Level Anything
Member
I was surprised when I heard the detail you got from yr acoustic w/ the 244 and a type I tape. Keep it up man.
Recalibrating Cassette Format Portastudios to use Type I Normal Bias Tapes
- Thread starter Illsidgus
- Start date
Thanks for the inspiration Level Anything. Much appreciated.
I've attached a frequency response plot for the Maxell UR Type 1 at the higher speed, which might be of interest. This is for 0dB record level, which is a pretty stiff test I think. Used track 1 but they are all much the same. I guess the steep decline after 16-18k is due to the dbx filtering (last point is at 20kHz, second last 18kHz) Compares quite well to some of these plots I found for studio machines at 15 and 30 ips! (response curve link)
Response Curves of Analog Recorders
I've attached a frequency response plot for the Maxell UR Type 1 at the higher speed, which might be of interest. This is for 0dB record level, which is a pretty stiff test I think. Used track 1 but they are all much the same. I guess the steep decline after 16-18k is due to the dbx filtering (last point is at 20kHz, second last 18kHz) Compares quite well to some of these plots I found for studio machines at 15 and 30 ips! (response curve link)
Response Curves of Analog Recorders
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sweetbeats
Reel deep thoughts...
You truly recorded the sweep at 0dB? Or 0VU (-10dBv)?
sweetbeats
Reel deep thoughts...
0VU does not necessarily equate to 0dB. Likely 0VU on your 244 (assuming it is calibrated to the standard for which it was designed) represents -10dBv.
Ooo! Been a long time since I was into "magnetics" but yes. You need some sort of FLUX reference. If that curve was close to max flux then as the signal level falls the HF level would rise.
This is why, (as I think I said before?) tape tests mean very little unless tied to a specific level of distortion.
Off to re-learn some stuff!
GennLab Just the first thing Google threw up. I think you need the Teac 160nVb/M cassette? Pricey but otherwise one is ******g in the wind!
First thing to do? Clean everything, de gauss and copy tape into PC!
Dave.
I'm a bit confused now! I always thought 0VU on cassette decks usually represented 200 nWb/m flux as standard and that freq response was almost always measured -20dB down from this at -20VU at 1 and 7/8 ips and -10VU at 3 and 3/4 ips. The 244 service manual says to measure freq response at -10VU. 0.3V input gives 0VU on the meters (-10dBv as you say Sweetbeats!). So I still think testing at 0VU is a pretty stiff test! The spec is + or - 3dB from 40Hz to 14kHz on type II at -10VU. Compares remarkably well with some of the studio machines in Jack Endino's tests at 0VU (250 nWb/m presumably).....
Apologies for the typo and that I did not see the 3-3/4" cassette in the link. I don't think a response at "0VU" IS a "stiff test" because IMHO it is a wrong test. Tape machines are lined up for best response at -10VU or, for normal speed cassette, -20VU. As the drive level increases HF squash occurs and so a response at 0VU is not a reflection of real world musical events.
Tape, vinyl and to some extent FM radio only works as well as it does because of the spectral balance of musical signals, i.e. we can add pre-emphasis. We must always remember that tape has a variable level/frequency mol.
Dave.
Thanks ecc83 - totally agree. I just love to test at 0VU because I usually find I run much "hotter" on the 244 than I intended on set-up and often get up to 0VU! And having done the same test on 2-track cassette decks and finding how awful they are (apart from a Sony using metal and Dolby S) I am amazed how fantastic the 244 is.
Maybe ought to add I made my own reference tape I |(thankfully!) made for 244 levels back in '82
Maybe ought to add I made my own reference tape I |(thankfully!) made for 244 levels back in '82
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Yes, good to have the headroom and low noise. Called "high fidelity" . Computers do it particularly well!
(I'll get me coat)
Dave.
skywaveTDR
Active member
It could be done but why fight the original design. The NAC tape of the 799 type are as close to the Maxell XL II that you will find today.
I have worked on these since they came out. The Type 1 tape would give a lesser output than the type 2 in reference to high frequency.
You would have to change 4 channels of record EQ and 4 channels of play eq with new 120uS values.
I have worked on these since they came out. The Type 1 tape would give a lesser output than the type 2 in reference to high frequency.
You would have to change 4 channels of record EQ and 4 channels of play eq with new 120uS values.
Level Anything
Member
He's in the UK
Yes - as Level Anything says, I'm in the UK and new type II is very difficult to get hold of! The output at high frequency is, amazingly, almost identical to the best type II and there was no need to adjust the record or replay eq. Just took about half an hour adjusting the bias on all four channels. The sound is very crisp and clean - and not a single dropout so far after quite a bit of recording - contrary to my experience with type II!
Findlay, type 2 tape is still available, albeit without cases. I have just received 10 x c60 and 10 x c90 from a company called Tapeline.
Sorry I don't know how to do links but details can be Googled. First impressions are good. I have no connection with this company other than as a satisfied customer. Oh and they're a UK company.
Sorry I don't know how to do links but details can be Googled. First impressions are good. I have no connection with this company other than as a satisfied customer. Oh and they're a UK company.
Thanks Bobreel. Have you had a chance to use the Type IIs on a 244? It seems they are using Aurex tape - I wonder if anyone knows much about this? I'm interested in buying some to try for my type II biased 244s but so happy at the moment with the re-biased Type I machine that I'm going to stick with using this - the sound is absolutely amazing.
A few more thoughts on using the 244 at high speed with the pitch control on max. I've been working this week on a song using a Type I cassette and max speed and been getting great results - terrific freq response and no dropouts. But a small problem has arisen, as alluded to maybe by Sweetbeats' comments in an earlier post. After an hour or so's use I was putting down a lead guitar part when I noticed that the speed had drifted down a little so the guitar was now out of tune with the backing track. As the pitch control was already at max there was no room left to manoeuvre. I guess in future it is best to leave just a little speed control in reserve. No noticeable w&f though so still worth using high speed I think.
Level Anything
Member
I never saw the benefit to maxing out the pitch control. I've heard people talk about doing it, especially back in the day when everyone was using 4-track cassette and seemed to have their own ways of doing things that they claimed worked the best haha. I've read about it and it doesn't add anything in terms of headroom or freq response but you already know that. I've been doing a lot of pitch shifting after the fact though. I love doing that. Have you ever recorded a guitar a slower speed and overdubbed another at normal. It'll sound like a pysch 12-string.
Thanks for the tip - I'll have to try that! It sounds like just the sound I've been after.
I did find that the max speed extended the high freq response with type I a little - by about 2-3 dB beyond 16kHz, making it as good as the very best type II. Interestingly, no benefit using max speed with type II. One other slight advantage of max speed is slightly sharper punch-ins!
I did find that the max speed extended the high freq response with type I a little - by about 2-3 dB beyond 16kHz, making it as good as the very best type II. Interestingly, no benefit using max speed with type II. One other slight advantage of max speed is slightly sharper punch-ins!
sweetbeats
Reel deep thoughts...
The increased speed should indeed shift the response curve upward in frequency, meaning increased HF response with increased tape speed (to the limits of the medium and the machine) and decreased LF response. I think the pitch control on the 244 is +/-12%? So there wo t be *much* change, but in theory there would be change.