotch/3M 250
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rob Brandt
Active Member
Hmm--I had some Scotch around but haven't seen it for years. I have the same deck as you and the manual may list the 250. Do you have the manual around for the X-1000R? If not, go over to Hi-fi engine and get one.
dhnash
Super Member
The attached article discusses how various tape parameters affect bias level requirements. It notes that the coercivity and thickness of the oxide coating on the tape are parameters that will influence this. The chart that I have also attached shows the difference in these parameters for Scotch 177 and 250 type tapes. You can see that there are differences but I am not able to tell you how significant these are with respect to bias level requirements. The simplest approach to answering your question is to check for differences in the sound of the source versus the recording (tape) while recording and do this for both the LH-I and LH-II tape selector options. The one that provides the closest match between the sound of the source and tape is probably the best choice.
Try both and decide-my guess LH-II will work better
rob Brandt
Active Member
I have to agree with the other two posters. Just try recording for a few minutes with each setting with the same exact source and which ever sounds better, go for it.
Scotch 250 was one of the first hi bias tapes offered to the pro audio industry. The X-1000R is not really set up for this tape at either position.
tape position 1 was for Maxell UD types and tape position 2 for UDXL 2 and TDK SA (the EE tape types).
The bias oscillator on the 1000 will handle it (i.e. generate enough bias current) but not the factory stock EQ settings.
If you want to see the effect, get yourself an inexpensive test tone generator. Record the tones on the 250 using first position 1 then repeat using position 2. set record level at -10db
you will find that with the 250, neither tape position will give you flat response.
if you want to use the 250 tape you either need to rebias the deck or get something like a Tascam 35 that has user adjustable bias and eq settings right on the front panel.
tape position 1 was for Maxell UD types and tape position 2 for UDXL 2 and TDK SA (the EE tape types).
The bias oscillator on the 1000 will handle it (i.e. generate enough bias current) but not the factory stock EQ settings.
If you want to see the effect, get yourself an inexpensive test tone generator. Record the tones on the 250 using first position 1 then repeat using position 2. set record level at -10db
you will find that with the 250, neither tape position will give you flat response.
if you want to use the 250 tape you either need to rebias the deck or get something like a Tascam 35 that has user adjustable bias and eq settings right on the front panel.
dhnash
Super Member
The X-1000R actually has three tape selection options, LH-I, LH-II and EE (see below). The recommended setting for Maxell UD-35 would be LH-II and for Maxell UD-XL II and TDK SA would be EE.
yes, but there is not much difference between LH1 and LH2. EE is where the bias is really turned up. Years ago I set up an X-1000R for 3M 250 tape. Used the EE position and changed the EQ parts for traditional EE record and playback EQ to obtain a flat response. It measured very flat and sounded very good.
If you look at the circuit its only a db or so of difference between LH-1 and LH-2 position, not huge.
On the X-1000R is the bias and eq are linked together. So while LH-2 lists all those tapes that are supposed to work at that setting, if you run a frequency scan you will find one that is pretty flat (usually the Maxell) and the others have either high freq roll off or a slight rise in the high freq depending on the tape.
If I still have the photos of the circuit would post them, but do not remember where I put them.
If you look at the circuit its only a db or so of difference between LH-1 and LH-2 position, not huge.
On the X-1000R is the bias and eq are linked together. So while LH-2 lists all those tapes that are supposed to work at that setting, if you run a frequency scan you will find one that is pretty flat (usually the Maxell) and the others have either high freq roll off or a slight rise in the high freq depending on the tape.
If I still have the photos of the circuit would post them, but do not remember where I put them.
dhnash
Super Member
I am aware of the design issue you mentioned regarding the interaction of the adjustments for EE and LH-II tape settings. The original design apparently allowed for optimization for only one of these two tape types because the adjustments that were the best for one type were less than optimal for the other. When I had my X-1000R serviced by Sam Palermo, who is also in the Chicago area, I had him install a modification that allowed the adjustments for these two tape types to be made separately so they did not interact with each other. This allowed him to adjust the settings for LH-II tape to be optimal for RTM LPR35 and the ones for EE tape to be optimized for tape like Maxell UD-XL II. Sam's service report noted: "The sweep of 7.5 IPS at 0 Vu with LPR35 resulted in a 24 Hz to 23.8KHz inside of plus or minus 2 dB and the EE tape indicated a 24Hz to 28.5 KHz at the same level." I believe this same issue is present in all of Teac's X-1000 and X-2000 series R2Rs.
Very cool that Sam was able to make that mod. I ran quite a few sweep tests on X1000Rs and their performance at zero db was amazing.. and only running 7.5 ips.
the X2000s had a fine bias adjustment, so gave a bit of wiggle room if you wanted to try slightly different tapes.
best
the X2000s had a fine bias adjustment, so gave a bit of wiggle room if you wanted to try slightly different tapes.
best
skywavebe
Tascam Repair
The Scotch 250 tape was a 1.5mil mastering tape not meant for the X1000R which is a consumer deck at higher speed 7.5 IPS. The 250 which I have used and set up for is most often used on 1/2 track Tascam decks that have 15 IPS on them. It is like using ATR Master and SM900 on the X1000R which really should be using LPR35, LPR90 or MDS36 tapes.
Switch setting does not make much difference at this point until you have the deck calibrated to a tape- the assembly line adjusted machine for a range of tape and it was not very specific as to which one so much slop was had there. I have had X1000R units from the factory that had a bandwidth of 9KHz and 22KHz after I adjusted it. There are mods to be done on deck for better performance besides the oil I use is way ahead of any Teac had access to and performs better giving wow and flutter figures that can be under .025% on a X1000R.
The later on and that was last year I created a speed direction mod that allows the speeds in each direction to be adjusted by 4 ten turn pots so that it is possible to get withing 2Hz of the 3KHz standard at both directions when with a stock unit they can be off as much as 1% between directions.
Switch setting does not make much difference at this point until you have the deck calibrated to a tape- the assembly line adjusted machine for a range of tape and it was not very specific as to which one so much slop was had there. I have had X1000R units from the factory that had a bandwidth of 9KHz and 22KHz after I adjusted it. There are mods to be done on deck for better performance besides the oil I use is way ahead of any Teac had access to and performs better giving wow and flutter figures that can be under .025% on a X1000R.
The later on and that was last year I created a speed direction mod that allows the speeds in each direction to be adjusted by 4 ten turn pots so that it is possible to get withing 2Hz of the 3KHz standard at both directions when with a stock unit they can be off as much as 1% between directions.